Decoding phone line signaling: DTMF tones Caller ID so-called Automatic Number Detector (using in former USSR countries); Fax messages decoding; sound processing: automatic gain control, denoising; database with password query mode and records selection; selected records can be saved in other folder and later can be loaded to the database again with all information (dates, notes). So, user can record files in one computer and process them on another one. Embedded player with audio view and audio processing (AGC, spectrum inversion, equalizer); Sound file ciphering mode (ciphered sound files can be played by embedded player only); RecSound Core can be installed in Windows service mode; Automatic erasing of old files, keeping stetted percent of disk space free; Recording audio fragments in one file with time of each fragment saving. (This is useful in radio nets with little traffic recording); Circular buffer (recording audio information which has been sounded before the record was turned on). You don't lost any second of audio information! Stealth mode of RecSound Core. (RecSound Core is not visible even in Windows Task Manager's process list).