From the documentation:
SndSampler is the ultimate shareware tool for recording, editing, and working with sound on the Macintosh. It's simple enough for the novice but contains many powerful features which will appeal to the sound-editing professional.
Download 1 and 2 contain SndSampler 5.4, the final version of this program.
Download 3 contains SndSampler 4.6.4, which I believe is the final version that will work with System 7, though that needs to be tested.
SndSampler will work on any Power Mac running Mac OS 8.5 or later and Sound Manager 3.2 or later. It runs natively on Mac OS X, with the recommendation that you have 10.1.2 or later installed. If you're running the Carbon version on a Classic Mac OS system, you'll need CarbonLib 1.2 or later installed in your System Folder. To use QuickTime functions you must have QuickTime 3.0 or later installed.