Incoming MIDI Clock and slight tempo changes

J

jcalama

Member
Good evening everyone,

My FM3 is receiving midi clock info from Ableton Live via 5 pin midi out from my Focusrite Scarlett 6i6 into the midi in of the FM3.

Even though the tempo from Ableton doesn’t change, the FM3 registers slight tempo changes which cause things like tempo-synced delays to sound warbly and jittery.

What if anything can be done about this?

Thanks in advance!
 
jcalama said:
Good evening everyone,

My FM3 is receiving midi clock info from Ableton Live via 5 pin midi out from my Focusrite Scarlett 6i6 into the midi in of the FM3.
Click to expand...
Help me understand. Your FM3 is receiving MIDI clock from Ableton and from your Scarlett? Sounds like a conflict. :)
 
Rex said:
Help me understand. Your FM3 is receiving MIDI clock from Ableton and from your Scarlett? Sounds like a conflict. :)
Click to expand...

It's not receiving from both. My FM3 is connected to the Scarlett by 5 pin midi. Ableton transmits midi clock.
 
jcalama said:
It's not receiving from both. My FM3 is connected to the Scarlett by 5 pin midi. Ableton transmits midi clock.
Click to expand...
So Ableton transmits MIDI clock to the Scarlett, which passes it through to your FM3?
 
jcalama said:
Good evening everyone,

My FM3 is receiving midi clock info from Ableton Live via 5 pin midi out from my Focusrite Scarlett 6i6 into the midi in of the FM3.

Even though the tempo from Ableton doesn’t change, the FM3 registers slight tempo changes which cause things like tempo-synced delays to sound warbly and jittery.

What if anything can be done about this?

Thanks in advance!
Click to expand...

Midi clock is not a precise protocol, so slight jitter is to be expected when trying to derive a bpm from it. This has come up before and there’s not a lot that can be done. It’s a trade off between keeping a constant tempo and being responsive to tempo changes. How much jitter are you seeing?
 
  • Like
Reactions: Rex
I have a MC6 that I use as a clock source for another modeler with no problems. As an experiment I slaved the FM3 to its clock this morning and the long and short of it is I see no jitter which tells me the source of the jitter lies elsewhere.

Non-RTOS multitasking OS’s aren’t designed to meet scheduling deadlines and will of necessity introduce timing irregularities - there are a multitude of scenarios the scheduling algorithms can be optimized for but deadline consistency isn’t one of them.

The other thing that could introduce latency issues is the fact that the interface between the Focusrite Scarlett 6i6 and the computer is USB. The USB protocol has its own scheduling algorithms which may well exacerbate the problem.
 
jcalama said:
Good evening everyone,

My FM3 is receiving midi clock info from Ableton Live via 5 pin midi out from my Focusrite Scarlett 6i6 into the midi in of the FM3.

Even though the tempo from Ableton doesn’t change, the FM3 registers slight tempo changes which cause things like tempo-synced delays to sound warbly and jittery.

What if anything can be done about this?

Thanks in advance!
Click to expand...

I only have my AxeFX II with me this week, but I'm not seeing any measurable jitter in delay times when getting clock from Live 10.1.30 at a fixed tempo. (MacOS 10.14, AxeFX II connected via USB.).
 
yeah, i would check the cable lengths and if you can, connect the computer directly to the axe via usb. i'm doing the same and there's no jitter at all. however, if i send clock from my morningstar and route it to the axe via the laptop, it's all over the place.
 
GlennO said:
Midi clock is not a precise protocol, so slight jitter is to be expected when trying to derive a bpm from it. This has come up before and there’s not a lot that can be done. It’s a trade off between keeping a constant tempo and being responsive to tempo changes. How much jitter are you seeing?
Click to expand...
Not much, 10ms in either direction, enough to warble delays...
 
jcalama said:
Not much, 10ms in either direction, enough to warble delays...
Click to expand...
That's more than you should be seeing. I'd be surprised if the problem is the precision of the clock that Live is sending. You could try an inexpensive USB to MIDI cable instead of going through your Scarlett.
 
HEllo,
i’m writting to you to ask about any known issues with the FM3 and midi thru. My current setup requires that the (ABLETON)clock be sent to the FM3 and then out to the H9 for clock sync and program changes. The Tempo is fine the FM3and later but the H9 has constant fluctuactions(jitter) and cant settle down or very rarely. Odd thing is when im on the tempo page on the FM3 it seems to be better but as soon as i exit the menu , there it goes… I’ve tried the H9 direct out of the Iconnect midi box and it works fine.
I’ve looked in the menus but haven’t found anything that could help. any suggestions?
 
You must log in or register to reply here.
Back
Top Bottom