How to change the tempo/pitch without distortion
I've been having trouble changing the pitch or tempo on music files (MP3) without hearing unpleasant distortion as a result, using Audacity.
The original files are fine, but once modified and played back, there is an obvious distortion. Hard to describe, but they have a certain "jumpy" sound.
Originals are typically around 3M per track, 128k bit rate. The music is provided legally for church use, but higher quality files aren't available - in other words, this is what I have to work with.
This is traditional church pipe organ music with deep bass and the problem isn't noticed on the laptop or with decent headphones, but on a playback system with more bass it is obvious.
I'd appreciate any suggestions on how to do this.
1. Can it be done well with Audacity? If so, what might I have done wrong?
2. Is there other software I could use?
3. Is the problem that the originals are simply not good enough?
1. no, well... if you use varispeed you can do it without digital artifacts but the tempo will change with pitch.
2. Yes, I like Radius by iZotope but I am sure anything commercial will be better than Audacity.
3. It's not helping, but changing pitch or tempo will always have some artifacts.
I'm not familiar with Audacity but Logic Pro has a great flex tool with speed changing and other algorithms. It works the same as the pitch control on a cd player. But that's a DAW. About software: Radius indeed and maybe Celemony Melodyne (although I use the last one only for 'finding' notes in melodic loops or samples).