I am going to be doing some beam forming. I understand the concept and plan to record all the data then analyze the signals from multiple microphones to figure out locations of some noises (there will be multiple locations per trial). I am stuck on how to record the data from multiple microphones at the same time. I can use a computer or a designated micro controller to do this. I plan on using 3 to 10 microphones.
Thank you in advance.
The problem you're imagining doesn't exist, unless you create it. If you use a PC with a sound card with a multi-channel input, you will get frames of data where the samples from each channel are aligned. If you use a microcontroller, you can do the same thing yourself, provided the chip has enough ADC channels, and you can start the conversion on all of them at once (or close enough as doesn't matter). Other than responsiveness, it doesn't matter what order you copy the data in, or how long it takes to process; it only matters that all of the samples with the same index were sampled at the same time.
I did my masters thesis on this. We used an FPGA, so all the sampling could be done in parallel. Processing was done in real-time, with only the directional data actually reported anywhere. That eliminated a lot of the storage and time-stamping concerns.
Here is one device a Google search turned up...records 16 live channels for you; costs about $400.
Otherwise, if you're more the "DIY Type," a search of Digikey will turn up several MCUs with 20+ ADC inputs that'll record at up to 1MHz or so. I've been considering a few of them that cost less than $10 USD/ea for a multi-channel audio speaker sync. delay + recorder project that I'm working on.
