What's wrong with the external tempo sync?

[ZooBooBooZoo]

Hi all,

I'm having a really hard time with the external tempo sync feature.
I have a set dedicated for playing along with Traktor. it's full of different tracks, loops, instruments etc.

Ableton is set to receive tempo through a dedicated internal midi port(LoopBe1 Midi) and when it's on the CPU load is almost double and the tempo itself is all over the place.

Because of this problem I started a new set to check what could go wrong. When I start a new blank set and add external tempo sync everything is fine. the tempo "modulates" only slightly (a few 0.1 BPMs here and there) and almost no additional CPU load.

Why is this happening? I noticed that if I take my Ableton and traktor set and turn off all instruments and FX the tempo stuttering is lessened but not back to it's pretty-stable original status.

I'm Using: Windows 7 64 bit, Traktor Pro 2, Ableton 9, LoopBe1 Midi Port, Massive, Reaktor, Guitar Rig, Sylenth 1, Kontakt.

[ZooBooBooZoo]

Don't tell me there's no hope at all

[doghouse]

I'll start by telling you something is wrong in your setup because Ableton's synch to MIDI clock is pretty good.

I'll take a wild stab here that you are tempo synching a lot of stuff in your set (instrument LFOs, FX parameters) and that processing is what is eating up the CPU.

Unless nothing else is on the MIDI port, clock msgs can jitter so all those small 0.1 bpm changes are being passed on everything in the set. Depending on how each device is coded, the overhead for dealing with clock changes might be large.

Maybe I have told you nothing you don't already know...

[Muzik 4 Machines]

ableton is a PITA with any sync(in or out) i really hope they remember people still use hardware in live10

[mikb]

Ableton is set to receive tempo through a dedicated internal midi port(LoopBe1 Midi) and when it's on the CPU load is almost double and the tempo itself is all over the place.
Why is this happening? I noticed that if I take my Ableton and traktor set and turn off all instruments and FX the tempo stuttering is lessened but not back to it's pretty-stable original status.

This is likely to be caused by a long standing bug in Live and external sync. Since 9.06 sync have been pretty good, but occasionally you may hit a set up that triggers it. 9.1 was pretty stable. I've had some issues with 9.1.1 and the 9.1.2 betas.

Personally, I have not noticed that the CPU usage of the song in question affect sensitivity to this. Please make bug reports of experiences like this one. I did and many others too I think, and since Ableton have made great progress on external sync in my experience.

[ZooBooBooZoo]

@doghouse: I'm not syncing so many stuff. most synths don't have any tempo-synced automation going on. Besides, the CPU usage is an understandable problem wheres the fluctuation of the tempo by dozens of BPMs is not.

I honestly can't understand why the CPU usage affects the external sync feature directly. the changing tempo might trouble the CPU but why is it happening vice versa?

[ark]

Do you mean that you're running Traktor and Live at the same time on the same computer? I would think that they would constantly be competing with each other for resources.

[ZooBooBooZoo]

Traktor doesn't require such an extensive amount of resources.
and again, that's beside the point. my main concern is the steadiness of the tempo and not the CPU usage. at least ATM

[deva]

ableton is a PITA with any sync(in or out) i really hope they remember people still use hardware in live10

It may be that the number of people using hardware is increasing...

[mikb]

Do you mean that you're running Traktor and Live at the same time on the same computer? I would think that they would constantly be competing with each other for resources.

If Traktor and Live can play the projects to be used without sync and the resources are sufficient, then adding external sync to Live shouldn't increase CPU usage so much as it usually does.

[ZooBooBooZoo]

Either there's something about the technology I don't understand or this is a serious bug.

Again, I might be missing something, but this seems like a fairly simple task and I don't get why the fluctuation of the tempo is so sensitive.

[mikb]

Either there's something about the technology I don't understand or this is a serious bug.

Again, I might be missing something, but this seems like a fairly simple task and I don't get why the fluctuation of the tempo is so sensitive.

Considering the MIDI sync protocol is so old it should be a minor factor in the real-time tasks Live has to tend to. Perhaps there's more to it than that but it really shouldn't be.

You could sign up to the beta program and download the latest beta and then make a bug report on this important issue.