Slaving a 16 step sequencer to incoming clock pulses from Volca


#1

To achieve this I imagine some sort of PLL configuration, an default tempo needs to be corrected to the time between incoming clock pulses,can anyone give me an indication of how this could be solved?

For clarification, the volcas produce a 2 ppq output, so it can't be directly coupled to a counter without doubling the frequency.


#2

The easiest way to sync Axoloti and Volca is the other way around, since the Volca wasn't really made to do MIDI Out. Which mod are you using to have MIDI out on the Volca?

Continuing the discussion from Midi clock out patch how to:

Guess you'll have to do some trial and error to figure this one out and play with some of the math objects. This is how MIDI clock sync works with Axoloti: The midi/in/clock object syncs at a tempo of 24 ppq. If you divide the output of the pos24ppq by six, you'll get the tempo at 4 ppq. If you divide that by 16, you can use the remainder to step through a 16-step sequencer. The patch on the right does the same as the one on the left. Divide by 6 is calculated inside the midi clock object to get the value for the pos4ppq outlet.


#3

So sorry, i was referring to the Clock Out of Volca, no Midi involved at all!
This output is one pulse per eighth note which makes it quite tedious to sync a 16 step sequencer without going half tempo.


#5

What do you use to convert Volca sync to MIDI? Stereo mini jack soldered to mid three pins on a DIN connector?


#6

Oi why did you remove this, I can still see it in my Gmail inbox. Doesn't it work like you thought? O_o
I was about to say thanks for the seemingly quite simple solution!


#7

Sorry I can post it again. I just thought it wasnt relevant when I read the " no Midi involved at all!" part. I thought you wanted to sync without midi at all. Anyway here you go :smile:


#8

A PLL-ish solution is the way to go. I think this needs/deserves a dedicated object.


#9

It is basicly:
24X4=96
96/3=32

But it actually gives 16th not 32th. This way you can divide the clock AND multipy to make it slower or faster.....

Edit:
And I have testet it. I use this setup all the time.


#10

this does not add subdivisions to the incoming pulse


#11

Yeah I considered that at first, but I realized that I wanted to go for a regular DIN connector.. Had to put some spacers to make it work, not a beauty really but I was in a hurry. :smiley:


#12

@johannes

WHat does PLL mean? :smile:


#13

Phase Locked Loop : https://en.wikipedia.org/wiki/Phase-locked_loop
I've used this circuit with quite some difficulty: http://datasheet.octopart.com/NTE989-NTE-Electronics-datasheet-39538.pdf


#14

No, true, doesnt add division.. But division is easy to make. There are already a few versions in here, so I didnt include it in the pic. That might have been a bit misleading....

It took me a little while to figure out how to divide by 3, but I found out the math/divremc could do it.


#15

No subdividing tempo is a different thing than dividing/multiplying the position index number.

Musicians are often familiar with the task, you hear a pulse per quarter and then you need to play 16th notes.


#16

I am not so technical guy, more musician as you mention :smile: So I am not 100% sure that I use the right vocabulary...... but the set up works for multiplying the incoming clock. I use it all the time. But I have encountered a few issues using this setup and logic counters to set step length of a sequencer.. Then I notice that it doesnt sync. I am not sure why, but it might be related to what you say..... But when using divremc for step length it works as a "clock multiplyer" and syncs to any incoming midi clock.


#17

"Normal" Midi clock is fast, at 24 pulses per quarter note. For up to 32th notes and 8th-triplets all required pulses are there. @mackemint asked how to add the pulses when only 2 pulses per quarter arrive. This needs a timer to add in-between pulses, and adapting to tempo changes...


#18

Cool :smile: What I am trying to say is that there are more than one way to reach that goal. My version might not be intended but it works. I can multiply the clock to have 2 beats pr quarter note or 4 beats pr quarter note or 128 beats pr. quarter note, etc. with that setup. I use the clockmultiplyer to change the subdivision, for example 16th notes at 90 bpm is the same as 8th at 180 bpm. And you can change the bpm on the incoming midi clock and it will adapt to tempo changes as well as any other setup. But yeah, my setup wont work for triplets fro example, that you are right about... But for "straight" clock signal it works and in my setup having a "flexible" clock, is really important. So I favour that above triplet, etc..

A new object for this would be nice, sure :smile:

Again I might not use the right vocabulary..... But it works for all purposes that i have tested except for triplets, etc....


#19

Guess I'll stick with using my Volcas as slaves. Don't want to drill holes in them.


#20

I wrote a little object (experimental) to slice my volca sync puls into subdivisions. e.g. create 1 to 8 sync pulses for each volca sync. It also computes the bpm from a volca sync puls. @mackemint Maybe this is what you are looking for?

volca.axo (1.5 KB)
volca.axp (3.4 KB)


#21

Thanks, I'll defo give it a try, thx!
I found that the Volca doesn't seem to use a PLL as I originally thought, when changing tempo from a low tempo to a high tempo it gets out of phase..