very pleased to speak in this very nice seminar. And thank you for attending. So before giving this talk, I would like to make some publicity. So it will be from the conference, the journey arithmetic. It will be in Nancy in France. So Philippe is one of the scientific committee and I am one of the member of the organizing committee. So if you want to have some information, don't hesitate to contact me. And there is a website here and the inscription open still today. And perhaps many of you have received an email for this. And you are, everybody is welcome. So now I will begin my talk. I am very pleased to present joint work with James Menard about quartic polynomial values with a large prime factor. So I will begin with a famous conjecture in a number theory. So it says that if we take p of x, a polynomial irreducible with no fixed divisor, that means we want, doesn't want to polynomial like n square plus n plus two because this polynomial is always even. So a conjecture says that there are infinitely many integers n such that p of n is prime. So when the degree of p is equal to one, this is a consequence of directly serums on the prime in arithmetic progressions. If p is of type A times x plus B with co-prime integers A and B, the directly serums say that there are infinitely many prime p's which are congruent to B modulo A. So in the shape B plus A times x. But when the degree of p is bigger than two, it is still an open problem. But we have a nice result from Ibanez obtained in 1978. So he proved that there are infinitely many n such that n square plus one has at most two prime factors. So we have two. Actually, we can't replace two by one. But we have the meaning that it's not so far. But we are not also able to prove that there are infinitely many n such that n square plus one has exactly two prime factors. So at most also is important. And when the degree of the polynomial is big, the problem is more difficult because the sequence p of n is a spare sequence. If d is the degree of the polynomial p, then the gap between two consecutive values of p, it is quite big. It is of the size n to the d minus 1. So the problem becomes more and more difficult. And when a problem is very difficult, we try to attack a simpler one. An simpler one would be to try to find polynomial values with large prime factors. What is large does mean. So we would like to find polynomial values p of n with the prime factors say of the size n to the d. But we are very far from that. Sorry. And this is what I named the problem of chibi-chef. So we want to detect polynomial values with a large prime factor. So I will denote by p plus of n, the largest prime factors of n and p minus of n, the smallest one. And so what can we say about the large prime factors of n to plus 1? Does there exist integers n such that n square plus 1 has large prime factors? On what it is easy to do, it is possible. It is easy to find integers n less than x with such that n square plus 1 has a prime factors of this size. So it is sufficient to take prime p a little less than x. For example, less than x divided by 1,000. p is congruent to 1 mod 4. In this case, we can find some solution v such that v2 plus 1 is congruent to 0 mod p. And then if n is congruent to v mod p, then p will devise n square plus 1.  So we can do that for this polynomial n2 plus 1. We can generalize that to other polynomial. And the natural question is, can we do better? And Shibit Sheff in the manuscript's postume answered, yes. So it is the next slide. So Shibit Sheff, so what he did? So we can look at all the values taken by the polynomial x square plus 1. So we take the product and we want to detect the largest prime factors of this product. And we normalize. And then we take the limit as x tends to infinity. And he proves that this limit tends to infinity. And it was the beginning of a lot of nice results. So it was improved during the last century by several mathematicians. I won't recall all the results here. But actually, the best general result is the result obtained by Tin and Bohm. So what it is, this result, it is if we take f. This time it is f, an irreducible polynomial with degree bigger than 2. Then for x large enough, we can find integers n less than x, such that f of n has a large prime factors, means here bigger than x, time exponential, this power of log x. So alpha, the exponent alpha here must be less than 2 minus log 4. That is 0.61. So here it is the best general result. But perhaps it would be possible to obtain some better result when the degree of f is small. So here you would like to have x to the degree of f. So we are far from that. But when the degree of f is small, we can obtain here a lower bound. Can we obtain a lower bound with the power of x greater than 1? And this was done by Houli for the first time. So this is the next slide here. So for the quadratic polynomials. So we fix an integer d, which is not a square. And then Houli proved that we can find integers n less than x, such that n to the square minus d has a prime factor bigger than x to the 1.1. So for this result, we use some sieve methods. And then there was some exponential sums. That is close term sums. I won't give the definition here. And in the 80s, Dizouyei and Ivanniette obtained strong estimates from average on average close term sums. And they used some modular form theory. And so they could improve the 1.1 here by 1.2 and so on. And very recently, there was two improvements by Labortez-Chantrapeau here, and also by Merikovsky. Now we are going to the cubic case. For the cubic case, it is a little more complicated, so the results are not so good. But we can also obtain something. So Houli, in the 1978, he obtained this result. Basically, this result is a conditional result. It holds under an hypothesis for the order of magnitude as very short close term sums. And it was only in the beginning of our millennium that there was an unconditional result. It was the one of his brown. He proved that we can find a positive proportion of integers n such that n to the cube plus 2 has a prime factor bigger than x to the power strictly bigger than 1. So it is 1 plus 10 to the minus 303. So we can see that it is very small, but in fact, it is strictly bigger than 1. And we will see in the next slide that it is not so small. And Irving proved that we can replace x exponent by that. So now we are right into the quartic polynomials. And some years ago, I solved the problems for the polynomial of doga 4. It was here the 12 cyclotomic polynomial. So here there should be some parenthesis here. And so I proved that we can find integers n such that n to the 4 minus n square plus 1 has a prime factors bigger than n to this power here. So this power is very small, but I must say that it was quite a lot of work to obtain an effective power here. Even if it is very, very small, for me it wasn't easy to obtain that. So I was happy with this experiment. And this is the lab rotation. Generalize my result to polynomials of the grade 4. Irreducible, even Monique and with Galois group isomorphic to the Klein group, that is z divided by 2z times this, z divided by 2z. Then he proved that there exists an expo non-CP strictly positive. So just depending on the polynomial p showed that there is a positive proportion of integers n between x and 2x such that p often has a large prime factor. So in this theorem, the condition to be even is not very important. It is only to make the computation easier. But what is crucial here, it is the Galois group. So the Galois group is important here. And in fact, for the 12 cyclotomic polynomials, the Galois group of these polynomials is also the Klein group. So now it is time to, next slide. So I will put the theorems that I will present today, the theorems obtained with James Menard. So we take polynomial p as in the result of Regis de la Brotèche, irreducible, Monique and Quartique. And this time the Galois group can be isomorphic to the cyclic group or to the diadral group. Then we have the same conclusion. We can find a positive proportion of integers n between x and 2x, such that p often has a prime factors bigger than x to the 1 plus cp. So it remains to handle the case when the Galois group is a symmetric group on the alternate group. And in fact, if we take a random polynomial irreducible of the K4, its Galois group is in general the cyclic or alternate. So we can only handle a minority of Quartique polynomials. But it is at least a progress. And so we can handle, for example, the fifth cyclotomic polynomial. Yeah, I give also some other example. And also, sorry. And there was also a natural polynomial that we couldn't handle before. It was x to the 4 plus 2, which has a diadral Galois group. So the proof is very long. It is 80 pages. Can I ask a short question? Is the constant implied in the theorem uniform in the polynomials or no? No, it depends strongly on the polynomials. And in fact, it will be very complicated to compute. So we need to work a lot. So I have said my previous theorems for the 12 cyclotomic polynomials, I suffered, I must say, to obtain an effective constant. But perhaps it is possible to have, if we have a lot of energy, it is possible to obtain an expression of CP, of an admissible constant CP, depending on the polynomial P. But there are many algebraic things there. So you need something like that. We need to know that. What about the part greater than x, the constant implied there that's also dependent on? Yes, so the constant depends also on the polynomial. And also it would have a complicated expression. But it is possible to obtain something, but not easy. Are there other questions? No, so don't hesitate to interrupt me. Thank you. And so now I will try to give an overview of the proof. And so the first step is to try to detect polynomial values with large prime factors. And here we follow the method of P's Brown. And the first lemma is an adaptation of a result of P's Brown, we did it for the degree three. But in fact, this lemma can be also, works also for other degree polynomials. The constant will change in some parts. So we take P, a polynomial irreducible with a quartic and so. I will denote by R one root of P and N P, the norm in the extension of Q given by R one. Then I will consider a