hello good folks,
just trying to better understand the cv capabilities of my mg-1 which has a trigger and a pitch cv on the back. (i think thats what they were, not looking at it right now but its the standard mg-1). i also own the freqbox and ringmod so i was trying to fully understand my options without plugging anything harmful into the old mg-1 which is the bass player in my band, and therefore crucial. any guidance would be appreciated.
If it is like my Rogue, it would have a TRS Tip Ring Sleeve with Gate In/Out and CV In/Out. You should be able to use the “Out” to your MoogerFoogers and the “In” to your Synth.
You just need a couple of stereo “Y” splitter cables with separate ring and sleeve outputs.
awesome man! i hate to sound so daft, but what exactly does the gate in/out do vs the cv in out? also, which (tip/sleeve) is in vs out? as i think i said i also have the freqbox and the ringmod, so i was looking for fun ideas with these three. thanks again for helping a noob.
No problem at all.
CV is Control Voltage. It is usually DC and can range from -15vDC to +15vDC. In this case, the CV voltage tells the VCO what key you are pressing or what pitch it should play. CV on keyboards is usually done one of two ways. There is the most common, 1 Volt per Octave (which splits the keyboard into octaves and each octave splits the key values into fractions of that volt). The MG-1 is 1 Volt per Octave. Then there is the other kind, Hertz per Octave (which splits the frequency into Voltage fractions).
The Gate is used to tell your keyboard that you are pressing a key. Gate is done in 2 different ways as well. The most common is to have +5vDC that lasts as long as you hold down the key. This is called a V-Gate or Positive Gate. When you release it returns to about 0 Volts. The other method (the MG-1 uses this) is an S-Trigger. This shorts a switch to tell the synth a key has been pressed. The voltage is high until you press a key, then it gets shorted to ground when you press the key.
You can convert a +5v Gate to an S-Trigger if you are electrically inclined. I found this diagram and other useful MG-1 Mod info at http://www.cykong.com/Synths/Moog%20Realistic%20MG-1/MoogMG-1-Mods.htm
thanks a lot bryan, that all really helps. so i think pitch on my machine would be cv, and trig would be the s-trigger. so am i correct in that if i separate tip from ring, then i could use the pitch cv out to, for example, increase the freq on the freqbox or ringmod as i travel up the keyboard?
Sounds like you got it!
Like you said, you should be able to use the CV out for lots of fun with your MoogerFoogers.
After downloading the manual, it says that the keyboard is disabled when a plug is inserted into the “Pitch” Input. So it looks like it is different from my Rogue.
Maybe you could add a jack to have the keyboard output? The Pitch Input must be a switching jack with the Keyboard CV connected, so if you can find that connection and hook it up to the tip and ground the sleeve you should have the Keyboard CV out.
so might both of those be cv inputs only?