Page 1 of 1
VocalFusion Stereo Dev Kit mic array elements spacing
Posted: Mon Jun 25, 2018 9:08 pm
by sluwindsor1
Hi, I want to buy the device VocalFusion Stereo Dev Kit, and I noticed that it has 4 elements with 33.33mm spacing, I would like to ask why XMOS set up this spacing and this geometry config? If I want to use this kit to capture higher frequency audio signal, should I change the geometry config?
Thank you in advance
Re: VocalFusion Stereo Dev Kit mic array elements spacing
Posted: Tue Jun 26, 2018 12:54 pm
by infiniteimprobability
Hi, the spacing has been chosen to provide a good compromise between performance and compactness. We originally supported a 100mm spacing but it was physically too big for many products.
All of our certification has been done on the 33mm spacing for linear mic arrays.
You can change the geometry using a #define in the source code. Bear in mind that going below 33mm will reduce the beamformer's ability to improve the SNR.
Regarding capturing higher frequencies (audio frequencies I assume?) the IP works at a fixed 16kHz sample rate so nyquist is 8kHz. The raw microphone PDM->PCM library (lib_mic_array) however can work up to 48kHz sample rate.
Re: VocalFusion Stereo Dev Kit mic array elements spacing
Posted: Tue Jun 26, 2018 1:30 pm
by mon2