A program that uses Marsyas to do various types of audio processing/digital audio effects that takes as input a single audio file and generate a single audio file that is the result of the processing.
Help info (this should give you all the parameters that you can adjust from the interface):
Bandpass filter with center frequency 500 Hz and a q-factor of 10 the file input.wav processing 30 seconds starting 15 seconds into the file with a gain of 0.8 and write the result to output.wav
sound2sound input.wav -m bandpass -f 500 -q 10 -s 15 -l 30 -g 0.8 output.wav
sound2sound input.wav --method bandpass --frequency 500 --qfactor 10 --start 15 --length 30 --gain 0.8 output.wav