Hi, I recently got into analog video synthesis through Mainbow and Wavecomber, but I have a few questions about the CV standard. I’m very much a noob concerning eurorack so please have empathy
Most other eurorack modules seem to operate around ±5v and up to about ±10 volts, but video modules seem to like using LZX standard for video CV frequency reasons?
If I plug 5v into Mainbow, it clips to 1v, correct? But I wish to know what the limits are so I don’t accidentally break it. Also what happens if there is negative voltage input?
I’ve just ordered the Behringer Abacus (Make Noise Maths clone) as I wish to have a module that can do LFO as well as some more complex CV modulation etc, however it seems the internal output for the LFO is a whopping +10v and generally the maximum output for all functions is in the ±10v range. I’ve noticed however that a lot of peoples’ racks include the Maths module for its variety of available funtions, even ones in video racks. How do you all keep it within LZX CV limits?
I was hoping to use a LZX Cadet Scaler to reduce output by 5:1, but that still leaves me in the ±1v range at 50% attenuation, and I dont know how to get that to above 0 volts from negative (bias/offset?). I’ve just been googling lots of things but I can’t seem to wrap my head around what the best solution would be without breaking the bank. I’d prefer a solution that can be dialled into the correct voltage range and left there, but that probably isn’t reasonable.
Probably my next choice of module will be a scope of some kind and perhaps a Syntonie LFO with the correct CV range out of the box.
I think I can use the option C scaler there and a 2:1 fixed attenuator to get even ±10v down to the range I want. Getting to this (simple) realisation has taken quite a bit of reading and learning, which is always fun. I’ll probably eschew the Syntonie in favor of a Dnipro Krait as that can do CV Looping as well as LFO / Random.
I’m slowly building confidence in eurorack, and it feels great
That ±10v to 1v scaler would theoretically solve my problem neatly, I’ll be testing it out during the summer
Edit: no I won’t because I both don’t have an extra scaler to spare, and even with the simulation don’t understand enough about whats happening to try to build one from scratch, however I might just buy one of those ±5v to 1v scalers and a 2:1 fixed atten. and begin there
I am not an EE, but I’ve been feeding Eurorack voltages into my Mainbow and haven’t broken anything yet, but naturally the functions definitely don’t work the way you’d expect. I’ve been meaning to breadboard some attenuators but I’m lazy
I’m not sure if you already realized this or not, but Maths (and therefore probably Abacus too) has attenuverters/offsets built in (channels 2 and 3), so you can scale and offset your signals there without any other modules, if you have those channels free.
So I contacted ChromaCauldron, and he confirmed that the inputs have built in protection for eurorack signals. “The LZX standard is ±1v which Mainbow follows. Connecting a signal up to ±12v won’t damage anything but will clip to the ±1v range.”
I think that’s pretty cool but I do have a question for y’all, which I didn’t get an answer for from CC - Is LZX CV range then actually ±1V and not 0 - 1V+?
Also thanks Joem for your answer, that actually does help. I keep finding new ways of using the (not) Maths module
Doesn’t help you with the Maths clone, but thought I’d note that Xaoc Zadar is pretty useful in a video context: four loopable envelopes in 10hp — and you can scale the output internally to 0-1v.
Thanks, the Zadar does look very nice just from an aesthetics perspective as well. I just got the Dnipro Krait and its been excellent for creating dynamic loops, and the 0-5v works well with my LZX fixed scaler, so it really saves on rack space for its functionality, but perhaps next time I’ll consider a Zadar.
but I do have a question for y’all, which I didn’t get an answer for from CC - Is LZX CV range then actually ±1V and not 0 - 1V+?