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John_Toolbox
02-23-2011, 10:41 AM
Does anyone know what the ppq(pulses per quarter note) resolution of a MIDI file exported from pro tools will be saved at? Can't seem to find anything on this.

DonaldM
02-23-2011, 10:57 AM
Wouldn't it be the standard 480? I can't imagine that PT would change that to some other value, as 480 is the standard (or rather 24 ppq is, but most professional midi sequencers go 20 times that, hence the 480.) I don't have the PT manual where I am right now, but I'm surprised if that info isn't given on a graph or chart somewhere in it.

flommer
02-23-2011, 11:48 AM
For some reason the number 960 jumped into my head, but I'm not sure from where..

John_Toolbox
02-23-2011, 11:58 AM
I know that internally, pro tools is 960,000 ppq, and the grid resolution for midi is 960.

What I've found with a lot of apps is that the internal resolution is different than the one they export to. Logic is 960 internally, but exports to 480.

I am assuming pro tools exports to 480, just haven't been able to find anything in writing that confirms this.

DonaldM
02-23-2011, 01:35 PM
Logically you would think it is 480 because it would have to export to a standard midi file and thus meet the conventional midi standards and that would be importable to another program or midi device.
If that weren't the case, then exported midi files from Pro Tools wouldn't be much use on another system. So, my assumption would be 480 ppq unless proven otherwise.

John_Toolbox
02-23-2011, 02:18 PM
480 is the most common, but by no means a standard.

Here's what I've found so far:

Logic - 480
DP - 480
Cubase - defaults to 480, but adjustable
Sibelius - defaults to 256, but adjustable from 96 to 960
Finale - 1024
Ableton Live - 96

Note that these are for exported MIDI files only, almost all of these programs run at a different internal resolution. I'm not sure if all of these numbers are 100% accurate, some of them were found on forum posts, not in manuals.

I'm really surprised at how difficult it is to find this information. I have a way to figure this out, but thought that searching the internet would be faster. Guess I was wrong. If no one confirms this I will post my findings here after I run some tests.

DonaldM
02-24-2011, 11:50 AM
You're right...the standard isn't 480, but it is, as I understand it 24. Most DAWs use 20 times that, hence the 480. If you do find out what PT exports to, please let us know. I've always assumed 480ppq as it is so common an is, for most purposes a de facto standard even if not THE standard.

John_Toolbox
02-26-2011, 06:11 PM
Well so far it looks like it's exporting at least 960ppq. Exporting a file with a note starting on each tick and re-importing it does not re-arrange the notes.

DonaldM
03-01-2011, 07:26 AM
Hmmm...that is interesting.

John_Toolbox
03-01-2011, 10:38 AM
I verified this with Logic too(Logic operates at 960ppq internally, and apparently imports at it as well, despite only exporting at 480ppq)

I just ran another test, both doubling and quadrupling the amount of notes in the same space(effectively 3840 ppq). Pro Tools still re-imports the MIDI file with these high resolution notes intact. This means that Pro Tools exports MIDI files at a very high ppq resolution(probably the same resolution as the sample rate you are using), and also that Pro Tools does not affect the ppq resolution of an imported MIDI file at all. I have a feeling that this will be the case all the way up to the sample rate. When opening the file in Logic, the notes are forced to the next tick for 960ppq(so the first 4 notes are all "snapped" to the first tick, the next 4 notes "snapped" to the second tick, etc.)

John_Toolbox
03-01-2011, 10:57 AM
Okay, it's not quite sample accurate at 48Khz, but it's close. Here's a before and after of MIDI exported and then reimported with a note on every sample:

http://pic100.picturetrail.com/VOL1039/1351418/15224248/395468798.jpg

It appears that PT rounds MIDI notes that are at the sample level somewhat, basically if there are 10 notes in a 10 sample space, it rounds them to be 4 notes, either 3 samples or 2 samples long.

John_Toolbox
03-01-2011, 12:50 PM
Yet another interesting variable: sample rate....

I re-saved the session at 192Khz. So now the notes are 4 samples long. Re-importing the midi file saved from a 192KHz sessions was rounded differently this way(lengths are divided evenly, instead of 3 samples, then 2 samples), as you can see from the screenshot:

http://pic100.picturetrail.com/VOL1039/1351418/15224248/395470379.jpg

John_Toolbox
03-01-2011, 08:23 PM
Well for anyone that's curious, Pro Tools exports MIDI files at 9600 ppq.

DonaldM
03-02-2011, 06:44 AM
Good to know, I guess. But I am a bit surprised...I just assumed 480. Oh well..what do I know???:eek:

flommer
03-02-2011, 11:11 AM
Good to know, I guess. But I am a bit surprised...I just assumed 480. Oh well..what do I know???:eek:

I don't know what's worse: Being wrong or being right and not having any idea why....:confused:
:D

John_Toolbox
03-02-2011, 11:15 AM
I never would have guessed it was more than 960. What I don't understand about it is that there is no other program I'm aware of that runs at 9600ppq. So this is a completely non-standard resolution that also differs from the internal resolution of pro tools itself. There should really be a way to set the export resolution to a more logical ppq value.

DonaldM
03-03-2011, 06:13 AM
I never would have guessed it was more than 960. What I don't understand about it is that there is no other program I'm aware of that runs at 9600ppq. So this is a completely non-standard resolution that also differs from the internal resolution of pro tools itself. There should really be a way to set the export resolution to a more logical ppq value.

Yeah, you would think. It does seem a bit odd...and bit of overkill, if you ask me. I agree though, the user ought to be able to select the output resolution. Maybe you should toss that into the suggestion box at Avid? ;)