Hi guys,
Recently achieved long- term ambition and got my first Moog (Voyager, 251, 351 plus M’Foogers). I’m not a keyboard player, or even a proper musician, but a lapsed drummer with ideas above his station so please forgive basic ignorance! There are some areas of confusion, particularly around Mults. I gather from the manuals that these are a way to use one module to control or modify more than one other parameter; however, the mult panels on the 351 are not marked as to which jacks are in- or- outputs. For example, the manual suggests using the LFO to control 3 separate inputs on the Voyager itself, but doesn’t seem to explain how to patch up the 351’s mult panels. Am I being particularly stupid, or is there a danger of patching 2 outputs together & blowing something up if I get it wrong? Bearing in mind there are 2 mult panels on the 351, plus another on the 251, some guidance from you would help me move up a stage in my learning curve. So far, I’m enjoying myself imensely, albeit not doing anything remotely serious, but it is an amazing bit of kit…my keyboardist friends are extremely jealous - well worthwhile in itself! 
Mults don’t have specific ins and outs. Just plug your source into any jack and use the other 3 jacks for your destinations. Don’t use more than one source though…a mult isn’t a mixer and multiple voltage sources could damage something.
Welcome to the forum, Nick!
The mult is only 1/4" jacks wired in parallel. There is no “official” input, use whichever jack you want as the input, and whichever jacks are left are your outputs.
One note of caution, you must never plug more than one input into a mult, as it is not supposed to be used for mixing control voltages.
Other than that, you’re all set! Just remember, each mult always has 1 input, but many outputs.
From one drummer to another… 
Bob
It can all be confusing at the beginning, and while both above replies are right, confusion may not have dissipated all together.
The actual CV (input) is the tip. In a mult jack, any plug tip that carries a CV is ‘multiplied’ to other connections (output). You can only have one of those in a mult, otherwise they will interact together. Nothing bad will happen, but maybe not what you expected. You probably intended to use the mixer for two inputs.
Also :
Red input jacks on the Voyager carry 5 volt on the ring connection to feed in expression pedals (blue ones don’t). The exact same service is provided on CP-251 and VX 351 for all input jacks with a white circle. No harm will ensue, but you probably don’t want to insert a TRS cord with a live ring connection in a mult, again mostly because things may not work as expected.
Finally, there is not real harm to be done from using TR cable with TRS jacks, but keep in mind there are some things to know about foogers too. Foogers inputs labeled in white also carry the 5 volt ring supply in a ‘mult way’. If you want to use many inputs with expression pedals (and chances are you will want to do that) and use even a single TR cable into a white fooger input, you just shorted the ring 5 volt to ground and disabled other expression pedals from working at all. The moral of this, you probably should have a couple of TRS patch cables handy in addition of standard TR patch cables that you’ll use most often.
Did that help clear the confusion ? humm maybe not, but that’s something more to chew on
Welcome to the group and have fun with your new gear
Hi guys,
Thanks very much for all your answers - very helpful & much appreciated; also good to know there’s another drummer around, Bob! I shall experiment and see what emerges…As for patch cords, that was going to be another question; all the ones I have are described only as “1/4-inch mono” and have a single black ring at the business end…oh yeah, and something about strain relief but perhaps we’d better not go there Are these TR, or TRS? The great thing about drums was never having to plug anything in; I remember one band session ended with the axe-grinders furiously unplugging, while I noodled gently & encountered objections from certain quarters; I simply retorted “You can’t unplug me, you ba******!”…This ended up on tape - we drummers like to have the last word, you see.
Mono is TR (Tip/Ring)
Stereo is TRS(Tip/Ring/Sleeve)
Agreed! Just because we hang around with (alleged) musicians, doesn’t mean we’re not valuable! 