I use state of the art software so there will be no artifacts if the target BPM is near the source BPM. There will be some quality loss when these BPMs are far from each other.
Here you have some case scenarios:
1.- You want to learn a guitar solo but you can't because it's too fast. I can slow the audio down by 50% and you will hear every note in detail! In these extreme cases (50% BPM change) there will be some quality loss but it doesn't matter because this is only for studying the guitar solo.
2.- You have a song with BPM = 118 but you would like it to be 120 or 116. I can do that with no quality loss or artifacts.
IMPORTANT: Please send me the audio file and slow down percentage for an evaluation and free demo before placing the order.