curious set. It is a set E of delta of the integers N in between capital X and two X, so that if we look at the principle ideal generated by N minus R one, and we look at the prime's ideals in the factorization of this principle ideal, and we want to compute the norm of P and we want that this norm is not bigger than X. If the products of such norm is not so small, not so small means bigger than X to the one plus delta, where delta is a strictly positive parameter. So it will be our set here. So the method of P's Brown says if we are able to find two constant delta zero, delta one strictly positive, such that the cardinality of E of delta zero, also this set here is bigger than delta one times X, then for X large enough, we will find a positive proportion of integers X with a large, such that P of N has a large prime factors. So with this born here and here. So there are some explicit things. But so, in fact, yeah, I switched to ideas quickly, but in fact, we could reformulate this lemma with prime factors of P of N because we can interpret P of N as a norm of the ideals given by N minus R one. So to look at the prime ideals here, it is quite the same to look at the prime factors of N. So in fact, we are detecting P of N with a large divisor formed by prime factors of size less than X. And so what we will see soon that it is nice to switch to two ideals, but the idea behind this lemma is that in general, if we take an integer N, then P of N has at most three prime factors bigger than four times X because N, P is of degree four. So P of N is less than X to the fourth time constant. So we can't have four prime factors like that. And when N is in the set delta zero, then P of N has at least a large divisor formed by small powers. And so P of N has at most two prime factors in this thing. So we play with these things and with that we can approve the lemma one. But it is, the idea in lemma one is that. So now by lemma one, we need to have a set of integers N with such that N minus R1 belongs to some nice ideals J. So here I won't be very precise, but I will consider a set of ideals of the integering associated to R1. I consider a set of principal ideals satisfying many, many conditions that I won't quote in the slides. But what I will impose here is that we want that the largest prime factors of the norm less than X. And we want that these things, this inequality, the norm is not so small. Why I do that? So sorry, it is here because of this condition here. So we want P plus or less than X and we want this inequality here. This is why I made this condition here and this condition here. With these two conditions, A1 will be a subset of E delta zero. So we will, it will be sufficient to have a lower bound of that. Now I have, it will be to make this thing easier. And I will add this condition here in order to have this lower bound here because if all the prime factors of the norm of J is like that, then an integer N will be, so N minus R1, the norm will have a finite, sorry, I tried to reformulate. With this condition here, we can deduce that N minus R1 will belongs in at most two to the four times B ideal G like that. So we can have this lower bound below. Sorry, I'm not very clear here. My, and so now we have, we need to study the integers N between X and 2X such that N minus R1 belongs to an ideal G, J, where J is an ideal like that. So it is a step. And so now we need to understand this condition. How can we understand that? It is the next slide. So now we would like to understand this because here it is integer, it is the root of a polynomial and here it is an ideal in an integral ways. So can we switch to only with integers? So I will take J, the principal ideal generated by alpha. So I will, and I can choose alpha so that with A0, A1, A2, A3 and integers. And I will work with, I propose to work with a particular case, the case X square plus two. So that we will have the root to the fourth would be equal to minus two. And the starting ideas to study this congruence is very simple. It is to remark that alpha belong to J, R1 alpha also belong to J and the square of R1 alpha belong to J. It is only this trivial observation. So alpha belongs to J means that A0 plus A1 R1 plus A2 times the square of R1 plus A3 like that is congruent to zero modulo J. So I put the minus A0 here. And then I multiply this equality by R1. So A0 become A0 R1 and so on. And here, A3 times the cube of R1 multiplied by R1, it will be A3 times R1 to the fourth. So it will be minus two times A3. And so we will have a second equation here. We do the same by multiplying by R1 to the square and we obtain here three equation where the unknown R1 square on the cube. And so we can formulate here with the system. And now we can use the Kramer formula. And by the Kramer formula, we will see that we can have an equation, R1 times the determinant here is congruent to the determinant here that is this determinant by replacing the first column by this one modulo J. And in fact, we can switch by some algebraic consideration. We can replace the J by the norm of J. And in the next slide, we will have a general lemma. So it is here. So I come back to this lemma. So now we have a general polynomial. We take again alpha. And sorry, I wanted to see that this determinant, sorry, I come back to the previous slide. This determinant are special determinant. In fact, this determinant are co-factors of the matrix of multiplication by alpha in the basis one R1, the square of R1, the cube of R1. And we can prove the same for every polynomials. And so I will introduce some notation. So I take G principally, an ideal generated by alpha. And M alpha be the matrix of the multiplication by alpha in the basis one R1, the square of R1, the cube. And I will denote by capital B, IG, the co-factor matrix. And the lemma too says that is this co-factor here, is co-prime to the norm of alpha, then we can have a sort of parent matrixation of this congruence. We have the N minus R1 belongs to the ideal generated by alpha if and only if N is congruent to these things modulo NP alpha. So here it is another co-factor and the bar here means the inverse. So now we have a congruence with only integers. And when we have that, we can detect the N between X and two X satisfying this congruence by exponential sense. And so we arrive to these things. So we need to evaluate. So I reuse the notation E of T is equal to exponential two IPT. And then we need to have non-trivial bond of this exponential, don't? So we have an exponential sums with four variables, the coordinates of alpha A0, A1, A2, A3 are in sort of domain D, so I won't describe it, but we can do such that we can control the size of the AE. And here we have a polynomial, three polynomials depending on A0, A1, A2, A3. The problem is that the denominator here NP of alpha depends on A0, A1, A2, A3. So we would like to eliminate one variable, for example, A0. So what we want to do, so I'm perhaps going too fast, it is to make an approximation of this rational fraction by another one where in the denominator here, we will suppress the A0. It is the next slide. So to do that, we can use resultant. So I will write, so it is not very important here, I'll write the coefficient of P of X and I will define R0, the resultant, it would be natural to take the resultant between B14 on the norm of alpha, but in fact, it is more efficient to take a resultant between two cofactors, B13 and B14. And we take the resultants relative to A0. And then we can compute, in fact, by using Sage, for example. And we can see that R0 have this nice factorization property where Q3 is a quadratic form with an explicit value here. And Q, it would be too long to write it on the slide, but it is a form or more genius in degree six. And then, sorry, I hope it's okay.  And so then doing some computation and with this sum, we have our approximation. So I recall the notation E of T, it is exponential two I P T. And then our previous term here, it is close to this part here, plus I have forgotten in H here, but it's not important, H times this rational fraction. This rational fraction is not very important. What we can say, its size is quite small and we can remove this part by partial summation. So we can forget it. And so this lemma means that this exponential, this exponential term is very close to these things. It's okay. Perhaps by usually in gift work, I'm going too fast, I'm sorry. So I will, the next slide summarize in which step we are, what we need to do now. We need to be able for many A1, A2, A3 given, for many of them, we need to be able to bond non-triviality the sum of types, the sum of A0 in an interval like that. Q, it depends not, so Q doesn't depends of A0, Q depends only of A1, A2, A3. And this polynomial U on B14 depends on A0, A1, A3. A trivial bond of these sums, it is the size, the length of the interval, it is B. And usually when we meet such sums in analytics number theory, we hope to be able to use the very bonds coming from arithmetic geometry. And the real bond says that we can bond that, we can, it is a capital O of the square root of the denominator. But here it is not, it is too big because you recall that Q is a form of degree six. So the size of Q is B to the six, which is, if we take the square root, it will be B to the cube and it will be too big comparatively to the trivial bond. So we need to bond that B to a power strictly less than one, voilà. And Uli in the cubic case, I have a closed amount sum, so it would be polynomials of degree one here and some nursing here and so on. And for the, but the interval here was very short and the hypothesis that I mentioned in the beginning of my talk, it was for this step. And his bonds solve these things because he observes that if Q has a good shape, we can obtain no non-trivial bond. So it is the next slide, it is a result of his bond on short exponential sums. So we take two polynomials, F and G of degree D and another things it is a denominator Q, which we, Q is square free and also it has localized divisor. So we can factorize Q as Q zero times Q one times Q four. And so there are all the technical condition here that I want to describe and what he proved. So we consider the sum here on the end in this interval, such that G of N is co-prime