FAT Resinator Filter

Paul White takes two migraine tablets and has a nice sit down before tackling the 'eye‑catching' Resinator filter unit...

The Resinator is the latest in the line of FAT processors with drug‑related innuendo woven into their product names. It's a rather quirky, filter‑based unit that can be used to add interest to synths and othersources that don't already have resonant filters built in, and despite its rather flimsy engineering, knobs that slide off at the slightest provocation, and a front panel that doesn't so much look silk‑screened as sneezed, it's capable of producing some cool sounds.

Purest Green

Powered from an external PSU that looks rather more substantial than the aluminium rack unit it plugs into, the Resinator is an all‑analogue processor based around not just one but three sweepable, Vactrol‑controlled band‑pass filters. There's no MIDI trigger facility, which is rather limiting in some ways, but the filter sweep may be controlled either from the input signal's own envelope, by an internal LFO, or from an external source. It's also possible to sweep all three filters from a single front‑panel control, which is useful for adding those impromptu sweeps mid‑performance.

Everything about the Resinator, including the front panel of 'purest green', is weird. For a start, the filters all have a fixed, fairly high resonance, and the front‑panel Resonance control really just balances the dry sound with the filtered sound. Each filter may be set to a different frequency and the unit has a degree of stereo capability, achieved by routing filter 1 and filter 3 to a pan control and keeping filter 2 centre‑stage. The input is mono. The other notable bit of visionary weirdness is the way the envelope follower actually comprises three independent, frequency‑selective followers, each of which controls the frequency of a different filter. The low part of the envelope follower controls filter 1, the mid part controls filter 2 and the higher harmonics control filter 3, so the filters will interact in different ways depending on the spectral composition of the incoming sound and the setting of the filter frequencies. This characteristic, combined with the stereo output, is probably the most interesting and creative aspect of the Resinator. Unfortunately, the attack time of the envelope follower is fixed — you can only adjust its decay time.

Given the OTT nature of the front panel, the Resinator's rear is uncharacteristically spartan!The filter frequencies may also be controlled by an onboard LFO, but even this isn't straightforward. The LFO actually comprises two oscillators running at slightly different speeds, and LFO 1's output can be inverted, making it possible to create three different sources in total. Both LFOs claim to generate a sawtooth waveform rather than the more obvious sine or triangle wave, but the result sounds more like an asymmetrical triangle wave to my ears.

Not content with having three possible permutations of modulation source, the Resinator routes these to the filters in different ways, so that, with the exception of LFO Mode 1, not all the filters are swept from the same source. Indeed, in Mode 3 each of the three sources is fed to a different filter, and as LFO 1 and 2 run at different speeds, this can make for some unusual stereo panning effects. Mode 2 routes LFO 1 to filters 1 and 3, with LFO 2 driving filter 2.

Control Freaking

If I've engaged your curiosity, read on for a quick sprint through the front‑panel controls. As you might be able to tell from the accompanying picture, the legending is very difficult to read because of the shiny aluminium and the virulent green patches around the knobs — it's as though somebody has loaded a handful of caterpillars into an air rifle and let rip at the front panel!

Going from left to right on the front panel, the Pan control shows up first. This changes the stereo pan position of band‑pass filters 1 and 3 relative to filter 2, which is always panned centre, as I mentioned above. The Resonance knob is simply a dry/effect balance control, and has no effect at all on the filter resonance, which is fixed. The Volume control sets the output level of the effected sound, and a Bypass switch allows you to return to normality once in a while.

Each of the three filters has its own frequency control, and though no calibrations are provided you can get everything from a bass 'whumph' to a thin 'zweee', with a range of 'fhwizooophs' in between. The LFO section has just two knobs, for depth and rate, and a three‑position slide switch for the different modes, as described earlier. The LFO rate is variable, from extremely slow to around 2Hz, but I'd have liked a range switch to get much faster sweeps as well. The Envelope Modulation section also functions with just two controls (Depth and Decay), while a polarity slide switch allows the envelope to push the filter frequency either up or down.

Finally, there's a single control for Man/Ext Modulation, and if nothing is plugged into the rear‑panel modulation jack this knob provides a manual means of sweeping all three filters together. With an external source connected, the control can be turned left of centre to enable the modulating source to push the filter frequency down, right of centre to push the filter frequency up, or centred for no effect. Positions between these extremes provide proportional amounts of modulation. This external input seems to track the envelope of the external signal rather than feeding the signal direct into the filter modulation circuit, so while it's quite predictable in operation, it precludes those nice quasi‑ring‑modulator effects that can be achieved by modulating a filter with raw audio.

You can get everything from a bass 'whumph' to a thin 'zweee', with a range of 'fhwizooophs' in between.

Fat Sounds?

Considering the large number of controls on the Resinator, it seems capable of producing only a fairly limited range of effects, and because of the rather unorthodox system of having three different filters, each often doing its own thing, the results aren't always predictable. However, some of the treatments that can be coaxed from this little box are both interesting and unusual in a musically useful way; especially nice is the way the filters create a dynamic stereo image from a mono source. Adding movement to pad sounds is easy, as is adding a fairly normal envelope sweep to a percussive synth sound, but the lack of MIDI Note On control means that the triggering varies depending on whether notes overlap or not, and the lack of an envelope attack control limits the kind of sweep effects you can create.

Another limitation is the fact that the filters have a fixed resonance, so all the sweeps are quite rich, and because the filters are band‑pass rather than low‑pass, you can find the low end disappearing on certain settings. Despite all these idiosyncrasies, the Resinator is great fun to play around with, and it is possible to come up with some unexpected effects that are not readily available from any other source — other than, perhaps, a complicated modular analogue synth system. What's more, it doesn't seem to add much in the way of noise. My old Kawai K1 sounded much more dynamic and involving after being Resinated.

Summary

It's flimsy, the knobs slide off, it looks awful, the controls don't make a great deal of sense and you can't read the knob legending — but in spite of all these things I find myself quite liking the Resinator. Very often, the most interesting sounds come from imperfect equipment or equipment that imposes certain limitations on the user, and this is definitely one such box. If it had been perfect, it would probably also have been predictable; as it stands, the Resinator provides an admittedly narrow range of unique treatments that can make the most jaded old synth sound modern and interesting. Anyone into techno or other experimental musical forms would probably find the Resinator quite useful, and because it can be controlled directly from front‑panel knobs it is also suited to live performance, or recording where some form of live interaction is required.

This isn't a box to buy if you want to sound like something you've heard on record (unless they were also using one of these things), but if you want to break a few barriers and turn boring mono sounds into coruscating stereo festivals of sweeps and glittering harmonics, the Resinator might just be the ideal way to spend a couple of hundred quid.