: High-quality, lossless files are preferred. Compression (like MP3) can "clip" or distort the peaks of the waveform, leading to inconsistent or "stinging" sensations rather than smooth pulses. Carrier Signals
: Many modern units can process standard music or ambient sounds. This allows users to "feel" the rhythm of a favorite song or the dynamic shifts in a movie soundtrack. Session Files : Some specialized software, like electro stim audio files