Modulation Generator External Frequency Sync

electriceddy · Post by **electriceddy** » Fri Jan 02, 2015 2:08 am

Is there any way to control the MG frequency rate so that it's in time with an external step sequencer?

In my setup the step sequencer is driving the MS20 and a Korg Volca beats, however, the MG frequency is out of time irrespective of where I position it.

It's sounds okay at first, however, when the frequency drifts away from the beat it sounds bad until to drifts back into sync for a few more bars.

Redmond Barry · Post by **Redmond Barry** » Fri Jan 02, 2015 2:54 am

There is no way to sync the MG frequency. I believe this because the MS-20 Mini is all analog and digital LFO's are the ones that can be synced.

electriceddy · Post by **electriceddy** » Fri Jan 02, 2015 4:18 pm

Okay I see. So what's the normal approach to get analogue devices in time with digital equipment? Is it possible to switch off the internal generator and use an external pulse?

OpAmp · Post by **OpAmp** » Fri Jan 02, 2015 10:36 pm

Hi,

Just to be exact...

The frequency of the MG (LFO) of the MS20 can not be synced to something else by construction of this synth. The frequency parameter/knob can not be patched. So it is a free running LFO. It has nothing to do with analog/digital worlds.

There are both analog and digital LFO's that do have sync capabilities. E.g. the LFO waveform is restarted each time a new key is hit. Depending on the implementation, the sync signal can even be patched with other more exotic combinations. (But not on the MS20...)

On the MS20, you can of course use an external modulation signal, which you need to insert in the "Total" input. This effectively replaces the MG by the patched signal. Note that the signal must be in the -5, 5V range.

Now where you get that signal from and in sync with your sequencer? That is the question... Especially, because I think you are using a digital MIDI sequencer, which is the master clock in your system. Then it is not immediately possible.

In general, from digital to analog, you need dedicated equipment. I'm not sure there is a one fits all solution...
These days you see hybrid analog/digital synths also outputting gate and CV signals to control external analog modules, which can be a starting point for your MG problem.
You have also euro-rack modules which convert certain MIDI messages (digital) to gate and CV signals (analog).

Have fun!

mmarsh · Post by **mmarsh** » Wed Jan 28, 2015 12:47 pm

A quick google of "MIDI Clock to CV" turned up a lot of possibilities.

Jamie Munro · Post by **Jamie Munro** » Wed Feb 18, 2015 9:43 pm

Rudimentary but you could patch the momentary switch to the MG input and set that to the cutoff or pitch and depending on the ar settings you can create what is ultimately a square or triangle type modulation , obviously then syncing it is how good you are at timing your presses with the clock you are chasing

Longer track and release is longer triangle, you get my drift.

Frenzies · Post by **Frenzies** » Wed Feb 18, 2015 11:41 pm

I'll be honest with you, it's not great to sync the MS-20 LFO up to external unless you have an external cv LFO signal to send in to it. That's what I use, from the Microbrute, but that doesn't help you. There is a way to get something going on, which is to send the sync out from your Volca in to the Ext Signal In on the MS-20 and send the envelope generated out to the total or one of the filters. This is ok if you want something synced at that speed and are happy for it to sound like a square wave LFO. You're never going to get a nice 4 bar sine wave LFO from this but it is better than nothing. You get slightly different effects changing the sync polarity on the Volca. I tend to use the Volca sync as the clock source for the sample and hold circuit on the Ms-20, which can give some nice effects.

Jamie Munro · Post by **Jamie Munro** » Thu Feb 19, 2015 10:31 am

Yes I came across a chap online recently called augene (I think) that has created sync mods internally and tbh it didn't sound that great, he has a Pwm mod that was lovely but somehow the ms didn't sound right synced-maybe that was his mod, maybe not who knows.

Search ms20 mini mods to find him or others out there willing to show you how, he offers pic by pic tutorials along with text so if you gave the balls and a solder iron you are ready to go

Might be worth making sure your warranty us expired also though as I'm sure mods will void it