Time-scale Modification using the Phase Vocoder
Florian Hammer · 2001
The phase vocoder has been used as a time-scale-modification tool for several decades. Applying large positive modification factors to different kinds of sounds (time-stretching), the result will always sound "phasy" or "reverberant". The sound quality can be improved by "locking" the phases. Phase-locking preserves the phase relations around a local maximum in the magnitude spectrum. For large modification factors, locking the entire phase spectrum sounds "rigid".