Audacity

Audacity is an excellent, free program, designed to edition of sound files. The main available option are recording and reproduction of sounds, as well as import and export of audio to format as mp3 (it require codec LameMP3, which must be install earlier) WAV, AIFF or OGG. Audacity enables edition in real time, shorten sounds, addition of simple effects (echo, after sound) remove of murmurs, normalization, strengthen of signal (amplifier) In addition the program support effects VST and LADSPA and also possess module display spectrograms, which are used to analyze of frequency. Application is available in English.