Midi tempo/map Grid to match audio feel LP7

[jchas]

Originally Posted by pro

Need help! Can't get my head around making a midi grid to match the 'feel' of a player. I use Logic Pro?

Don't know if i'll be much help - but I do this a lot in Cakewalk. Start with getting tempo as close as possible, If beginning of song is pretty static start with that, if not shoot for a chorus section which is typically a little more upbeat. If Logic has a 'snap to grid' button turn it off. Record a MIDI click track - depending on the music you're working around a 1/4-note high hat (f#3) usually works best though sometimes a kick (C3), snare (D3) might work better. Slide audio tracks to start on downbeat of measure 3, this allows you room to leave a click-in. Zoom in close (usually with-in 2-3bpm) so your tempo draws will be gradual. Fine tune tempo to align with songs intro. As soon as you notice the smallest drift back up a measure and start a 1-measure exponential curve up or down, moving about .5bpm. Check for timing adjust as necessary. Most transitions from verse to chorus are within a 1-2 bpm range, though of course, anything is possible. Repeat as needed.
For ******s you will need to zoom way out. Exponential curves still work best but i've had to drop as much as 60-70bmp and try many attempts to get it right.
I've also found it's easier to get it 'close' on the first run through the song and tighten it up on the next 3 or 4 passes. Hope this helps

Oh yeah, and it helps to e.q. the audio to make it easier to 'lock-in' on something. If you have drum tracks (and he's got a good internal clock) the high-hat works pretty well.

[Orren]

Originally Posted by pro

Need help! Can't get my head around making a midi grid to match the 'feel' of a player. I use Logic Pro?

I have good news and bad news.

The good news is--you can relatively easily make a MIDI tempo map to match the feel of an audio track in Logic Pro 7. What you want is the feature known as the "Beat Mapping" track. This is one of the Global Tracks. You can activate it in the local View menu of the Arrange window.

You'll want to read the manual (or if you own my book Logic Pro 7 Power, it's in Chapter 5 ) for the full details on how to use the Beat Mapping track. But the basic concept is simple, and works like this:

1) Activate the Global Tracks and its Beat Mapping track in the View local menu of the Arrange. You will have an empty track above your Arrange tracks.

2) Select the audio file with the "feel" you want to create a MIDI tempo grid from.

3) Drag the file onto the Beat Mapping track. Logic will then analyze the file and detect its transients, creating one tempo event on the Beat Mapping track for each transient detected. The result will be a Beat Mapping track filled with thin white lines representing tempo change events based on the analysis of your audio file.

4) In the Beat Mapping track, you can then move, add, and delete tempo events graphically to more precisely match the newly created MIDI tempo change grid to the audio.

And that should reclock your MIDI tempo to your audio!

Ok, the bad news: how effective the Beat Mapping track is will depend on your audio track. The more pronounced and obvious its transient beats, the better the mapping will be, and the less "clean up" you'll have to do. If you use a relatively clean and sparce freeform drum track, for example, you'll get great results. But if you are feeding it a very washy and wet synth line...well...good luck.

Here are two quick tips to get you going:
1) Have it analyze a region that begins at the start of your song. You technically *can* use any region but I find if you start at the beginning, the results are better.

2) The Beat Mapping analysis function works on MIDI as well as audio. So if you're trying to map an audio file that is particularly difficult, you can often get precise results by creating a MIDI "guide track"--in other words, if you're trying to beat map a very complicated piano line that isn't working, record another MIDI track using for example a cowbell, and just tap all the quarter-note beats along with the piano part. Then have Logic beat map the MIDI guide track. That should work well.

Hope that gets you started!

Orren