Last multiple pulses missing in sync file

Any questions about the Software Tools (FirmwareUpdater, SyncFileGenerator, ErrorLogExtractor)
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Claid
Posts: 3
Joined: 26 Apr 2023, 22:35

Last multiple pulses missing in sync file

Post by Claid »

Operating System and version: MacOS 12.5.1

Short description of the issue: When generating a sync file, multiple pulses at the end of the file are missing - not sure if this is important or not

Steps to Reproduce: Open Sync File Generator and generate a 4 bar file at 120 bpm and 4/4 time at 48kHz. Drop file into DAW and view the waveform. loads of the pulses at the end of the file are missing.

Expected Behavior: I assume for the sake of keeping a stable clock, the pulses should last until the end of the file.

Actual Behavior: Multiple pulses at the end of the file are missing.

Unsure if this is intended effect, but I fail to see how as this surely could be good for the sync. I have tried syncing the Midronome to Ableton Live 11, following the instructions from 09:17 of the video manual (https://www.youtube.com/watch?v=hkw9dmL ... =Midronome) as well as the actual manual (https://files.midronome.com/docs/midron ... -guide.pdf)
Simon
Posts: 790
Joined: 09 Jan 2022, 22:08

Re: Last multiple pulses missing in sync file

Post by Simon »

Hi :)
This is normal. Can you get the sync to work?
Simon
Claid
Posts: 3
Joined: 26 Apr 2023, 22:35

Re: Last multiple pulses missing in sync file

Post by Claid »

Hi Simon, thanks for the quick reply!

I have managed to get Ableton Live to send the audio file generated by the tool to the Midronome and the Midronome is hearing it at a good volume and matching with its own metronome - however the are not in sync and it goes completely out of sync when the audio file stops playing, which is has to do as the clip has Warp disabled, and Warp needs to be enabled in Live in order for Loop to be enabled.

I have made a video - let me know where I can send this so you can see, as it is difficult to explain complicated issues over text. 🙂

EDIT: I believe this is due to audio lag within Ableton Live and not the Midronome! I will test and let you know - apologies in advance if this is the case. :)

Question - my analysis leads me to suspect there are 24 pulses within each bar, is this correct?
Simon
Posts: 790
Joined: 09 Jan 2022, 22:08

Re: Last multiple pulses missing in sync file

Post by Simon »

Hi Claid,

Yes, 24 pulses per beat, just like MIDI Clock.
it goes completely out of sync when the audio file stops playing
Yes that makes sense, the Midronome can only stay in sync when the DAW is playing (and the sync track is sent to it).

Make sure the WAV file generated by the tool is at the beginning of the section, is not warped, and check the volume as explained in the Midronome Manual (by going to the settings -> inP -> select Syn and stay there, then check the LED's while the DAW is playing).

Regarding the video - I think this easiest is to upload it to Google Drive, Youtube, or on the VIP facebook group ( https://www.facebook.com/groups/midronomevip )?

Cheers
Simon

PS: since this is not a bug, I moved it to the "Questions" forum.
Claid
Posts: 3
Joined: 26 Apr 2023, 22:35

Re: Last multiple pulses missing in sync file

Post by Claid »

Thanks Simon, much appreciated. :)

After much testing this afternoon I can confirm that the timing is rock solid - MOST of the time.

Say I record four bars of the Midronome's output for analysis - three of those bars will be super tight, and one bar will be off by around 18-20ms.

Also, one thing to bear in mind is, as you say, the audio file from Live has to be consistently sent to the Midronome for it to remain in sync, however, you also advise to turn off Warp for the clip, which means that Loop will also be turned off, meaning the audio file will play only once then stop. This is how Ableton Live works. However, I have a workaround - I Warp the audio clip, set the BPM of the clip to exactly what it needs to be and set the Clip Length to be however many bars I created the audio file. Voila - a perfectly looping audio file. That said, the same issue occurs with this method as explained above - one out of every four bars is always out of time by around 18-20ms.
jmct
Posts: 1
Joined: 28 Apr 2023, 00:38

Re: Last multiple pulses missing in sync file

Post by jmct »

••one out of every four bars is always out of time by around 18-20ms.••

I second this. 3 out of 4 bars will be synced to grid as expected but there is still drift.. I expected the sync to be rock solid to the Ableton live grid?

I've only spent about an hour on this so I'm sure its something I'm not doing right.

Cheers
Simon
Posts: 790
Joined: 09 Jan 2022, 22:08

Re: Last multiple pulses missing in sync file

Post by Simon »

Very interesting feedback guys, thanks. I am not much an Ableton user (I actually only ever used it to test the Midronome), and the other DAWs I regularly use (Pro Tools and Studio One) can just loop over any selected time, warping or not. Are you saying in Ableton it is not possible to loop a track if warp is disabled?

As for the sync issues, what I can guarantee you, is that the Midronome is very much tightly in sync with the audio sync signal. An easy way to verify this is by syncing two Midronomes, since it uses the same sync signal (except that it's generated by a Midronome and not played from a DAW). The problem is that the audio sync signal needs to be sent exactly like it was generated by the Sync File Generator tool, and I've often seen DAWs who decide to send something else than what's written in the files, especially when modifying the audio like warping.

But 20ms sounds like it is exactly 1 clock tick (one pulse) late, so my guess is somehow there is one of the pulses which should be sent and is not (probably just when the looping happens). Note that the file generated by the tool is on purpose missing ticks at the beginning, so it cannot be used for looping (or you have to loop only a part of the file).

We'll test the looping in Ableton and try to improve the Sync File Generator so it works better - keep the feedback going ;)

Cheers
Simon
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