Equalize beat gapping of all over an mp3.

Hi! to all.

I have some odd songs in my collections. These songs are not equal in beat gapping or length of a beat i.e. the duration from one beat to another. For example, if I select a beat phrase (starting point of up-beat to starting point of down-beat) from the beginning of the song, the selection length shows 0.48 sec, but in the middle of the song if falls in 0.52 sec and somewhere it shows 0.46 sec.
Is there any trick or process to equalize the gapping difference by increasing or decreasing the tempo beat by beat?

Not that I know of.

You got these songs from internet download, right? You didn’t perform them? It sounds like whoever was doing rhythm was doing it live after a difficult night.


Audacity does not have effects specifically for beat matching or tempo quantizing, but you could try the “Sliding Time Scale / Pitch Shift” effect to gradually stretch the tempo as required. http://manual.audacityteam.org/o/man/sliding_time_scale_pitch_shift.html

It’s not that unusual for the tempo to drift around a bit. Most modern music is recorded with to a “click track”, but most older music was not. And, most musicians don’t play to a metronome. :wink:

Sometimes the tempo is intentionally altered for artistic reasons.

There is a lot of programmed MIDI in modern recorded music, and of course most MIDI music is timed-perfectly. Sometimes a “humanize” effect is used to add some randomness to the timing in an attempt to make it sound less computerized.

If real instruments are mixed with MIDI, the real instruments have to be exactly timed with the MIDI.

And/or a click-track is used so all takes are played at the same tempo allowing the engineer/producer to “comp” (compile) a final mix by combining parts of different takes together.

Thank all of you.

But playing with different values in “Sliding Time Scale / Pitch Shift” doesn’t help me much.
Is this feature to be introduced with upcoming release?
I have heard about ‘Elastic Audio’. Does it work with this problem?

because you can’t find the right numbers?

There are currently no plans that I’m aware of.

Many (non-free) DAW applications include features to assist with beat matching and tempo quantizing. The terms used to describe the effects vary from one program to another.

So I’ll record your “votes” for these.


Please give me some examples to find it to get accuracy. The manual doesn’t give so in details.


If you use the Length boxes in Change Tempo you can get a readout of the percent change required for that selection, then apply that percent change in Sliding Time Scale. You can’t use Change Tempo itself because it is not length accurate.