Gate in and sequencer...

[charloctave]

Does anybody have an idea of how the MxB sequencer reacts when you send gate signals to it? I can hear something reacting but can(t figure what !
AND : is there a way to make the sequencer run step by step at each gate signal?

[DrJustice]

If you want to run the sequencer step by step from a gate or clock signal, use the Sync input and set the "Sync Clock In/Out Settings" to 1pps (1 pulse per step) - ref. manual 7.2. MIDI Control Center settings and 7.3. Settings mode.

Edit: The  "MIDI clock source" need to be set to Sync, and the MIDI  SYnc button must be enabled as usual for external sync.

[charloctave]

Thank you Doc! ....but it doesn't work! Would you mind to check my setup, please?

[charloctave]

Thank you Doc! ....but it doesn't work! Would you mind to check my setup, please?

[DrJustice]

That looks right. As a sanity check, I just hooked up my MicroFreak as the sync source, setting it to send 1 pulse per step and it worked as expected.

What is your sync source? If it's indeed a (note) trigger, make sure it's a V-trigger and not an S-trigger. The former is the most widespread, and the second is mostly found on vintage gear. Even if you have a V-trigger it could be inverted on some quirky pieces of gear - if so, check and see if there a switch or menu item to invert it.

The expected signal on the Clock jack on the MatrixBrute is a positive 5V pulse. This is what you get from most keyboard gates and clock sources.

[charloctave]

Hum! the signal sent comes from the gate out of a Moog etherwave theremin. I have no idea if it's an S or V, and don't even know what that means. All I know is that it triggers perfectly notes of the MxB. When I run a sequence of the MxB, but with the seq sync off, it runs normally when the gate signal is off, and when it's on, the sequence keeps on running without the attacks of the notes, just as if the  amp envelop stays on sustain.
Anyway, I'll ask theremin specialists if the trigger is S or V.
Thanks again, Doc!

[charloctave]

The answer came quickly from the thereminists' community : it's a V trigger, delivering 0 volt when off, 10 volts when on...

[DrJustice]

OK... I read over here that you have made a cable with a voltage divider for this purpose - good move as we want the 10V down to 5V. Oh and a very cool video there too! :-)

I suppose you made it a 2:1 voltage divider, in which case you should have a good signal. I just did another experiment to check if there are any Start signal required - the 3.5mm TRS Sync jack has both the clock and a run/stop signal AFAIK. I did this by just connecting the Gate output of the MicroFreak Gate Out to the Sync In jack on the MxB.

That works, as in I can trigger the MxB sequencer from the MicroFreak keyboard. However, there's a quirk: the MxB uses the incoming gate pulses to determine a tempo (you can see it on the MxB tempo display), and the note lengths are determined by the derived tempo. If you play a steady tempo, it works pretty well, but if you vary the tempo you may get unexpected note trigger points and lengths. And, the last note that you play will be long as it "waits" for another clock pulse to keep that tempo derivation going. This could be improved in the firmware - I'll file a suggestion for that.