to Q because here it is the inverse of G of N modulo Q. And the bond, so the bond here, it is less than the module of these sums is less than the trivial things. So the length of the interval times a very small power of Q on here in the bracket is what we can win. So here we win something if Q zero is not too small, if Q zero is bigger than that. And here are good news. We win something, oh, sorry. We win some, we win something here. If here it is less than a negative power of B. So we have some place Q zero must be less than the square of B. It is a very good. And here also what it is very good. We win something if the Q i is less, are a little less than the length of the interval, B to the one minus epsilon zero. And what it is also nice is that the integer K can be as large as we want. So we can have K is equal to 10 and also one. So if we are, so we hope to be, we would like to use this bond. To use this bond, we need to find many integers A1, A2, and 3 in a small box such that the denominator Q, A1, A2, A3 is square free and also have a nice factorization. Q is equal to Q zero with Q zero quite big of the size B square and the Q1, Q2, Q4 are close to B, B to the one minus something. But in fact, it is not always easy to do that. And so we need to understand the form Q because Q is a degree six. So what is the form Q? It is the next slide. The form Q, the problem of the, to understand the form Q was solved by laboratory and master. So they obtain a very general result for the shape of Q. So you remember that Q times another quadratic form it was the resultant of two cofactors of a matrix by some multiplication. And so they prove that they obtain a precise description of the form Q. So if R1, R2, R3, and R4 are the root of the polynomial P then we can define these things. I zero, so A, it is A zero plus A one time error and so on. On Q, the absolute value of Q what it is, it is these things, it is the different product I of evaluate at the root R A minus A evaluated at R J divided by error. It is difficult for me to pronounce the difference of the roots. And we take all the possible product, the A on J between one and four on this time. And so there is no repetition. And so here we see the importance of the Galois group because the Galois group of P has an influence of Q on Q. When the Galois group of P is the alternate groups of on the symmetry groups, this form is irreducible. And we are not able actually to find many A1, A2, A3 such that Q has a nice factorization. In my work for the 12 cyclotomic polynomials and the work of Regis de la Bretagne, the Galois group was a client group. And in this case, Q is a product of three quadratic forms, Q1, Q2, Q3. So we have naturally divisor. We can split naturally Q in divisor. And then by some conting with some lattice arguments, we can estimate, so this is the first technical slice, not the first. So we can evaluate the number of A1, A2, A3 in given interval such that the Q1 evaluated A1, A2, A3 and also have a nice divisor M1, M2, M3. And so we can control, we can put some condition on M1, M2, M3. So we can say that M1 is a product of two big prime factors. And what it is nice here is that we can take here the size of M1, M2, M3, the products can be big. As big as a cube of B minus epsilon. And so with these things, we can find many integrals A1, A2, A3 such that Q has a nice factorization. But this works only for the client group. For the D'Edral, when the Galois group is D'Edral on C-click, the situation is not so good, but it is not so bad. We don't have three quadratic form, but we have a form of degree four and a form of degree two. So the previous method doesn't work, but the form of degree four is a very special. So when the Galois group is C-click of D'Edral, we can order the root of P if I name it A1, A2, A3, A4, such that this A1 times R2 plus R3 times R4 is rational. So here is what we name the root of some cubic circulant associated to the polynomial speed. And one of the roots in our case is rational. And what we observe is that the form Q1 is in fact an incomplete norm forms. This is a norm of this element, A1 plus A2 times this plus A3 times this in the extension generated by R1 plus R3. And this is an extension of degree four. And since it is a norm, there is some multiplicative structures behind that. And so we can do something. And there have been in this millennium since the beginning of the 2000 years, very nice results of primes represented by an incomplete norms on other forms. So I take the opportunity of my talk to give some history of that. And so in Friedlander and Ivaniac, it gave the first very spectacular results on this field. They proved, they obtained an asymptotic formula for the primes represented by the form A form plus B square. It is very impressive because there are very few integers of this type. And if we would like to bond the number of n less than x such that n is of the type A4 plus B square, there is at most a capital times x to the three-quarter in such integers. And so there are some generalization by Isbron and Lee and also by Merikowski. And another very impressive results in analytic number theory, it was a result obtained by Isbron. He obtained an asymptotic formula for the primes of the form A3 plus two B3. So here again, it is a very spare sequence. So there are at most a capital O of x to the two divided by three integers less than x of this type. So we can actually, you can find forms like that. And then it is natural to try to obtain such result in more variables for incomplete norms with more variables. And it is what achieved by James Menard recently. And I will present here his result. So it is, we take now F and irreducible polynomials with integer coefficient, theta root of F, and the K is a field generated by theta and N the norm. And so small k will be the number of excluded variables. And so what he looked, we want to count the number of A1, A to the N minus K such that the norm of A1 plus A2 times theta plus A3 times theta square and so on. But we stop at N minus K, we want that this norm is prime. And he obtained an asymptotic formula with the expected things. And this formula is in the case when if K is a number of excluded variables, the degree of F must be bigger than 4K. In fact, he has also another result with not asymptotic things, but with a lower bond of the good order of magnitude. Here we can almost replace K by three, not exactly three, it is 22 divided by seven, but it is not so far from three. And if we replace four by 22 by seven, we have a lower bond on here. And for us, we are, we remember our form Q1 is of degree one or four and we have one excluded variables. And so for K is equal to one, we can take N bigger than four. So it is good for us. And so the idea is was to, we can hope to adapt some ideas of the proof of minor to our problem. So you remember, we need to find a Q1 with localized divisor on Q2 also. I come back, perhaps you have forgotten because here Q, it is Q1 of degree four and Q2 of degree four. Hop. So sorry, it is here. And it was, we did that. So in the proof of a manner, there was some harm and sieve, combinatoria is very complicated sieve method. So it is a very long paper, more than 100 pages, 122. So it is very, there are many things in it. And in the analytic number theory, we meet the type one sum. It was a sum that we meet for the client group and the type two sums. And our problem is quite a type two sums problems because we want to detect values with a very, very large divisor. So two, so larger than the natural barrier. And so what we proved. So now it will be, we can, what we did. We can find integers a1, a2, a3 in some boxes such that Q1 is a multipliers of product of primes. Q2 is a multipliers of small primes where the size of the primes here is quite big, bigger than the natural limit be the cube of b. In fact, the size here is very close to b to z4. So I will soon finish. So I will do a more complicated formulation. Sorry, there will be a lot of notation. So, and in fact, our result may be likely generalized to many forms, but we wanted to obtain a result sufficient for our problem. But I think it is possible to have a more general result. So we take a quartic extension of Q. I denote by all its integral ring. And I take a basis, nu1, nu2, nu3, nu4, z basis of, okay, such that nu1 is equal to one and k is generated by nu2 and f is a quadratic form Q2. And so we suppose that if p is congruent to one modulo some integer d depending on f, f split very well modulo p in two linear forms. And so we are considering the a1, a2, a3 in some box, so on some size x such that d divides Q1, our Q1 it is this norm in complete norm form and p divides Q2 here, Q2 is the quadratic polynomial f. So we want to have this and in this term we add some congruence condition of the a1, a2, a3. And I don't know, I hope that you can see here that our result is, so I don't give all the hypothesis but we have some estimate like that. And what it is the main difference with the work of James Menard is that this nu here because we can have an average condition of the p0 when p0 is bigger than the power of x. So here's the congruence here. We can only handle when the modulus m is less than the power of log x. But for the form Q2, we need to be under congruence modulus bigger than the power of x. It was the main difference with the work of James. And I will give briefly the ingredient of proof. So as we said, we switch to ideals in UK to have some multiplicative things. And then we use some sieve weights. So I will go here very quickly. Some dispersion methods. It is tool from analytic number theory. And then we meet some a lot of lattices conducting arguments. And here it was necessary to have a form here and not an individual congruence. So, and it is finished. Thank you very much. Thank you.


What's the most you spent on a pair of shoes and what was it? So, it was like $500 because I'm new to collect the shoes and it was these. Oh dope. Yeah, these five. Yeah, you gotta stay fresh. I like it. What is the most you spent on a pair of shoes? Shoot, I gotta go, uh, I spent like $400 on these ones, the Jordan 4s. I spent about a band on some Off-White ones, the UNCs. That's probably the most I've ever spent. Yeah, yeah, yeah.


