There’s a saying with modular synthesizer users; You can never have too many VCAs.

Over the past few months I’ve really learned that’s true.  One corollary I’d like to add is that those VCAs should not be the same.  Having a variety of VCAs provides a wide range of sounds as each VCA adds its own subtle difference to the sounds it is processing.  As of this writing my modular has five VCAs; a Cat Girl VCA 3+, a PAiA 9710, 2 Oakley Classic VCAs and of course, a Q108.


But this post is not about VCAs.

I would like to add the statement; You can never have too many VCFs.

Filters, like VCAs and Oscillators each have their own unique characteristics.  Sometimes you’re looking for a rich, creamy filter.  Sometimes it’s a raspy biting filter.  Sometimes it’s a warm and fuzzy filter.  In any case having a variety of filters to choose from just expands your creativity pallet.

Presently in my coral of filters I have; a Yusynth Minimoog clone filter, a Dotcom Q107 State Variable filter, a Synthcube / Moogah SEM filter, a Cat Girl Steiner / Synthacon filter, a DJ Thomas White Triple Low Pass Gate and (the actual subject of this post) a PAiA 9730 filter.


As I add components to my modular I’ve learned that certain modules have a high degree of precision to them while others tend to have less. modules, for example, have an almost surgical quality of beauty to them.  They have a degree of perfection I can always count on.  I know what to expect of them (most of the time).  PAiA modules, on the other hand, are different.  I’ve described them to others as modules with a handful of sand thrown into the works.  They have a certain degree of unpredictability that has a type of charm all its own.  You can never be 100% sure of what you’re going to get when you throw them into the mix.

Migrating my FRAC sized PAiA modules to MU (see previous posts) was a great thing for my setup.  I now incorporate them into far more patch setups than when I was limited to the number of 1/4″ to 1/8″ patch cables.  Because the 9700 has the basic building block component modules for synthesis I have a PAiA feature available through all portions of the sonic creation process.

The 9730 filter is an interesting beast.  It is sometimes maligned for its unpredictability.  The 9730 can often mangle a sound beyond what you thought you would expect due to functional limitations and / or anomalies.  I won’t get into those specifics here but you can Google them if you’re interested.

One “Fix” offered by PAiA is a resistor addition modification to minimize oscillation of the filter.  This involves tacking in a couple of 4700 Ohm resistors to IC3 on the board and resetting the scale trim pots.


I performed this process and used it for a couple of months.  During that time I found I used the 9730 less and less.  It became so un-interesting.  The filter worked but without its wild unpredictability it left me flat and bored.  If I wanted a bland filter I would have searched out a bland filter (although why the hell would I do that ; ).  All my filters have unique characteristics which make me love them all.  Having worked with them for a while I now have a good idea of where to go when looking for a particular sound.  When looking for a wildcard I’d go to the 9730 (before the mod).  After the mod, however, it was just another filter and not a particularly interesting one at that.  Removing the modification changed all that.

My bandmate in my electronic band Fizzbin once said to me that he chose some of his effects pedals and synths based on their unpredictability.  He explained that not knowing what was coming could sometimes be more fun then simply dialling in a sound.  He’s right!

Un-fixing the PAiA was the best mod I’ve made in a long time.  I’m excited to have my out of control, whack-job filter back.  I wouldn’t have it any other way.