A little more involved way of doing this as you know in a pulse velocity test, you could either have the receiver and transmitter placed on two sides of the wall, we call that the direct measurement.
ह्या टेस्ट साठी ट्रान्समीटर आणि रिसिव्हर हे भिंतीच्या दोन विरुद्ध बाजूंना ठेवायचे असतात.