Rwy'n gweld i'n mynd i'w gwaith, yna'r ysgolwyddiad mwych. A'r ysgolwyddiad yn y gwaith ffyrdd, rydych chi'n ddangos ei chyddiad o'r bach, gallwch yn ddifent y gwaith y gyrdd yma fydd wedi gwneud. Ond rydyn ni'n elio'n ddifent i'r ysgolwyddiad i'r ysgolwyddiad ar y gymryd. Rydyn ni'n ymgyrch i'r gwaith, ydw i'n gweithio. Ddweud. Rydyn ni'n gweithio. Ychydig ar ôl yn ffrwng. Cymru o'r ffordd ar y cyd-diol yn ffwrdd. I'r ffordd ychydig, rydym yn ymgyrch am y gyfyrdd. Roeddwn i'n rhaid i gael adnodd y cyfgareddau工作au a'r holl ac o'r holl o'r holl gynnal arall eich ganodd, a'r holl i'r holl i'r holl i'r holl i'r holl i'r holl, Menerント premium om ma dressing is not so good but bare with me. I go around the world giving workshops and talks and I love washing workshops and talks. I give little ones and big ones. I teach soldering and I like teaching soldering. When people come together and solder everyone just seems to be happy. I've been like I look happy, right? Iel y cydweithio ar y dyfodol yn y hwyl hwnnw, yn gweithio ar y ddweud i'r ddweud. Mae'n gwneud hynny o'r holl ddweud o'r cyfnodd, dwi'n ddweud yn ymdweud i'r cyfrifio. Roeddwn i'r cwmwch o'r ddweud yma. Rydym yn ddweud i ddweudio'r ddweud. Rwy'n ddweudio'r ddweud i ddweudio'r ddweud. Mae'r ddweud i ddweudio'r ddweud. Dwi'r cyfreidio'r troi amdano. Mae'r iweithio'r cyfreidio eitem ei hwn cyfyniadau. Mae'r cwennu cyfyniadau cyfnodol, ac mae'r gynghoru unihonau 600 o'r hwnnw i gyfynodol arnyn noblegol am y cyfrath. Mae'r holl hwnnw hwyl'r cyfrathau a dweud yw hwnnw. Mae hi'w hwnnw i'ch gyfrathau a dwy wedi amgueddfa wedi ffodol. Mae gweithio'r cyfrathau o'r holl hyn yn ddorol. Dyna'r gyda'r sgwrs sydd wedi'i gweinio'r kit. Mae'n gweinio'r kitau yng Nghymddur RGU Mwysig Synthesizer, ac mae wedi'i gweinio'r kitau mewn i'r llun o'r cyntaf. Mae'r prim ymddur iddyn nhw yma, oherwydd y gweinio'r kitau, Ond mae'r cwyrd yn gorfod yn y bwysig, mae'r gwybod sydd yn gweinio ar y cwyrnod, a'r cyllid yma yn unrhywun o'r partyn o'r meddwl. Mae'n gweinio'r un o'r bwysig, a phobl o dyfod iawn yn y ddweudio ar y cwrnod, yn y ddweudio ar y ddweudio, a'r hwn o'r ddweudio ar y ddweudio amweld, bydd y ddweudio ar gweithio a gweithio ar y ddweudio. Mae hwn o'r ddweudio yw gweithio, ac mae oedd nhw'n ddweudio ar ardu wrth gwrs mae'n ddweudio ar ardu wedi ddweudio. Mae'r ffordd o bwrth gweithio yn ddweudio. A yna, ydw i'n dweudio ar y ddweudio ar y dyfodol the controlling program, and that's the hard part. And I'll talk about some of that. It's just some pictures of workshops I've been doing over the last couple of years with the earlier version. It's totally mature now though. But it's still a work in progress, I'm still making it a lot better along with the help of my friend Bill Alessi, who is a brilliant firmware engineer. My motivation for doing R.D. Touch was to make something that makes sound. You can learn to solder with it, you put it together, and it just works and it makes a cool synthesizer because I didn't really see many kits that make really cool sound and music and noise and I like sound and music and noise. Noise is great. So when you make this, it just works. And it's easy to debug if it doesn't because it's a simple kit as far as the hardware goes and if you want to, you can learn a little bit about Arduino or if you already know about Arduino, then you can reprogram it to use any of my synthesizers and reprogram it to some way cool variety of different music, sound and noise. And if you want to learn even more, then you can read the documentation and follow some examples and learn to make your own synthesizers. And if you want to learn even more, then you can read my documentation, which I've been proving all the time to learn digital signal processing, which is a fancy phrase for how to manipulate things with a computer to do cool things in the world. So here's just one demo video. This is the one it comes with. It's called THICC. It's for sawtooth waves and you can manipulate it and make a variety of different sounds with portamento gliding between notes and a couple of sounds otherwise. It's kind of cool. This is what happens when you hear when you build the Ardu touch and it just works. It's fun. But just to put this in some context, not that my project matches up to these other peoples, but I've been fascinated with electronic music all my life and people have been playing with electronic music for a long, long time. One of the earlier people who's one of my musical heroes is Theramin. He made the thing which is best known for really bad Hollywood sci-fi movies or the original season, first season of Star Trek with a human-like voice going, ooh, ooh, ooh, ooh. That's a Theramin. And when I went to university, I turned out that my advisor, one of my advisors had been playing with music synthesis since he was a kid and the black and white photo is his PhD thesis. It's a whole bunch of oscillators that mix together to make lots of super-interesting noises. And I was just at the University of Illinois as hacker in residence earlier this year and met up with him and there he is looking a bit older than when I remember him as an advisor, but he's still doing great. And here he's playing an emulator of his original synthesizer that was from 1964. As a little kid, I was fascinated with Switched On Bach by then Walter, now Wendy Carlos, and like wouldn't it be cool to have a wall of things like that that you could plug things into and whatever? So Switched On Bach was one of my favorite records as a kid and when it started becoming part of all rock and roll music, I had another musical hero with Keith Emerson. He could even play this synthesizer upside down on a stage, kind of acrobatics, but it was fun. And later in the 70s was the first one you could actually buy for affordable. This was like 80 bucks in the U.S. and it made cheesy sounds, but you could buy it and it worked. And later there was one that I got used that made all sorts of crazy noises, dx7. Oh, that captions wrong. That's a dx7 by Yamaha. And I've been making synthesizers since I was in middle school, simple ones, and then through high school getting more and more complex and it turned into my masters thesis to have a digital synthesizer. And that cost a lot of money, but our lab had a million dollars worth of microcontrollers that were donated by Intel, which helped me in my music quite a bit. Now it's much easier to do things and the RG Touch Music synthesizer is just 30 bucks and U.S. and it's really easy to play with.  Music synthesis has two major kinds of approaches. There's analog and there's digital. And analog is, like in the real world, everything's analog. Everything's smooth. Everything's connected to everything else. There aren't major jumps unless you're talking about quantum and really, really smaller, really, really big things, much bigger than our day-to-day lives or much smaller, but in our real world it's all analog. And doing digital means you've got to muck with the analog world, get it into a digital form and then muck with it some more interesting things happen and then turn it back into analog. And there's a lot available nowadays. These people, teenage engineering, make lots of interesting little modules that do fantastic things and they're super inexpensive and there's also, of course, fantastic performing musical instruments that are still analog and digital. Analog I still think is the greatest, but you can do so much with digital on your own that's hard to do with analog on your own.  And they all have different sounds and they're all interesting and if you mix them together in different combinations in different pitches and then muck with it in certain ways with filters, you can get amazing sounds and great noise. So with digital, you can try to just emulate an analog synthesizer, like the old mini-mogue, which actually had a roommate in university, you had a mini-mogue and we made lots of sounds and annoyed the hell of our neighbors, which is always a fun thing to do. But with digital, you can emulate an analog synthesizer and it'll never be quite as good, but you can get quite, quite good. But with digital, you've got to take whatever's in the real world, break it up into little bits because that's what computers use, is bits, bytes, words, and then mess with it in certain ways, either through calculations or real time with knobs and buttons and you can use all sorts of interesting math to muck with it as well and then put it back together again to put it out into our world where you can hear music, sound and noise. And to do that digital signal processing really, really helps, that fancy phrase. But it's really not that difficult to be able to play with this stuff and I'll talk about that. There's various forms of digital synthesis and my Argy Touch music synthesizer makes use of all of these. The easiest one to talk about is coming later, but additive is a really interesting way to make sounds and my advisor from the University of Illinois back in 64 did additive synthesis to create all the sounds he makes with his gear. It's just a bunch of sine waves, some dead French mathematician named Fourier figured this out if you have a bunch of sine waves at different volume amplitude and different frequencies and add them together, you can add them together in a form you want. And here's just a few pictures which show how to add a few sine waves together to get a square wave. If you do 13 of them it's pretty much indistinguishable from a square wave. Here we just have four of them showing how to get really close to a square wave. We can also have FM. FM is a sine wave, a frequency that, the frequency is changing over time and it's a sine of a sine function and this is what the DX7 used very effectively in the first very popular FM synthesizer and this makes just totally nutty sounds but it can make really beautiful sounds as well like a bell or a trumpet that was very difficult to do earlier with analog synthesizers. But to get into this form wavetable, you can think about a tape loop. So it's a tape loop, it's kind of like with a vinyl record. Old vinyl records, if you turn the motor off and you can spin it with your finger you can make it go slow or fast and people who scratch make use of this they also go backwards. The sound is recorded in the grooves of the record. A tape loop, though, the sound is recorded in a continuous loop of sound and you can make it go faster, you can make it go slower with a motor controller and if you have a record head you can put new sounds into it and it just repeats and repeats and a wavetable is kind of like that except the sound is put into a form that a computer can understand, digitized and then we can play it back from memory or slower but we can also do lots and lots of things that are more difficult to do with a tape loop like do mathematical formulas on it and all sorts of interesting filtering techniques and muck with it in lots of ways. For digital we start off usually with the analog world and then convert that into a form computers understand. So we can take just a simple sine wave, there's one cycle of a sine wave and to make it into a form that a computer can understand and then slice it up into chunks. This is called sampling that's the fancy digital signal processing word sampling so here I cut up a sine wave into 10 slices and each slice has a value we can put a dot where it crosses the waveform and each of those dots has a value we can put the values on like this and then record those values in a table it can be a piece of paper that's not so useful but if it's memory now we have it in a computer where we can use it and muck with it and do all sorts of interesting things with that so this is a sampled sine waves with 10 samples usually we use much more and I'll show you why soon so these samples are stored in memory it can be a simple one waveform but it can also be a very complex waveform that's several seconds or even longer like this is sort of a simplified version of a piano-like sound part of a piano-like sound and those values are stored in memory in order to get from a waveform in our real world the analog world into memory that process is called analog to digital conversion and here's a little diagram of that we can take the waveform put it through an analog to digital converter that's just a black box and then outcomes values that are stored in memory people in the field call this A slash D A to D conversion but