Sony ICD-PX232 2GB Digital Flash Voice Recorder Format(s) Supported - Recording - MP3 files - Bit Rate - 8 kbps - 192 kbps, VBR File Extension -. mp3 Frequency Range - MP3 192k (SHQ) - 75 - 15,000 Hz MP3 128k (HQ) - 75 Hz - 15,000 Hz MP3 48k (Mono) (SP) - 75 Hz - 10,000 Hz MP3 8k (Mono) (LP) - 75 Hz - 3,000 Hz Microphone - Built-in, unidirectional microphone Recording System - Digital, Monaural Recording Microphone Sensitivity Feature - Yes (Hi/Lo)