Pianoteq STILL Creates SLOW MIDI Files

So the first question is how long does the piece actually take to play ?

What you're doing is comparing iMovie's video timing with Pianoteq's audio timing.  The problem is that you've no actual timing of the piece independent of those to use as an absolute reference.

You need to establish a proper baseline measurement with a reliable stopwatch.  Don't rely on video timing to be right.  I'd go the other way - assume it's wrong, as it's the source of much grieve for many people.  Transcoding can also introduce of issues like this.

I'd also consider trying a different video editor.  Maybe Da Vinci Resolve which has a free version.

I second the theory that it's an issue with NTSC Drop Frame.

Hmmm... OK... I did some tests and yes I agree that there's a real thing: Pianoteq "Export to audio file" renders ever so slightly slow! It's losing about 20ms per minute here, same as what you are reporting.

I would guess (though I would no longer *bet*) that the majority of Jordan's drift is still down to 29.97 fps video being treated as 30.00 fps. But the discrepancy you are talking about: Yes, it's real. I'm looking at it right now.

My Test:
1. Generate a MIDI file that's just one note being played *exactly* once per second for a couple of minutes
2. Load it into pianoteq
3. Export to audio file
4. Look at the audio file

Not sure if this is related to your problem but this article mentions issues related to different clocks being used by software and hardware in relation to MIDI, ASIO, etc..

Here's one section that caught my eye from that article :

I do remember some time ago one video I made was slightly out of sync towards the end. Unlike my other videos, I had done some editing to the Pianoteq midi file using Midi Editor before rendering it and then syncing the audio in my video editing software.

My conclusion at the time was that the metronome in Pianoteq was (slightly) different to the Midi Editor metronome setting, I would not have changed this and to my knowledge would be the default 120 bpm but possibly some other tempo in Pianoteq.

This is the only time my videos had a sync issue. If in your case you have edited the midi file in some other software, then it might be worth checking Pianteq metronome settings and the midi editor metronome settings are both the same, both at 128bpm for example. Also even if the metronome sound is off, it is still active in the midi file.

I faced the same problem. I recorded video on Android at a speed of 60 frames per second. I was processing a video on Mac in Davinci. The sound was exported from Pianoteq from Ableton with different sampling rates - 44100, 48000 and 96000. When I added the soundtrack to Davinci, the tracks became different in length. The difference was small, but still! I tried editing the video in Final Cut and now I don’t notice any problems with the desync.

Looking through the information about the media object in the VLC-player, I noticed that the frame rate was something around 60.00367 per second.  And these decimal places were different for different videos.  Apparently video editors interpret the number and duration of frames differently.  And apparently with sound files a similar situation.

I have just made an hour long video to test my line recording. The video stayed 100% in sync throughout, after trimming and rendering still 100% in. Although I setup my camera and mixer to enable this some time ago, I payed no real attention to sync, I just thought it must be more lined up, and never thought that my old method of using rendered midi files were actually running slow!

It seems unless one can match 100% with the midi file, then the result will be as if the audio is from an entirely different source (and time) from the video performance. I'm able to achieve this without going to the trouble of rendering and syncing. I would recommend line recording over syncing rendered midi files, and I can't see (or hear) any benefit now for ever doing so again.

Thanks for the clear explanation!

Good catch, xooorx, this is fixed in Pianoteq 6.7.1 !

The problem is still there in version 6.7.1.

I used a digital stopwatch to time myself playing for exactly 10 minutes, and when I timed the playback from Pianoteq (without exporting to audio) I got an increase of 1 second. (Actual numbers: live playing: 9:59.96, playback: 10:01.00)

I made a video test which became gradually out of sync like before, and another test using Pianoteq as a VST in Garageband, which had no problems, stayed in sync, and passed my stopwatch test.

I appreciate the attention this issue is getting.

-Jordan

bump - original post updated at top

Are you sure both MIDI files have exactly the same tempo ? I can't reproduce that , I have recorded a very long midi sequence simultaneaously in Pianoteq 6.7.3, Garageband and Reaper, for 34 minutes, and they all are perfectly in sync when I import the Reaper and Pianoteq midi files in Garageband, and also when I import the wav file generated from Pianoteq in garageband.

Time code works when you chain two devices together while recording, but typically only professional gear can input/output time code.

I've recorded fairly long video along with Pianoteq without drift issues... but not 3 hours. Camera drift is VERY likely to happen after 3 hours, although 6 minutes is still huge. If everything else is correct I would suspect a sampling rate issue there (something other than 48 kHz). If you get your frame rate messed up in any way within your video editor you will get significant drift too.

Julien's idea would definitely be worth checking, I've accidentally bumped tempo without realizing it until trying to match exported audio to a video track. One second off in 10 minutes is quite a lot.

Have you tried to run any tests with 5-pin MIDI DIN connectors along with a USB connection?  On macOS an older type serial connection might present more options to you than a newer USB one by itself does.

With my YAMAHA DIGITAL PIANO P-95 connected via 5-pin MIDI DIN connectors plugged directly into a MOTU Micro Lite (USB MIDI interface) I've got some which immediately I can check off the Yamaha Keyboard Properties window inside MIDI Studio of the Audio MIDI Setup on macOS.  They seem unavailable to direct MIDI device to computer connections made over only an attached USB cable alone.

MIDI Beat Clock and MIDI Time Code are additions available as properties I can check off that the keyboard transmits and receives, while General MIDI and MIDI Machine Control I can check off also but as features of the MIDI device whenever connected through 5-pin MIDI DIN connections.

Each of the designations show under Transmits and Features and has a check box so long as I'm making the adequate connections on MIDI serial cables with their MIDI DIN connectors.

I’m saying this to say that MIDI Beat Clock and MIDI Time Code, both available to anyone using 5-pin MIDI DIN connectors, also might alleviate some of the MIDI timing problems you experience.