how do you do that? what is that black box? well that black box can be a chip and see how all that works would take more than I can go over in this talk but it's not all that bad so by the chip you can just set it up according to the schematic in the data sheet and it just works but nowadays even inexpensive microcontrollers have them built in and they're basically free and once you have it you probably want to play it back you won't want to play it back exactly as it is or you might want to muck with it first and then play it back but in order to do that you do the opposite and that's digital to analog conversion so it's just the same thing but reversed we have a different black box now called digital to analog converter and outcomes the waveform ideally and then from there you can put it into an amplifier and rock and roll so that's the idea so D slash A is the fancy professional way of saying it but that's really what it is and so what's in this black box well again you can have a chip which is really expensive actually to get a good one or you can use PWM and I'll say what PWM actually means after I go through a few more slides so you can understand that PWM works with basically square waves so a square wave though is on, off, on, off, on, off and it's half on, half time it's on, half off same time on, off, on, off, on, off and so with a square wave it's basically half the amount of energy of if it's on all the time because it's off half the time as well rather than have just square where it's 50% on, 50% off we can have different ratios of on, off time like a pulse wave and analog synthesizers make use of pulse waves just to make interesting sounds as well but here's one that's 25% on and 75% off and that ratio is called a duty cycle so 25% that means there's 25% of the energy coming out compared to just on all the time and we can have various ratios it doesn't have to be even numbers either it can be a fixed point down to as many decimal places as you want it can be on for 37.4644 whatever it can be any value and you can vary the amount of energy coming out by varying the width of these pulses and when you vary the width when you change something over time in electronics that's called modulating it and what we're modulating here changing over time is the width of the pulse wave so pulse width modulation PWM and this is the way that you can make all sorts of amazingly beautiful and nasty noises out of a microcontroller and it's free because all microcontrollers have output pins and many of them have timers which are designed for PWM make it easy for you so the same diagram before except the black box is labeled PWM so we have values in memory we feed the first value into our D to A converter digital to analog converter outcomes the first little bit of our waveform then feed it the next memory location outcomes the next part and you go through the whole table byte by byte or word by word waveform and you can put an amplifier and rock and roll and it's totally cool you can make really cool, nasty and wonderful and beautiful sound music and noise so that's the theory in practice however there's a bunch of gotchas so this is what we want we want a table full of values that's our waveform in digital computer form feed it through our black box digital to analog converter and out comes a perfect waveform in this case a sine wave in actuality however we get this because computers don't have all the values in between we only have samples each memory location is just one point of the waveform and that value stays there until you put the next point in and the next point in the next point and this sounds nasty that might be a good thing but if you don't want that and you do the wonderful sine wave you're out of luck so in order to fix that according to theory all we need is a perfect low pass filter a low pass filter lets low pitches through but not high a perfect one you pick a frequency everything below comes out perfect everything above doesn't come out at all and if you have a perfect one of those then you get a perfect sine wave out but of course perfect doesn't exist in our real world but we can use a really cheap one so perfect doesn't exist but we can use a really cheap low pass filter which on my RGTouch is just one capacitor and one resistor for each channel and I've got two channels at stereo and from this if you put it through my cheap low pass filter you don't get a perfect sine wave out you get this kind of messy-ish sine wave out and that actually sounds okay-ish to fix that what we do is we have more than 10 samples for a waveform we have like 256 and if you have 256 with this cheap one you get pretty much a perfect sine wave out not quite, our ear is more sensitive than our eyes it looks like a perfect sine wave but it sounds a little bit scratchy but I pulled some other tricks and some waveforms that I wanted to be really smooth I have way more values than 256 it also helps if the values are more than 8 bits if the values are 16 bit words or even 32 bit words rather than 8 bit bytes then the values are much more accurate so that's really all there is to it to get from the analog world to computer ease and then from computer ease into the analog back to the analog world where we can make music but that's just showing how to get the waveform what we really want to do is change the pitch a lot because we're playing a keyboard or playing with a breath controller or all sorts of things or just with knobs we want to get all sorts of frequencies lots of different pitches to make crazy sounds in music and all sorts of things so how do you get different pitches well in order to explain this I'm afraid I've got to do a little bit of maths hope that's okay sorry about that but it's cool maths so if we have 256 memory locations to describe a waveform and we send one value out at a time to the digital to analog converter and out comes our waveform what is the frequency of it well if we send one every second then we can have the complete waveform in 256 seconds that is way too slow for human hearing for human hearing we've got to have a 20th of a second minimum to do a waveform and that's a really really low note and we want all the way up to a 20 thousandth of a second so one hurts that's the way of saying one per second isn't fast enough and this again is called the sample rate the rate at which we play the memory locations through our D to A converter to get the sound out so let's instead of one second in the argy touch I use 15,000 oh it went over that we use 15,000 samples per second 15 kilohertz sample rate and when we do that we can get much more interesting things but still it's rather limited if we just do the 256 samples in our memory and play them one at a time 15,000th of a second later we get 15,000 divided by 256 memory location samples and we get 58.6 hertz 58.6 cycles per second that is basically the frequency we get out and that is a pitch near a sharp the lowest a sharp on the keyboard that's not a very useful pitch especially if it's the only pitch we can make no one else can play with us unless they go off tune on a violin or a slide flute so what we want to do is get any pitch we want if you have a keyboard you want to get every note on the keyboard if you have a knob you want to get every sound you can hear in range of human hearing 20 times a second to 20,000 times a second so we can do that in two ways one way is really hard and that's like a tape loop change the speed of the tape going around or change the rate of all of the memory locations feeding them in the D to A converter faster or slower we can only get 58.6 hertz max so that's not really a good way to do it and slowing it down is complicated in code so the one way to do it is to skip memory locations and if we skip them then we can get a faster sounding we can get a higher sounding pitch and skipping them is in quotes because what we're really going to call that is interpolating and let me show you how that works so let's say we want an A and in music A 440 is defined as 440.000 times a second hertz that's the definition of A, middle A on a keyboard in all instruments so if we want to get 440 hertz and we've got samples coming out every 15 thousandth of a second we divide 440 into that and we get 34.09 steps so that means we skip 34.09 memory locations every time we do an output of a sample how do you get a 0.09 memory location well you can't you have locations 0, 1, 2, 3 only integers you can't go to location one and a half that doesn't exist or 34.09 that doesn't exist but we can interpolate between location 34 and location 35 so we'll skip 34.09 every sample and I have some pictures to show how that works so we start off with just the first one location 0 and whatever values in there goes into our D to A converter and that's the first slice of our waveform then we go to location 34.09 we can't do that but we can go to weighted value between location 34 and 35 it'll be really close to the value in 34 and then we add 34.09 to that to get 68.18 and then we have another weighted value between 68 and 69 and then we get to the next one 102.27 etc etc and then in the 7th value we get 238.68 it's still in our table but the next one it will go to the memory locations that we have so we wrap around to the top so this would have been 272.72 but we wrap around by subtracting 256 from it and now we're back in our table and now we have locations 16.72 a weighted value between 16 and 17 and we just keep going around and around and around and we do that at that rate and out comes a perfect waveform through our cheap low pass filter at 440 Hz A middle A on the keyboard and it can be the sound of a normal piano, it can be a sound of a sine wave, a square wave, a violin like sound, a trumpet sound, whatever it just depends what's stored in the memory and that's really all there is to it to do it conceptually maybe you didn't follow all that absolutely perfect but hopefully we have a feel that I went through and to code that is kind of complicated but I already did it and if you want to hack on my code feel free it's totally open source but I made it really easy by putting all that low level stuff in a file and having all of these functions in an Arduino library so that no one really has to do that unless they want to hack on my code and feel free and if you come up with something cool let me know because I'll share it with other people then but my Argy Touch makes it really easy to do all these things and that's part of the idea to make it easy on the highest level but make it so that it's totally hackable so people can do all sorts of more interesting things that I've come up with so the Argy Touch library makes it really easy to create oscillators and those are the various waveforms they can be the simple ones like sine waves square wave triangle etc we have a whole bunch of really interesting very complex beautiful and nasty noisy waveforms as well but if it's just an oscillator even if it's a beautiful or nasty whatever kind of waveform it's kind of boring because it's not changing over time any actual instrument analog instrument mechanical instrument it changes over time a great deal and it sounds much more interesting than just on with the static sound and then off so for doing that we have dynamics and I'll have some explanation of dynamics in a bit but that is what makes the sound super interesting the oscillators like I said can be the simple waveforms or more complicated ones and dynamics can be some of these and other things ADSR is what happens when you play a note like on a piano keyboard when you press the key it goes and then it decay that's the attack and then it decays quickly and then as long as you're pushing the button it sustains and slowly goes down and then when you let go of the button it goes down to zero rather rapidly and that's one waveform for attack decay sustained release and this is called an envelope for the waveform you can do much more interesting things with envelopes than that especially if you want to get nasty noises but you can muck with the attack decay sustained release and RG Touch makes that easy tremolo is really another wave envelope generator except it's usually constant tremolo is changing the volume over time and you can change it sinusoidally so it's like that wasn't very good so the volume gets higher and lower you can also do it in a square wave so it's just on, off and you can do other waveforms