Matching MIDI to audio

Can somebody just run through how to synchronise a MIDI track to an audio track. The audio track is played by humans and speeds up and slows down - a bit?

So if I take an existing track and want to sequence a synth part to match it. It is too complex to play in real time, so I write it in Sibeius or in … Cubase score. Then add it to the audio. I guess I can use the timewarp feature. Does anybody do this this and what are the pitfalls?

Stephen :nerd: :ugeek: :question:

Create a tempo track from the audio by using either:
-The timewarp tool
-Merge tempo from tapping
-The C6 tempo recognition tool

Import the MIDI file, without tempo information…

[quote=“thinkingcap”]Create a tempo track from the audio by using either:
-The timewarp tool
-Merge tempo from tapping
-The C6 tempo recognition tool


Thank you for your reply.

Of these three what have you found to be the best system? From reading the manual I would guess the C6 tempo recognition tool would be best with just drum tracks.

The tempo tapping tool sounds like a lot of editing for four-minute song.

That leaves time-warp.
So you would set up an approximate MIDI tempo, import it, then apply the time-warp to the MIDI track, leaving the Audio in … [I get them mixed up sorry ‘linear’ or ‘musical’ mode] and align the MIdi visually say on beat one of each bar, then go back over and tidy up the synchronisation for beats two-three four etc or other accents> Does that sound like the right work-flow? Do you normally work this way?
:nerd: :question:

I’m interested to hear a way to do this right that isn’t a lot of work for a 4 minute song!

For extensive discussion on how to do this, you may want to google search this forum for posts by vic_france and crotchety, throw the words “free-tempo” or similar in there to narrow down the results.

FWIW, I always do what you do - free tempo a keyboard recording, then apply MIDI parts to it. The way I do it is to :

  1. Create a tempo map that accurately follows the audio. I do use “Merge Tempo From Tapping” because the automatic tempo detection doesn’t work that well for my piano audio, but as you pointed there are other methods. I then tidy up the tempo map with the Time Warp tool so it exactly follows the audio.

  2. I then get the audio to play at a fixed tempo, temporarily so I can overdub MIDI. To do this, I apply the “Set Definition From Tempo” tool (after making the exact tempo map, above!), then deactivate the tempo track and put it at a fixed value, 90 or 93 beats per minute, etc. (i.e., at the tempo that the audio would be at without the nice free-flowing tempo variations). When the song is played back now, the audio plays at a fixed tempo.

  3. Now that the audio plays back at a fixed tempo, it is easy-peasy to overdub MIDI parts.

  4. Once I’m happy with the MIDI overdubs, I reactivate the tempo track, the audio will go back to its free-flowing tempo, and the MIDI will of course follow it.

Of course, if you don’t want tempo variations in the audio, you can stop at step 2 - the audio plays back as if it were recorded to a metronome.

Hope this is helpful!

Just updating this thread to provide a link to a related one, with a little more detail:

Cool thanks. I will post the result.

:ugeek: :sunglasses:

About ten minutes max to prepare a tempo track using “Merge tempo from tapping” is not a long time, probably take you 5 - 6 minutes when you’re used to it.
Preparation is always important and does take time in any craft whether music production or plumbing. There are, even in these days of wonderful computers, very few really magic bullets.

Later, once you have that tempo track in place, you’ll find it saves far more time than it took you to make it.
After all the best 4 minute songs are either done in an hour or can take weeks of production.

Cool thanks. Lets give it a whirl. :sunglasses: