MOTM

> has to have at least one vco, vcf, env and vca *per 
> voice* . 
[...]
> just be sure to dial your voices up the same way  - like 
> setting up an oberheim 2/4 voice.

Polyphonic playing on a big modular can be a very special
experience. At first one might think that many identical modules
are needed, like four M-440 filters for a 4-voice modular,
or 8 ENV generators ...
But in practice, you can get good (and often more interesting) 
results with a mixed bag of modules. Using 4-pole filter for
one voice and 2-pole filter for the next, or using a VCLAG to
fill in for missing ADSR modules, is not just a surrogate
for N equal voices, but it can give polyphonic playing a new
quality.
For a start, it's good to *attempt* to set up a similar sound
for each voice. This will not be possible with different filters,
but you can set them as close as possible (like, using a slightly
lower cutoff point on the 2-pole VCF to make up for the less
steep slope). Of course playing with N totally different voices
has is benefits as well, but playing with *slightly* different
voices has a charm of its own. I don't know why, but starting with
different filters and trying to get close is more satisfactory
than using identical filters and setting slightly different 
parameters. (;->)

JH.