too and if you do it really really fast faster than the pitch then you can get super crazy sounds and that's really what FM is all about and it's pretty interesting portamento is somewhat similar to tremolo except it's changing the frequency over time and it can go much faster or much slower and if you do it super fast then you get lots of interesting things too actually I'm sorry tremolo isn't FM changing the portamento quickly is what FM is and then envelopes you can do lots of very interesting things beyond just ADSR and tremolo you can do all sorts of very interesting waveforms to change the envelope and then filters like base and treble control people know what those are those are high pass and low pass filters we can also have band pass filters only let frequencies through in the middle and you can mess with those over time fast or slow and you can also have a filter in digital that you can't do an analog which is just taking values and randomly changing them and then you get really cool totally horrible wonderful noises and you can tell I like noise I like noise and then effects you can add all of these together and you can have all sorts of interesting effects that ones that correlate with the analog world like guitar effects pedals or ones that you just make up on your own and without you touch I have a bunch of stuff like that and I make it really easy to add these dynamics just by calling a function I wanted to go over how the keyboard works the keyboard is just pads on the board these are just pieces of copper from the board and I coated them with a very thin layer of gold so they wouldn't oxidize but you just touch it and it plays the note you can also use the keyboard if you program it as a controller rather than playing sounds you can use it for changing the dynamics of the sound but the way this works is through capacitance and capacitance are like little teeny very teeny batteries that charge up really quick and discharge really quick everything has capacitance the pads on the board these pieces of metal on the board have capacitance very little but it has some so we can charge those capacitors up these little teeny batteries charge them up they'll charge up really fast and then we can discharge them fast if we touch the key that adds capacitance to the key you're touching and so that's a bigger slightly bigger battery and it charges up a little slower and we can measure the difference between the charge times and here's a graph of that the green one is charging up with just the piece of metal on the board the red one is charging up with you touching a key there's a difference and we can detect that with a microcontroller so we know which keys we're pressing right now I just have it only one key at a time but I could change that and I want to change it so we can play polyphonic the synthesizer itself underneath all of this is polyphonic we can have lots and lots of voices at once before the microcontroller which is actually quite low powered microcontroller for such a low powered microcontroller and then the other part of the board is the amplifier and speaker and this also has the cheap low pass filter which is one capacitor and one resistor per channel but the chip in here is a really old but still working chip called the LM386 it's a half watt amplifier chip and I use the least number of parts possible for it and I also have a headphone jack so we can have a line out and I have line in quotes because it's actually too too high an amplitude too much volume for line to do it for real I'd have to add another chip in there and op amp and I wanted this to be as inexpensive as possible so but it does work you can plug that into a nice amplifier and get super nice sound and the example I played earlier is from line out so the Arduino library that I made for RGTouch has lots of examples if you go through examples 0 through 9 then you can learn how to make your own synthesizers with my library and for example you can make really easily a sawtooth keyboard so this one this is the complete synthesizer including the comments that's the complete code it's looks quite simple and following the examples you can do this and you can have sawtooth output just by playing the keyboard you can change octaves with the buttons make it higher lower octave and you can change the volume you can from there if you want to add dynamics you know all the things I talked about for tremolo portamento etc and here's another demo and I do want to say you don't need my board to use my code this will work on any Arduino at all mine looks like an Arduino Uno but if you have a more powerful one then you have more input output pins it'll work on anything it doesn't come of course a regular Arduino doesn't come with a touch keyboard and a little amplifier but here's a couple more demos here's one that's totally different than the one it comes with all you need to do to get this one in is using the Arduino environment macOS windows or linux and download one of mine or create one of your own synthesizers and program it in takes a few seconds here's a demo called this mantra it plays a drone with a drone and an Indian-like scale so that you can't play any wrong notes because every note fits with every other note and all those voices are just played in real time calculated from wavetables and it's kind of cool here's one that's totally different this one's called ZOID for you noise lovers in the audience and it can make lots of different noises and the knobs change the noises and it goes on for a while and you can play it for a bit press into keys make different noises there's also presets to make very different sounds noises and you can just jam with this it's pretty crazy so that gives you an idea of some of that and you can't do this with digital so this is purely with analog you can't do this or you can do all sorts of crazy things like this but like this sounds almost bell-like and it's really an accident because I'm just like doing weird things to the bits to change the sound kind of randomly and um yeah so that gives you some idea The RG Touch has a lot of limitations because it's only a $30 little board with a very low powered microcontroller there aren't many input-output pins so I can't I only have two LEDs and I can only have two knobs and two buttons if I had more input-output pins I can do lots of things like add MIDI I can add a display I can add a bunch of things and I want to do that I have one file in the library which is for the Arduino Uno if I use a much more powerful microcontroller I can just change that one file and add lots more functionality and I'm working on that now there's also not much memory the microcontroller only goes at 16 MHz it only has 32K of program memory so the synthesizers can't be too big and it only has 2K of RAM so these are all limitations but if I use something like an STM32 or any kind of ARM core built in USB it won't be a kit anymore because the parts are too small for beginners to do so I can do lots of things with more RAM and built in USB and have some cooler library functions and have MIDI and all these other things so look out for that as I have time between travels all this is available on my github so if you do anything cool definitely let me know like I said earlier I'll share it with other people and it's all free go for it do you want soldering or want any kits I'm going to be over in the hardware hacking area doing more soldering and I can teach anyone to solder really well for the rest of your life so come on by if you want to until they kick us out today so that's it for my little rant thanks okay we have time for questions if anybody has any questions what was the purpose of the LEDs on the board? the LEDs so the LEDs there's for programming an Arduino it programs through serial and so there's an LED for serial in and an LED for serial out if you're not using the serial for your synthesizer which some synthesizers I made you can and you can control it with just a dumb terminal and do interesting things or your own like controller through serial but if you're not using that then the indicators can tell you what mode you're in like there's only very few controls on the RGTouch two knobs and two buttons so I can put the knobs in a different mode so instead of doing attack and decay I can have it do change the timbre of the sound and change the volume for instance and red light will turn on when you're like that blue light will turn on when you're in another mode both of them are blinking when you're in a third mode and things like that it's not the best user interface but I make use of what I have with an inexpensive low power microcontroller more questions how do you plan to tackle polyphony? polyphony? so with the low power microcontroller the max I can have at any given time for independent voices before the speed of the microcontroller is a limitation and then you get glitches which sometimes are kind of cool if you like noise but not if you don't want them more interested in the detection of pressing multiple buttons ah right so I just go through each one and I look at this key is it being pressed? yes no look at the next key is it being pressed? yes no and they can be put in a small table and that's going much much quicker than our human timing and you won't be able to tell there's any lag at all so that's rather really really slow compared to all the processing going on for generating all the sounds so that shouldn't be too hard but I didn't really design the interface with all my Arduino library functions to be able to handle that so there's going to be some a bunch of rearranging things to make that happen that's the hard part how is it to import your I'll do touch library in something like MicroPython import to what? import to something like MicroPython I think the badgers have got MicroPython on them all our EMF badgers so I haven't had time to look much at the EMF badge unfortunately so I don't know what processor it has if it's Arduino compatible and there's a board file you can download for the Arduino environment then it would be trivial because you just might have to change a few things I think in 2016 we had MicroPython running on it instead of the I assume it was on top of the Arduino thing but a lot of people might want to keep MicroPython on there so just wondering whether you can import a a C include file into MicroPython I don't know MicroPython well enough I really don't know Python too much for me C is a high level language but this is written in C++ so if there's a way to interface C++ with MicroPython then you can have MicroPython shells a layer on top of it then you can do lots of interesting things for user interface the board's microcontroller definitely has a lot more input output pins and a lot more memory and a lot more speed so it could be able to do lots of interesting things and I did notice as our Harold pointed out there's a synthesizer on the badge but it says it's not working please check later so if anyone works on that and gets it working I'd like to play with it but that one I presume is written in Python Any more questions? Comments? Comments, yeah The synthesizer does work on the badge but it makes an awful noise I enjoyed it but it was a I want to just do one more example here This one's called Arpology and it does arpeggios can change the attack and decay and you can go up and down octaves and then you can change here's another mode and you can see the red light turns on now I can use the pots to do change the pattern and I can change the speed make it slow or fast and then you can just play with it and if you want to you can tell it to play itself and it has a random number generator in it so it will never repeat and it has Bach-like modulations modulation in this case meaning changing key and musical so that's one of the many synthesizer examples that I have available on my website oh yeah let me show you where to get the website as far as my website if you go to the projects tab then you get my long horrible page of lots of projects all open hardware and there's this one and there's lots of stuff including really good assembly instructions lots of demo videos and each synthesizer you can download the instructions on how to use it or there including this one and the others I showed plus some others got a question? yeah I just wonder how easy would it be to hook up a clock input into it with other instruments perhaps or was that a modification that could be there? that would need another input-output pin and I'm using all of them at the moment but if you take away some of the functionality that frees up an input-output pin one thing that a friend did in Croatia actually is he took away the touch keyboard which needs one input pin per key and did a bunch of buttons and with a bunch of buttons you can do that with way fewer input-output pins and that freed up some input-output pins to do other things and then you can have that sync up to another argy touch or another synthesizer just following on from that last question I was thinking if you do have the serial header exposed so you've got the serial input could you not take a midi clock in through that without having to free up any other pins? well that's an interesting midi really is just rs232 but this is an rs232 it's TTL level so with just a little bit of circuitry on the outside converting plus or minus 12V into 0 to 5V we should be able to add some of that functionality in that's an interesting idea and also it's a weird baud rate but this is programmable baud rate so it's not a problem okay cool with a number of questions just quick reminders music amplifies off by 11 tonight and volunteers for the bar would be greatly appreciated tonight especially and feedback on emfcamp.org slash feedback I think but thanks again, thanks very much to Mitch


