Sony PCM-M10 Professional audio recorder
The truth is this Sony PCM-M10 professional audio recorder is cheap, only $400.
It is an audio recorder, dual electric condenser microphone for each channel (96 kHz/24-bit) with 4GB of internal memory and a buffer of 5 seconds of recording. It has a speaker to reproduce the recordings, with USB 2.0 connection and recording in WAV or MP3.
The memory of Sony PCM-M10 can be expanded with microSD and Memory Stick Micro cards, which will surely need. The good news is use AA batteries.
