Can I use 2 microphones with pi? & receive those two input-signals respectively?I want to receive two sound signals respectively in raspberry pi. In this case, just plug in two usb-microphones and receive each signal? Please, give me some advice..
Yes, you can. You can either use a single USB audio device with stereo inputs (I use an old Griffin iMic) or use two USB mono inputs. I prefer the former — not just because I already have the hardware to do it — as it means fewer devices to support, and fewer potential sync errors between the audio streams.
For instance, I've used a Raspberry Pi, the iMic, and a binaural microphone set clamped to a 30 cm steel rule to demonstrate range finding by calculating the delay between the left and right channel signal.