pattern sync start delay

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derb
 
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pattern sync start delay

Post by derb »

Hi!

I got strange problem with my xoxbox when I want to use it in pattern/track midi sync. After pressing "play" in Ableton Live xox starts after about 200ms delay.
When i use midi play without xox internal sequencer everythings works good, latency is normal.
I tried to switch between some firmwares but without good results.
Is there any chance to get i work as it should do?

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antto
 
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Re: pattern sync start delay

Post by antto »

try the following
set the DAW to 150BPM
play it, and record the audio
turn the BPM down to something low, like 30

then, on the recording, measure the latency
don't use the very first note after the start, since that one is likely to be delayed a bit more then the following, due to sequencer resetting, and retrigger circuit not warmed up yet
then, measure the latency again on the part with the slow tempo

if the latency is the same (more or less) - then this is really just latency
if on the slow part the latency gets that many times bigger - then there's a missed clock tick (or two..)

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derb
 
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Re: pattern sync start delay

Post by derb »

Thanks for reply

150 BPM - 32ms
30 BPM - 102 ms

Is it caused by xox or DAW?

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antto
 
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Re: pattern sync start delay

Post by antto »

so, it's a clock desync then, not just latency
it could be either one of them, or both

do you know what firmware you have currently on the x0x?

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derb
 
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Re: pattern sync start delay

Post by derb »

Maros 1.4.1
Previous was Sokkos 2.0, same problem

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antto
 
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Re: pattern sync start delay

Post by antto »

you could try to see if it's the DAW, by loading a MidiMonitor plugin (one which timestamps the messages)
but it might not work, since the DAW may only send the midisync out to the interface, but not to the plugins
in that case, an external midi monitor/analyzer app like MIDI-OX
you'll need to use one of those virtual midi port apps, set the DAW to output to the virtual port, and then hook MIDI-OX to listen on its other end

for the actual testing - use a slow tempo, the slower - the better
press play, let one or two notes pass and press stop
then check the midi data (or make a screenshot)
you should see a MIDI_START message, followed by MIDI_CLOCK messages
the midi specification says that the machines should not start on the actual MIDI_START message, but only on the following MIDI_CLOCK message
it's possible that the DAW fails to follow the specification and sends a MIDI_START and starts playing, and then sends a MIDI_CLOCKs from the 2nd tick onwards

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derb
 
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Re: pattern sync start delay

Post by derb »


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antto
 
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Re: pattern sync start delay

Post by antto »

well, weird..
the timestamp doesn't show a big delay between the MIDI_START and first MIDI_CLOCK
i looked thru sokkos2's code and i really think it's okay

if you play/stop the DAW a few times - is the x0x late every single time, or is it random? is it late from the start, or does it follow at first?

you could try slaving the x0x to another MIDI master, say, a hardware drum machine or groovebox, anything that generates midisync and is "respectful"
see if the x0x is late then, and if it's not - it must be the DAW's fault

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derb
 
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Re: pattern sync start delay

Post by derb »

Weird....

I think I have to switch to another DAW. I loaded a busy project - xox delayed as hell. Then I opened new - perfect sync...

Thank you antto for your time and help :)

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