When not using a drum machine of some sort and wanting to sculpt and control specific tones and shapes, you’d usually think that you need a snare module, a kick module, a hi-hat module, and maybe a clap or clave module, etc., but you don’t. Not really. To keep some space in my tracks I almost never have my kick and snare hitting at the same time, so theoretically I could modulate various parameters on one percussion module with some gates, triggers, and LFOs for both kick and snare. And if there’s space in between those two, it’s possible to add something else like claps, clave, bell, etc., with some creative and thoughtful CV input, even for a single-voice module, provided the module has those capabilities. Steady State Fate’s Ultra-Perc does and is made for doing exactly this, but excels at many other tasks as well.
The newest addition in their Entity line, and successor to the original Entity Percussion Synthesizer, Ultra-Perc is an all-analog full-voice module geared towards creating percussive sounds and is really flexible with a lot of sound sculpting capability, so much so that even calling it a percussion module seems a bit of a disservice. There’s a twin resonant core signal generator and a customizable noise circuit as well. The noise circuit is great for layering snare hits or to use separately as another sound source, and there’s also an external signal input so Ultra-Perc can be used for layering more sounds, as another trigger input along with the main trigger, and you can even use it to surprisingly great success to process incoming signals, something not too many (um…none?) percussion modules tout as a feature. There are a ton of modulation inputs (twelve, to be exact) for shaping and triggering both the main circuit’s signal and the noise, and a Duck output (think avoidance, not animals) to go along with a Main out. There’s even a V/Oct input to track those resonant filters and get some bass or melody lines going, or just to change the tuning of percussion hits.
Looking at the flowchart to track the signal routing is really helpful in understanding what’s going on here, and where what’s going on is really going on. The first thing to do is start triggering Ultra-Perc, and with a light-up eye that’s a manual trigger button as well as a Trigger In, it’s easy to get started twisting knobs to hear what this module is capable of. In terms of shaping the basic internal sound, it’s created with those two resonant multi-mode VCFs and a wave folder and has a host of other basic synth features that you’d usually need extra modules for (VCAs, envelopes, noise). There are numerous controls to shape the central sound: Length, Master Tune, Detune (with selectable Lo, Med, and Hi settings), Body Bias, Harmonics, Body Decay, FM Depth, and Trigger Delay. Most of these (Master Tune, Body Bias, and FM Depth excluded) are CV controllable, which right off the bat shows how much control you have over shaping…well…everything.
It’s one thing to talk about the sculpting possibilities and completely another to hear it. Ultra-Perc can go from the lowest, shortest clicky electronic bass drum to an incredibly rich and complex synth voice, full of FM goodness, that, with the V/Oct input, can snake its way through a mix as a bass or melody line. In terms of straight kick duties, using the parameters to create whatever sound you’re looking for, whether it’s a more electric sound (acid-y, 808…) or even acoustic drum sounds—which Ultra-Perc does well—is just a matter of tweaking the knobs.
For snare, adding the Noise to layer on top really adds to the depth, and gives it some impact. The internal Noise really adds a ton to this module as you can shape the Noise sound with the LP/HP/Body (the latter, which routes the Noise’s LP response to the input of the two resonators and filter with no noise at the output) switch, the Decay, and the overall Frequency, along with the Bias, and CV all of it. It’s like having an extra module on hand, a way to accent hits, add a completely separate element, or even just to add some random background noise to your track, and with independent controls, including a VCA, you have a lot of useful options.
Sometimes I wonder how specific to get in reviewing something, like why or how something works as opposed to what it does, but in this case, I think it’s important to explain how the controls work in order to understand a bit more of the design and design philosophy SSF employs. Really, when it comes to percussion modules, a good question to ask is how would YOU want to tweak or control a drum sound. As I mentioned, the main sound is produced from the two resonant cores, and Master Tune is the overall pitch tuning for those two cores, while the Detune spreads those cores apart from each other, like siblings that can’t get along. There are three tuning modes (Lo/Mid/Hi) for choosing the overall tuning range, and this detuning helps thicken the sound for percussion, but also when Ultra-Perc is pitched higher, it starts to create a more complex tone, whether it’s the metallic clank of a broken cymbal or a folded, mangled synth line. In conjunction with the Harmonics and Body Bias (which is kind of the volume/transient shaper of the main sound as it works with a few of the dynamic parameters of the sound simultaneously), and Body Decay/FM Depth, things can be tweaked very particularly. FM is an attenuverting control so you can bring in positive or negative frequency modulation to further sculpt your sound and there’s also a Trig Delay, with up to 75ms of delay which can be layered for flams, off rhythms, and even ghost hit type of things.
As mentioned, patching it up so it can be used simultaneously as a kick and snare, and maybe something else too, becomes an interesting challenge, a sort of game in planning and preparation, and an excellent lesson in economy and patch management. To make your percussion track work well sonically in a mix, and to be able to do it in a variety of styles for different purposes and genres, seems like too much to ask for in a module that isn’t a small computer loaded with samples masquerading as a Eurorack module. I was interested to see if I could make it work if the patch junky in me could indeed utilize all of those modulation jacks in a respectful and responsible manner! It wasn’t necessarily easy to get all of those elements in one patch all the time, but with some trial and error, I was able to get a few different instances where it worked well. Usually, I’d start with the kick sound and dial in the right amount of modulation to pitch that to a snare sound. Then I’d add modulation to the noise so it would trigger at the same time as the snare, and I’d tweak the noise to my liking. From there, it was a lot of patching, tweaking, and a bit of thinking to be successful in this manner. It was quite fun, and though Eurorack rigs seem to keep getting bigger and bigger, the challenge of doing something like this made me think of the joys of problem-solving and coming up with something other than what you’d hoped or planned, but something surprising and inspiring, like I did with Ultra-Perc.
As for using Ultra-Perc to process external signals, there was a bit of massaging—really just knowing how to use it—that needed to happen to get the most out of it, and there were times when I’d have something patched in there, say a melody from Joranalogue’s Generate 3, and unless I had the settings on Ultra-Perc a certain way, the sound from G3 wouldn’t be audible. Usually, this had to do with the Length and Master Tune controls and with a little exploring I got back into sonic destruction territory, which Ultra-Perc does very well. I found myself using it as a processor for audio almost as much as for drum duties because it was so fruitful to explore in this realm. I used it quite a bit for acid-y basslines so much that at times I was hard-pressed to switch it over for percussion detail. I even got some staccato woodwind-style tones out of it with just a square wave sequence patched into the Ext In, but that’s just one of numerous surprisingly cool and useful sounds and instances that Ultra-Perc produced or processed.
This is a dense module. It’s not confusing or mysterious at all—quite the contrary—just incredibly open to sonic possibilities with a lot of inputs. While it’s set up to be used for percussion—and it’s great as that—and is able to produce massive kicks, impactful snares, hi-hats, toms, etc., it’s also a marvelous tool for sculpting sounds for leads, basslines, and overall distorted madness, and it makes me marvel at the fact that it’s all analog.

14 HP +12v 125mA -12v 125mA
Price: $379

steadystatefate.com