I think its easy to say that all the Foogers are needed, but really the RIng Mod makes an increadible addition to the Voyager, as does the Delay.
The CP251 is essentially an outboard modulation bus. Its capable of quite a lot and anyone that knows about synthesis knows that modulation is whats key.
Basically you are going to want all of the Foogers, even the 101.
Look at them this way. THe 101, 103 and 105a/b comprise your filter bank. (Think about the Modular Synths’ filter bank, High Pass, and Filter Coupler modules)
Ringmod and Freqbox can be your oscillator banks (with the vx351 and cp251). The delay is the goodie effect, and the Mp201 is another ergonomic modulator.
THe vx-351 is essential if you want to use your voyager to be the main controller (if you are foregoing midi, and you are as an OS Owner). SO in that respect the vx351 is one of the more critical units if you have or plan to have a lot of other Voltage Controlled devices. Also the Voyager CV outs can go right back to its CV ins even if you don’t own another Fooger.
I think Id have to go with the Ring Mod. I was messing with the Ringmod and the Delay for about 45 minutes last night. Those have to be my favorites so far.
I own
Voyager/vx351
CP, 107, 102, 104.
Theremin (Waiting on the factory upgrade to become available)
If you get either the vx351 or the cp251 seperately, get another fooger to go with it. I think the vx351 will let you interface the Voyager wonderfully, but without another voltage controlled device I think one would get tired of simply interfacing with the voyager itself all day long, even with the cp251. Although just those two alone are great.
Id get the Vx351 (for the in out interfacing) and another fooger, so youd have a place to send all those voltages to. THen your next purchase would be a cp251 and a second fooger. (Think Freqbox)
Reading back, the CP251 would be nice for your phatty.
Be sure yo get some TRS Cables for the insert jack on the OS.
Respectfully,
Eric