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I'm trying to create a prototype using a breadboard that is able to record sounds at the ultrasonic frequency range. I am looking into purchasing this microphone.

The problem is that the Raspberry Pi only has digital inputs. I researched and found this ADC. However, from speaking with the guys who run this company, they basically said that this would not be able to handle audio and is only used for simple analogue signals.

Does anyone have any ideas to where I can find a ADC that would suit my needs?

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First off, that microphone isn't going to work. It cuts out at 10 kHz, so is better suited to voice recordings. Ultrasonic is usually in the 50-100 kHz (and slightly higher) range. You might be better off with a MEMS Sensor. If you have an unlimited budget, the G.R.A.S. ⅛" microphone is the one to choose, but it's designed for professional acoustic work and is breathtakingly expensive. The cheap Panasonic WM61 might work, too.

You'll need a pre-amp and possibly phantom power supply for the microphone.

You'll need a faster DAC, too. If you want to limit your highest frequency to 100 kHz, the 200 kHz PCM1794A could do the job. It's used in the Rpi DAC audio board.

If you can give some more details of what you're trying to record, it would be useful. The higher you get above standard audio equipment, the more it costs; for instance, this “affordable” USB Ultrasound Microphone. If you only need to detect these frequencies, tools like the Simple Bat Detector can do this cheaply.

  • What I'm trying to do is develop a board that works along-side the raspberry pi. The board has Microphones where I can leave outside (battery operated) to record Bat sounds over a particular period (Obviously in Ultrasound). Any recommendations? I don't want expensive, USB microphones so would be ideal to be able to solider myself – Phorce Jan 10 '14 at 21:41
  • Did you ever get this setup working? I'm working on a similar project and I'd be interested to know what you found for hardware. – KFox Jul 11 '16 at 14:51
  • Panasonic WM61 and PCM1794A links have died. – rsaxvc Jun 22 at 13:51
  • thanks, @rsaxvc - link rot got to them, so I've replaced them with working Wayback Machine links. – scruss Jun 22 at 15:07
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I am starting on something similar. Here is an ultrasonic microphone mems you can buy from Digikey U.K. For a couple of pounds http://www.knowles.com/eng/Newsroom/New-product-Ultrasonic-MEMS-Microphone

This plus an opamp to increase the output to a few volts should feed the A2D converter a treat

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