voltage differences, mixing modules different manufacturer

erich · Joined: Jan 08, 2007 Posts: 58 Location: US Audio files: 1

Hello,

I have wanted to build a (very small) modular system by choosing exactly what modules I want even if they are from different manufacturers. It's sort of a pain. I have a Cyndustries Zeroscillator and a couple other of her modules, and a couple Cwejman modules. I was using a metasonix TM-5 to send out an envelope control voltage to a cwejman control voltage input, but realized that some of the metasonix stuff can handle up to 20V! Am I going to break something here? I miss my computer. I also got a used Cwejman envelope I while back to control the Zeroscillator but didn't realize at the time that the Cwejmans operate using 12V, but the Cyndustries (and most of the American stuff) operates using 15V. I don't have a power supply for the Cyndustries modules yet, so I've never used it of course. If I try to use the cwejman envelope with it, is the tuning going to be off? I didn't get educated enough about this. Any thoughts on mixing modules using different voltage levels or from different manufacturers in general would be welcome, I'm not sure if this is going to work very well. I also have a moog cp 251 control processor, which uses only 5V from what I understand. Is there a good way to deal with all this? Is it just not to mix the modules like I wanted to?

oisin · Joined: Jun 16, 2009 Posts: 35 Location: germany

im starting to put together my first modular rig. some of the first modules i bought were some old elektor formants, which are 15v. i talked to the guys at schneiders büro in berlin who turned me on to a small company called curetronic that also runs on 15v, so i ordered a power supply and some modules from them.

im thinking that ill want to include some 12v modules (doepfer!) at some point, but i kinda like the way the 15v thing led me to a nice little company like curetronic. limits can be good. does that make sense?

erich · Joined: Jan 08, 2007 Posts: 58 Location: US Audio files: 1

Yes that does make sense. In fact, limitation was something I wanted very much for my little modular system. It's just that the limitation I wanted to put on myself was more about having a very small number of modules, but very carefully researching what each company had to offer and getting something put together that was very much custom made for my intentions. I liked the sound sources from Cyndustries(and some processing) but the Control Voltage options on Cwejman and the dense features made them good for getting loads of use from a single module. Thanks for your input, I'll check out that company. Analogue Systems has some stuff I really liked too.

Cat-A-Tonic · Joined: Mar 24, 2008 Posts: 42 Location: Yokohama, Japan

The only big issue for you is using different power supplies.
If you can get over having to use different PSU's to meet the need of each module you won't have too many problems.
Some Euro modules will run just fine on 15v, but they *might* not function in exactly the same way without a few modifications.

Most modern oscillators are designed to track 1v/oct. reasonably.
The 1v/oct. standard unites most of the manufacturers.
Metasonix oscillators track hz/volt, but I drive mine with the audio signal of another 1v/oct. oscillator (Blacet) and it works beautifully.

The only thing that you really have to consider is the voltage range that the modules are designed to send and receive at.
This is an issue between the envelopes and VCAs of Frac (10v) versus those of Euro (5v).
Attenuators and amplifiers can solve alot of these problems though, so there is a workaround solution.

Personally, I've chosen to use Frac as my primary rig and thus only get envelopes and VCAs in Frac.
Later, I might get some Euro stuff to supplement the system, but not get any Euro envelopes or VCAs if I can avoid it.

oisin · Joined: Jun 16, 2009 Posts: 35 Location: germany

looks like plugs can be an issue too - i recently decided to convert a bunch of older modules from banana to jack. not complicated, but alot of soldering and drilling!

ndkent · Joined: Jan 03, 2006 Posts: 66 Location: new york

I think there is some confusion here around 2 potentially but not necessarily connected issues. Because a module uses say a +12 -12v supply (be aware that it's not simply a +12v supply) it has no direct bearing on the amplitude of the envelope it generates beyond it's not going to be likely it will put out a +15v peak.

Okay, now if you are concerned about your Metasonix putting out something too hot, I'd simply set it to the max and measure the output with a voltmeter. You could also probably contact Eric or someone who knows them well to ask them what the max is that they put out. It's not going to have much bearing on the power supply and I doubt he'd put user accessible voltage outputs that were dangerous to some gear... and you would hear all sorts of uproar and warnings if that was the case

As mentioned - either PAIA or Blacet decided Frac modules should have envelopes (and thereby VCAs) responding to 0-10v while a lot of other gear does 0-5v. And then there are voltage differences between dozens of other modular systems in one aspect or another. It is easy enough to check this out with a voltmeter. You could simply attenuate any 10v CVs you want to use. doing 5v to 10v is more involved but if you have a voltage mixer just mult the 5v signal and send it to 2 inputs. There may be some home brew exceptions but generally no 5v gear would be harmed by 10v, you might just max an inut and not get what you wanted. Now if we are talking about much more than that, then yes you could fry something if you send it big voltages.

Antimon · Posted: Mon Jun 22, 2009 6:16 am Post subject:

Is CV generally positive, i.e. 0 to 5 V and not -5 to +5 V? I am asking since I can get the Motu Ultralite to output -4 V to +4 V, and have been wondering if I need to have some way to add a DC offset to use all 5 volts on my incoming Curetronic setup.

/Stefan

ndkent · Joined: Jan 03, 2006 Posts: 66 Location: new york

Antimon · Posted: Sat Jun 27, 2009 12:55 pm Post subject:

Great, that means I can make use of the full range from the MOTU, though I'd probably want to amplify it if I want to modulate VCAs. Thanks!

/Stefan

bleekza · Joined: May 11, 2009 Posts: 23 Location: Virginia USA

I'm trying to build a system with Euro, Frac, and Modcan modules.
I know I need 2 different PSUs for the Euro and Frac,
but,
can the Modcan and Frac rack modules work off the same power supply?

Also,
is there a way to get two or three power supplies on one plug and switch?
(forgive my noobiness)