A USB sound card can serve as a cheap, consumer off-the-shelf ADC, a technique pioneered by Marek Dolleiser. Specialized computer software performs pulse-height analysis on the digitized waveform, forming a complete MCA. Sound cards have high-speed but low-resolution (up to 192 kHz) ADC chips, allowing for reasonable quality for a low-to-medium count rate. The "sound card spectrometer" has been further refined in amateur and professional circles.