Ladies and gentlemen, the ceremony will begin momentarily. Good morning on behalf of Officer Training Command Newport. Welcome to the graduation ceremony for Officer Development School Honor Class 24020, consisting of 180 officers led by class team. Myself, Lieutenant Mikayela Barter, Lieutenant Justin Purnell, Senior Chief Information Systems Technician Gregory Johnson, and Chief Aviation Bocimate Manuel Gardugno. Military guests in uniform, this will be a covered ceremony. The order of events for this morning's ceremony are as follows. Commander Kurt Nielsen, Director, Officer Development School, and Rear Admiral Michael Steffen, Commander, Navy Reserve Forces Command, will arrive shortly. The guests in class will rise for the arrival of the official party and remain standing for the playing of the national anthem and invocation. Commander Nielsen and Rear Admiral Steffen will then address the graduating class. Following their remarks, class awards will be distributed to recognized students and graduates will symbolize the completion of their training by returning their respective company guide-ons to their class chief petty officers. The class will then reaffirm the oath of office and will remain standing for the playing of the service songs and the final dismissal. Please rise for the arrival of official party and remain standing for the national anthem and invocation. Commander, United States Navy, arriving. Navy Reserve Forces Command, arriving. Ladies and gentlemen, our national anthem. Chaplain Everts will now offer the invocation. Eternal Father, strong to save, we give you our thanks for binding the restless waves within each of these newly trained naval officers. So they could stand proud this day for becoming morally, mentally, and physically developed for the service of our fleet. As they prepare for their next evolutions in their communities, remind them of what it means to be a leader and to serve with a purpose. Let them embody humility and selflessness. Remind them to value every sailor and civilian they cross paths with each day. Oppress upon them the initiative, integrity, accountability, and toughness needed to do the right thing, especially when it's difficult. And bolden them to have ownership of what they are called to do, even when they are called into harm's way. So as these officers look to the horizon, prepare them for the challenges that lie ahead, giving them the physical, mental, and spiritual readiness to meet each one with confidence. And as we continue to celebrate this moment, we ask for your spirit to reside with us and all those who stand the watch this day. In your name we pray. Amen. Please be seated. Ladies and gentlemen, Commander Kurt Nielsen, Director, Officer Development School, Officer Training Command Newport. Admiral Steffen, Ambassador Emanuel, Ms. Valentino Smith, Captain Russell, Captain Beard, Captain Pearson, Captain Gible, Captain Gustafson, distinguished visitors, veterans, Officer Training Command Newport staff, family, and friends joining us today, and shipmates of Officer Development Class 24020. Good morning. It's an honor for me to have this opportunity to welcome this honor class into one of the most prestigious, challenging, and rewarding careers in our nation, that of a naval officer. Today we will bear witness as 180 officers renew a solemn promise to our nation, reaffirming their oath to support and defend the Constitution of the United States. For the families joining us, I want to both thank you and commend you for the performance of your sons and daughters, husbands and wives, brothers and sisters, friends. Your love, support, and encouragement have produced the quality individuals seated here, ones who chose a path of service to their fellow citizens. I could think of no finer group to go forth into the fleet than the officers seated here today. They could not have gotten to this point without the careful guidance and support of family. On behalf of the Navy and a grateful nation, please accept my most sincere thank you. To the class, I'm proud of you and all that you've accomplished while you're here. I have witnessed you all the past five weeks develop your leadership skills and come together as a team, especially during yesterday's culminating event. As you depart for your schools and duty stations, know that you are about to be placed in positions to lead and mentor what is truly the backbone of our force, the enlisted men and women of our Navy. The foundations we have laid here at ODS are solid. It is now up to you to build upon this as you enter the naval service. I am very impressed with the effort you have expended over the last five weeks, and it is my pleasure and distinct honor to welcome you to the Wardroom as professional naval officers in the world's finest Navy. It's now my honor and privilege this morning to introduce to you our guest speaker, Rear Admiral Michael J. Steffen, Commander of Navy Reserve Forces Command, Deputy Commander of Navy Reserve Force. Rear Admiral Michael J. Steffen is a native of Bedford, Virginia and a 1992 graduate of Virginia Tech. He was commissioned through the Virginia Tech Corps Cadets in conjunction with the Naval Reserve Officer Training Corps program and designated a Naval Aviator in 1994. He also holds a Masters of Science degree in Global Business Leadership from University of San Diego. His command tours include the helicopter anti-submarine squadron light 60, HSL 60 Jaguars, Jacksonville, Florida, the Maritime Support Wing based in Coronado, California, and Naval Air Station Fort Worth Joint Reserve Base, Texas. He has flown over 125 combat missions in support of Operation Iraqi Freedom and accumulated nearly 3,000 hours of flight time with over 1,000 hours of night vision goggle time. His leadership is essential to the continued success of the world's greatest Navy and we are fortunate to have him here with us today to share his thoughts. Ladies and gentlemen, please join me in welcoming our guest of honor today, Rear Admiral Michael J. Steffen. Awesome, hey, thanks for the kind introduction Kurt. Can I adjust the microphone here? Got to get Mike checked, everybody hear me in the back? All right. All right, well, good morning distinguished guests, family members, friends, shipmates, and most importantly, the graduates of the United States Navy Officer Development School, ODS Class 24020. And the first order of business is to put the class at ease. Everybody relax, everybody's, I mean, the instructors did a great job.  I got some questions for you here in a minute too, and I'm glad. Well, let me start by saying that I got some exquisite signals intelligence about the ODS class discussion surrounding the planning of this ceremony and how good it would be if it only took about 30 minutes, depending upon how long the guest speaker talks. Well, normally I keep it short, but I don't want to disappoint all the family and friends that have traveled so far, especially Ambassador Emanuel, came all the way from Japan. To make sure, I want to make sure everybody gets their money's worth out of this speech here, so relax, sit back, get comfortable, we're going to be here for a while. No, seriously, I will keep it relatively short because I realize the only thing between you, civilian clothes, and a good meal is me. And so I'll try to keep it short but mildly entertaining. It's fantastic to be here and with great pride that I stand before you today in Newport, a hallowed place synonymous with the development and commissioning of the Navy's finest officers. As we gather here for the moment this occasion, I'd like to recognize our distinguished visitors, Ambassador Emanuel, from one of our most important allies and partners out in the Pacific, Japan, Miss Valentino Smith, the Director of Defense State Liaison Office, and we have numerous Navy captains, both active and retired in civilian GS-15s whose attendance is a testament to the generational commitment to the service that defines our great nation. Their support for their family members upon graduating class today underscores an enduring bond and shared dedication that spans across the ranks and roles within our Navy community and country. To all the parents and close family members, a special thanks to you for not only coming out here today but raising such amazing young adults and strong leaders, instilling in them the foundational values and work ethic, and entrusting them in the care of the U.S. Navy where they will thrive and have an opportunity to lead the world's finest sailors. To the ODS instructors, thank you for your endless hours of patience, dedication, and setting the foundation for our junior officers to succeed. And of course, to all the members of ODS class 24020 who we are here to recognize today, by the way, I heard a rumor that this class has a nickname and they nicknamed itself after one of my favorite childhood TV shows. So let me ask ODS class 24020, is it true that you call yourselves the Thundercats? And are the Thundercats a highly motivated group that achieved honor class status? And are the Thundercats going to be the next generation of leaders our Navy and our nation need? Yes, sir! Oh man, that's outstanding. It sounds like we're in really good hands, right family and friends? Standing here today, looking out into the faces of this graduating class, I'm filled with a profound sense of optimism and inspiration. It seems like just yesterday I was in your shoes preparing to embark on the adventure of a lifetime and I fondly remember my training in the Virginia Tech Corps of Gidettes which I believe had many similarities to ODS. Things like early morning PT, late night watches, and stern drill instructors with keen eyesight that seemed to detect every flaw in an otherwise impeccable uniform. I had Staff Sergeant N.A. Toe who was a Samoan big muscular recon Marine whose only English words were cuss words, by the way. He was one of my drill instructors and set the foundation for me. I also had to deal with questionable cuisine at the Chow Hall with the tiniest portion sizes that will ensure everybody drops a few pounds through training. And in fact it seems like some things never change when it comes to officer accession programs. So I practiced my information warfare skills and I did a little research to figure out what exactly were the training conditions here at ODS. And I did it through a super reliable source called Google Reviews. And believe it or not there are reviews on ODS. And here's a couple of the posts I want to share with all the family and friends and the guests today on Ne Hall, the dining facility. First review, one of the better Chow Halls in the Navy can get a bit loud at times and if you're lucky you'll be treated with a song and a dance routine. Rude patrons and confusing entrance procedures also the cheese steak has no cheese. People literally line up here for hours so it has to be good. In fact I'll probably come back tomorrow and the next day and the next day and the next day. So then I transition to the King Hall reviews which is the