.wav Tempo Change


I recorded a track of acoustic guitar and I need to speed up the tempo. when I try to speed it up the midi tracks are all that speed up the wav file keeps the original tempo. How do you change the tempo of a wav file?


What did you do exactly when you tried to speed up the tempo of the acoustic guitar track? Did you try adjusting the bpm which shows the default at 120? If so, this will only adjust the midi tracks.

One way to adjust a wav track is using the Time Stretch option under the Track menu, then Special, then time stretch. I am not that familiar with it but it seems you can adjust the BPM but you have to choose it in the drop down arrow menu.

hi IT, and welcome to N.

Syn is right; a WAV file doesn’t respond to a tempo change. Only MIDI does that. There are utilities that stretch existing WAV files, but the end result isn’t near as good as redoing the part. N has a Stretch function, as do most nicer WAV editors.

Which editor are you using?


Thanks for the info. I use sound forge xp for my wav editor. I am not sure if you can adjust the tempo with it or not but I will try.

I’m pretty sure SF has a Time Stretch function. Just so you understand, this isn’t the same as adjusting a tempo. This actually stretches the WAV file to a new length. The result is a slower song.

Usually, when stretching a WAV, both tempo and pitch are affected… stretch a WAV, and the tempo and pitch both are lowered. Shorten a WAV, and tempo and pitch are both raised. But i think you’ll find that SF gives you an option to retain pitch. If you select it, SF will attempt to maintain the same pitch while stretching or shrinking the WAV. You lose some sonic clarity, of course. But SF is a good product. It should do a decent job.

Actually, it’s a great product. Far too expensive for my budget. How much did you pay for SF?


Hey Teej,

Most online sellers have SF 7.0 for $249 these days…but watch out…SF 8.0 is coming in April. I figure It’d be better snap up 7.0 while the price is down…


Thanks, TG. That’s actually less than i thought it was. Still, WaveLab has been working fine for what i need.

Yup… i’m cheap! :p


Actually I’m using SF 4.5. It came bundled with my ADS Instant DVD software package which cost around $99. I sure would like to have version 8 but it is out of my budget range.