a REALLY easy way though, assuming you will use adc~ to record....
use makefilename and a counter so that you will make filenames like 1-piano.wav 2-piano.wav etc...
and then add [env~] after [adc~]
if [env~] goes above the threshold level of your room noise, then trigger a bang to the counter to make your filename, and then trigger a bang to open the file, and then finally trigger a bang to [writesf~] (or whatever object you prefer to use to record)
when env~ returns below the threshold, you wanna trigger a close to your write object.
eventually you get a whole bunch of files 0-piano.wav, 1-piano.wav, 2-piano.wav..etc
much more user friendly!