Elta Polivoks Filter review

[A E J O T Z]

The Polivoks is arguably the most Sci-Fi of classic synthesizers. It can sound like a giant soviet space robot that eats capitalist synths for breakfast. It's also awkwardly large, has one of the worst keyboards ever, refuses to stay in tune and has non-standard power and I/O connections. I want that sound but not all that trouble.

Fortunately, the Polivoks is a pretty conventional moog imitation (albeit one with with lots of bells and whistles) until you get to its uniquely nasty filter. That filter is what turns conventional waveforms into majestic Polivoks roars. So, unsurprisingly, Polivoks filter clones are a growing business. There have been numerous efforts over the years, including chip kits, simple effects boxes and Eurorack modules.

One of the newest entries is a little green box o' knobs by Elta offering four filter modes (low-pass, high-pass, band-pass, notch), cutoff via knob, CV or expression pedal, and even a noise generator with level control. That's more features than I've seen in any previous iteration.

Finally tempted beyond my ability to resist, I ordered one from Perfect Circuit (good people; there was a slight issue with my order and they went above and beyond to fix it).

My unit arrived today and I eagerly connected it to my Microbrute. I then proceeded to underwhelm myself by failing to make the Polivoks filter sound magnitudes raunchier than the Steiner-Parker filter in the Microbrute.

After a break I returned with more patience and less unrealistic expectations and tried again. With a little work I began to pry Pandora's box open. It still wasn't knocking me over but it was sounding much more promising.

Then I did something life-changing. I ran my Casio "Cosmo" CZ-101 through the Polivoks filter. (In case you don't know it, the CZ-101 doesn't have a filter, as such. You can program filter-like tonal changes but you can't manually filter sweep in real time.) I have, of course, run the CZ through the filters of the Microbrute, Microkorg and Werkstatt, and they sounded OK. But the combination of the CZ and the Polivoks filter is epic. I tried patch after patch and each time amazing additional harmonics appeared during a sweep. Something about the unnatural waveforms of the CZ dovetails perfectly with the unearthly Polivoks filter.

I spent an hour just noodling on the CZ with my right hand while my left hand operated the cutoff knob on the Polivoks filter. I didn't want to stop.

Conclusion: This filter rocks! But you have to overdrive the audio input to wake it up, and you have to feed it something interesting.

The only real negative I noted was that connecting the expression pedal disconnects the cutoff knob, so there's no way to adjust where in the pedal's travel the cutoff occurs. Also, the notch setting on my unit doesn't do much, but I never use notch anyway.

Rating: Before connecting to the CZ I would have said 4 stars at most.
After connecting to the CZ I say 5 stars. It's like having a whole new synth.

Your pal,
Howard AEJOTZ Tate

P.P.S. Elta just announced its Polivoks Filter version 2. For $299.00 USD you get all the above plus an LFO and a "wob" fader. I don't need those things, especially for an additional $100.00, but I thought you should know.

UPDATE 6-30-2017:

I recently got a nice dirty little Yamaha PSS-470 digital FM synth. After creating some really thick nasty sounds I figured it would go great with the Polivoks filter. Nope. Boring as hell.

Did I just imagine how great the filter sounded with my other digital synth, the CZ-101? Nope. That pairing is mind-blowing. I just spent 10 minutes holding one note down while slowly twisting the cutoff knob and asking no one in particular, "where the @#$% are all those sounds coming from?" There is some weird interaction between the CZ and the Polivoks filter that is out of this world.