Ableton Tempo Change, when it takes effect?

bbulkow

I'm on V47 and using very simple workflows. It's been a while since my last looping with mobius, so just dropped the new version.

I'm running as an ableton-hosted VST, I have track 1 with the sync source set to 'host' and my recording set to 'sync bar' and quantize set to 'sync bar'.

When I first launch ableton (and thus mobius), everything's sync'ed up. The usual (basic and good) pattern: I hit record, the loop waits until the beginning of the next bar, starts recording, and when I stop recording, I get the expected wait and the recording syncs to the bar.

After doing some looping, I often want to change it up. I reset all my loops (nothing recorded nothing running), change the ableton tempo, then go back to my first (leader), and attempt to record.

What I find is the quantization is not right. It does "synchronizing" and wait, but then it starts recording somewhere in the middle of the bar. The new length is right, so I know mobius has picked up the tempo correctly. It seems like its come unglued from the bar and beat.

I've tried restart on my leader, and global reset, and restart with restart set to 'content and parameters'.
I've tried starting and stopping ableton's transport between tempo changes
I've tried setting the sync record unit from bar to none, save, back to bar, save.

sometimes the recording bar sync is right. Which makes me think there's some magic, but when I go through one at a time, no UX pattern works reliably.

The recording length is always accurate.

Restarting ableton seems to work.

Suggestions?

bbulkow

Having fogged around with this for more than a few hours, I think the reliable path is:

Have no loops running, no leader / master
In ableton (with the click going to judge feel), change the tempo.
Stop the ableton transport, set the arrangement position to 1.1.1 (second press of stop), start playback
Go back to mobius, use the new tempo

I have not yet found a case where this didn't work - but I also changed a few other settings around things like making sure "late start adjustement" was off....

alexs1

I experience something similar when I try to change the tempo of the host after transport starts (in FL). While the BPM looks like it's being read right, the pie doesn't seem to "get with" the new tempo.

The main question is whether the new loops only look like they're not quantized, or if you record only by ear, does the loop audibly start and stop on time? I've had that happen too, where the visual circle just looks off but somehow the audio is still where it should be. If it's both, then yeah, might be a bug with how Mobius tracks tempo changes in Host Sync.

bbulkow

I just wanted to say I've still got this going on. It seems like after a tempo change, some combination of Mobius "Global REset", "restart", and a host transport stop/start will cause good things to happen.

I don't ever expect a tempo change in flight - with recorded loops - to do something snazzy (although maybe they would, warp and all), but I do kinda need a way to reset tempo that's predictable. Halp!