residence hall. First review says wake up calls are early and intrusive. Heat on blast makes you sweat in the winter which encourages you to clean common areas if your bed isn't made they throw you out. King Hall, I love this is one of my favorites. King Hall is older than my parents and functions even older. Extremely hot in the summer and hot in the winter there is no mercy shown by this old building to its inhabitants. Fantastic haunted building definitely worth a visit. Spooky basement with creepy mannequins that haunts the upper floors by rattling radiator pipes around. And finally older than Moses. Full of young people who are learning to march and maintain their bearing but if you have the privilege of staying here you realize you're not here to be served but to learn how to serve. Now I'm going to dwell on that last comment for a minute because it's incredibly insightful, wise and in contrast to the humor that preceded it. It's precisely why you came to ODS. Not to be served but to serve and learn how to serve. Service to our nation is a noble calling one that you have answered with courage and commitment. The uniform you wear is not just fabric and thread it is a tapestry of our nation's history and the sacrifices of those who have come before us. You are now part of that story tradition guardians of our freedom and defenders of the Constitution of the United States of America. It started with taking your commissioning oath but I know ODS has made that oath so much more real and your experience here is something all commissioning sources share the Naval Academy, ROTC, OCS that bring us closer together with a strong bond that is forged by military service. Now as a junior naval officer you are about to embark upon a magnificent journey and I can't even begin to describe how excited I am for you and how adventurous it's going to be. To give you a slight taste I'll describe to you my first six months in the real Navy after flight school. I just taken deployment on the nuclear aircraft carrier the USS Carl Vinson. We departed San Diego in the spring of 1996 and made port calls in Japan, Hong Kong while the British were still in charge Singapore, the jungles of Malaysia, Kuwait, Saudi Arabia, UAE and then Australia and Hawaii on the way home. We conducted operations across an entire spectrum of naval warfare mostly in training with our allies and partners but also participated in operations Southern Watch for Saddam Hussein from attacking his neighbors and his own people. We battled rough seas and intense weather conditions but also got to experience cultures from around the world and I saw such majestic things like a pod of blue whales out in the South Australian Bight from my helicopter and got to experience an awe inspiring view of the Milky Way in the middle of the Pacific thousands of miles away from any light pollution on the deck of an aircraft carrier and most importantly I made lifelong friends and shipmates that have turned into my extended family and this was in one six month deployment for a young farm boy from Virginia this was an amazing and educational experience that no amount of years at a university could ever replicate the good news is you all are going to have the same similar experiences but each of your adventures is going to be unique for our information warfare officers find yourself in Bahrain at Fifth Fleet headquarters working in a targeting cell that supports operations in the Red Sea our medical corps officers might get called to support special operations in Africa our Jags will undoubtedly spend time in the Indo-Pacom area of responsibility advising our Navy leadership on operational laws that applies to the freedom of navigation and territorial waters but regardless of your warfare specialty the work will be meaningful and the impact on our nation will be very positive and very impactful you will navigate uncharted waters both literally and metaphorically but remember it is through these experiences that you will grow as leaders and individuals I also urge you to remember the lesson you learn here probably more than any other and that is teamwork no one succeeds alone every team member has value from the most junior enlisted person to the most senior flag officer treat everyone with dignity and respect you are a highly talented group of people and you're going to get to meet many more because the Navy is full of them start your networking now with everybody that you met at ODS you will continue to bump into and rely on one another throughout your careers in these relationships to get things done it's one of the reasons that the Navy is so awesome you never say goodbye to your friends you just say until we meet again through this teamwork you don't need to be afraid to take calculated risks your actions are going to set the tone for your sailors under your command and your example will inspire them to strive for excellence so the path you've chosen will not always be an easy one but it will be noble and just and just take a look at the news and I can think you can see why it's so important to do what you're about to be doing today a resurgent and aggressive Russia that has ignored its neighbors' sovereign borders with a brutal invasion of Ukraine by intimidating and destabilizing others moving to the Pacific theater in the Chinese regime and its autocratic leader Xi Jinping who has consolidated his power to become the sole decision maker of 1.4 billion people and is challenging the international rules-based order through coercive and aggressive means the US Navy in cooperation with Japan along other allies and partners play a critical role in maintaining the stability and curbing aggression in the Indo-Pacific region shifting to the Middle East the hotspot that never seems to cool down the Israel-Hamas conflict has led to a precarious regional security environment that others in the area are seeking to exploit and in this regard I would encourage everybody in here to check out recent news clips of the media embarks that occurred on Navy ships operating in the Red Sea that highlight our sailors in action to defend our nation's interests very soon these sailors that we see here today could be in those very news clips later on this is a snapshot of the security environment we're in and while we remain optimistic there will be diplomatic solutions to address these challenges we have to be ready on day one if called into harm's way and today is also somewhat of a passing of the torch with more than a dozen current and former service members and civil servants who have children in this class including the ambassador and myself we are incredibly proud you in this entire class are the embodiment in hope and promise of our nation ready to lead with honor, courage and commitment as you stand on the cusp of this new adventure know that you carry with you the trust and expectations of those who are served before you and the aspirations of those that will follow and let the knowledge that you are part of something greater than yourselves be the wind in your sails as you embark upon this grand voyage you have the watch as I wrap this up I want to give you a first bit of advice and guidance from a weathered old admiral immediately following this ceremony your first order is to take time to thank the people that helped you get this far start with the people that are here boyfriends, girlfriends, spouses, parents, friends, family being here is a testament to their investment in you and in our nation your instructors too being tough and demanding is their job and critical to your development your success is their success and then branch out to those that couldn't make it but still had an impact on your success your teachers, coaches, and other family members church leaders, community leaders and then never let that graciousness fade because you rely on these same people to help you through more training and eventually deployments overseas and always remember being in the Navy is the ultimate team sport congratulations graduates may your careers be as inspiring and limitless as the promise I see before us today Godspeed on your journey may fair wins and following seas accompany you always God bless you, God bless our Navy and may God continue to bless the United States of America thank you thank you Commander Nielsen and Rear Admiral Stefan at the conclusion of each ODS class several students are recognized by their fellow classmates as well as OTC and staff for outstanding achievement during the five week course of instruction Lieutenant J.G. Jonathan Cipolletta front and center the honor student award is presented to the officer who best demonstrates an overall excellence in the areas of academics, physical fitness and military bearing consistently setting the example for his or her peers throughout the many challenges faced at officer training combat the honor student award goes to Lieutenant J.G. Cipolletta Lieutenant Lisanne Pomperata front and center the Alfred award is given to the officer who achieves the highest military grade derived from personnel inspections, room inspections and general military bearing this award is named after the Continental Supervore the Alfred commissioned in 1775 the Alfred served as the flagship of native Rhode Islander Commodore E.C. Hopkins and is regarded as the birthplace of Navy medicine as it was the first ship to appoint a dedicated ship surgeon serving as a role model of Navy pride and professionalism maintaining the highest military standards and providing inspiration to all the Alfred award goes to Lieutenant Pomperata Ensign Andrew Mate front and center the Pickens-Wills peer leadership award is presented to the officer who personifies the highest standards of personal example good leadership practices and moral responsibility officers were nominated by their peers and the winner was selected by the officer training command staff the winner of this award embodies the leadership traits and esprit de corps of Harriet Pickens and Francis-Wills the first two African-American women to commission in the United States Navy their courage and collaborative leadership paved the way for today's inclusive Navy the Pickens-Wills peer leadership award goes to Ensign Mate Lieutenant J.G. Kaley Dryden front and center the E.D. award named for Lieutenant Thomas E.D. United States Navy recognizes the highest achievement and academic and military performance Lieutenant Thomas E.D. who immigrated from Scotland and settled in Rhode Island was awarded the Navy Cross and the Medal of Honor for his courageous efforts as a diver during the salvage of submarines SS-4 and SS-51 off the coast of Massachusetts he was a member of the southeastern New England chapter of the retired officers association at the time of his death in 1974 in recognition of this accomplishment in addition to a certificate of achievement the military officers association of America has also provided a three-year membership to the E.D. award winner Lieutenant J.G. Dryden for the past five weeks the company guide on has been a symbol of spirit, dedication, teamwork and unit identity to symbolize the fact that these officers seated before you have completed their training they will return their guide-ons to their class chief petty officers senior chief information systems technician Gregory Johnson and chief aviation bossamate Manuel Garduña officer Lieutenant Pernell will now deliver the reaffirmation of the oath of office with all military personnel in uniform please come to the position of attention director of officer development school officer training command Newport would like to present to you your all newly reaffirmed naval officers for officer development school graduation honor class 24020 ladies please give it up ladies and gentlemen please rise for the playing of the service songs and the final dismissal officer development school honor class 24020 upon graduation from officer development school you are ordered to detach your report to your duty stations where you will assume your duties and responsibilities by order of Everett Alcorn captain United States Navy commanding officer officer training command Newport ladies and gentlemen this concludes our ceremony on behalf of the commanding officer officer training command Newport thank you for attending today's graduation ladies and gentlemen please remain behind the blue rope until class photos have been taking following class photos will all