From my personal point of view the new A-106-6 XP VCF offers the most
features at a reasonable price - provided that you like the XP filter sound.
You get 15 different filters (4 differens LPFs, 3 different HPFs, 4
different BPFs, notch and combinations of notch and LPF). For more unusual
and dirty sounds I'd recommend the Xtreme Filter A-106-1 or Wasp A-124.

Sub-oscillators are normally frequency dividers with symmetrical rectangle
outputs like the A-115 (fixed), A-163 (voltage controlled) or A-113 (four
programmable sub-oscillators).

Best wishes
Dieter Doepfer

> I've just about got the basic sound generation/modulation portion of
> my synth completed, and now I need to start looking at subtraction.
> My gut instinct would tell me to get the A-120, but I remember reading
> somewhere that the A-120 is fairly weak as far as filters go, and
> there are others that can do the same effects and more. For example,
> you can get a low pass filter, high pass filter, or band pass filter.
> Is there a Doepfer module that maybe has all 3 combined where it's
> more flexible Or are you better off buying the individual types of
> filters one-by-one FYI I'm doing industrial music, so I guess a
> primary use of the modular will be using really gritty sounding
> saw-waves for bass lines, with the added bonus of being able to use
> the modular as an effects processor for other sounds as well. Of
> course there's no limit on what I'm willing to do with it, if it
> sounds good I'll use it. :)
>
> Also, I've heard mention of "sub-oscillators" somewhere. What exactly
> constitutes a sub-oscillator I'm guessing this would be a resonance
> filter, like what you find on a LPF. There's an EMS Synthi clone from
> Analogue Systems, Harvestman has the Polyvoks, and there's the
> Livewire Dalek and Vulcan. As far as I know these all pretty much do
> the same type of thing, just with slightly different characteristics.
> Am I missing something, or does Doepfer not have any of these more
> unique sounding modules What I've heard of these things on youtube
> is pretty impressive... just curious what options there are. Not that
> I'm wanting to stray from Doepfer, so far everything in my rack is
> Doepfer. :) I might at least pick up the EMS Synthi filter some day,
> as I love what it does when you run drums through it.
>
> I appreciate you all putting up with my noob questions, just remember
> you were all where I am, at one time. :) I've learned so much about
> sound and synthesis already, and I'm still a VCA short of having a
> "fully-functional traditional synth". Once that module comes in, I
> think a lot of possibilities are going to open for me, so I really
> need to start doing some homework and getting some advice/suggestions
> on where to go next. I've seen a lot of people who have huge modular
> setups, and do nothing but set up modular sequencers and play with
> sound generation, but I'm more interested in integrating the
> old-school modular with the new-school DAW software (Logic in my
> case), so I'm doing a lot of midi work. My case is 6U, and from what
> I gather, with probably about 1 row of modules you can pretty much
> have the equivalent of a Minimoog, so that gives me another row to
> just expand this thing and get some amazing sounds on top of what most
> people would consider "normal". :)