Change Mp3 Tempo (not Pitch)

What’s the best way to change the speed of a complete song (mp3, wav) without a change of pitch and with the least possible loss of quality? I’m currently using a terribly old version of Cool Edit Pro, but I’m wondering if there are better solutions?

use adobe audition for timestretching

audacity is a free program you could try.

dunno about the quality of doing that on an mp3 tho.

celemony melodyne is the shit tho.