im getting drift on all the midi outs. its a range of .3 bpm. for example, if i set the bpm to 120, other devices will read it as 119.9/120.1. its causing sync issues with other devices.
Its not because other devices read it as such that it means it is fluctuating like that.
How is it causing issues?
I can say from personal experience the clock is spot on and does not cause any issues in my setup
Same here. The Sync is tight even if my gear hooked to the hapax shows 0.1, 0.2 or 0.3 BPM drifts.
Yeah, I’d bet its not the hapax causing drift. I run every channel out of mine and its perfect all the time. The fluctuation you see is normally the device showing the bpm working it out wrong 
if it updates frequently its likely to show more minor bpm errors.
If you can, run metronomes on the devices that seem to wander and use the hapax’s midi compensation to correct it. I have a tr8-s that always needs a little tweak so it hits right. Its usually the slave device rather than the Hapax. It can get a little funky if you have usb hooked up to a pc and you launch Ableton or something while its playing. Hitting stop and start will get it all back in sync.
running it through befaco midithing v2, show midi pc, and ios. all get a .3 drift. running other devices such as the midronome yields no drift on these monitors. devices are going out of sync / out of phase with the hapax.
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This is basically impossible, unless you have a dodgy cable somewhere that causes Midi clock bytes to get corrupted/go missing.
Midi clock is just a steady train of clock bytes. The clock slaves follow these clock bytes one by one. Which means if you have a terrible master clock that pushes the bytes back and forth, the slave devices will follow that terrible master clock EXACTLY the same.
So a gradual drift of certain devices is technically impossible.
As for visual display, that’s just the wonky world of floating point math. You should really not deduct any “drift” diagnose based on that.
you just said something was impossible and then explained how it is possible…
like i said its only with the hapax. everything else has a steady clock.
i reduced the drift to .1 by sending clock over midi A and everything else over midi B. i suspect the majority of the problem was because midi sends data over one lane, and there was just too much data transmitting at the same time to get steady clock messages. though there is still a slight drift.
Drift can’t be anything other than the receiving end afaik. If your clock is wonky, the slaves will just follow the wonky clock like @rv0 said.
Keep in mind you are trying to sync 2 computers doing a ton of other things besides trying to follow the clock…
You are sending both clock and transport right?
sorry it is a language misunderstanding, English is not my native language.
What I meant to say is that it is not possible for some devices to get behind, and others not to get behind. All devices should behave the same (unless there’s problems in specific places of your midi chain, e.g. long daisy chain, bad splitter devices, etc)
flooding of the midi bus with other data could of course also be a cause, but you didn’t mention any of that in your first posts
Midi clock messages are priority messages according to the midi standard. So either you really had a lot (and I mean a lot) of other data going over it, or some of the devices in your chain arent handling that amount of data well or are not properly following the standard and giving priority to other things.
Best is to simplify your chain and troubleshoot by adding devices one by one, perhaps also already doable with mute/unmute.
This is not a valid method to measure drift.
There’s some midi tools that can do it (MidiGAL being one of them)
But you can sort of do it with a PC… Take a midi monitoring app that can export the data with decimal timestamp to csv, record incoming midi messages, export into Microsoft Excel or Google Sheets and calculate the timestamp deltas
only clock over A and all transport over B got it down to .1 drift.
But what does drift mean? That the clock fluctuates / is unstable by .1 bpm?
If so, that shouldn’t matter, clock slaves will just fluctuate themselves by .1 bpm cause they follow the master clock.
i was not sending an excess amount of data, but separating them over the 2 midi outs helped nonetheless. like i said, i used multiple midi monitors and got the same result from all. currently im using the befaco midi thing v2 cause it has decimal points to the hundredths and seems to be the most accurate.
yes perhaps drift is the wrong word. fluctuates in a range of .1 or .2 every second. the hapax is the master.
i dont understand why everyone is saying the master cant fluctuate. cant it easily be a problem with the cpu or the coding?
yes, it has a midi monitoring feature, but that’s not what i meant, no way to get the data in a spreadsheet, and no way to measure clock accuracy/drift/jitter
It’s just a thing that converts midi to CV that happens to have a tempo readout
because your diagnose method is not scientific. You look at a BPM screen and deduct that things are wrong based on that.
Slave devices can show a tempo deviation even with the tightest clocks. What is 120BPM for one device might be 120.1 for another device. That’s why we send clock and not just start/stop.
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Ok so when there’s drift, the master and slaves will go out of sync over time.
Still a fluctuating master is fine cause the slaves will just follow the 24 pulses per quarter note…
Some devices are just better at following than others. My Octratrack follows the Hapax just fine, my MPC Live for instance doesn’t handle being slaved at all. Why? Probably because the MPC is just an Arm based computer doing a shitload of other stuff besides being a MPC. It handles network, a colourful screen etc AND needs to follow the clock. When I make the MPC master all other devices will just follow its wonky clock even if it fluctuates a couple of bpm.
scientific method… sir nothing i use as a master clock shows fluctuations except for my hapax. my gear works fine, except when used with the hapax. the midi monitors dont show any fluctuations for anything other than the hapax. so the conclusion? my hapax has fluctuation problems.
interesting. but my gear works fine with other master clocks.
Then slave the Hapax…
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