Page 2: Analogue Solutions Impulse Command

Sequencer 2: MIDI Loop

The Impulse Command's love of MIDI is consummated in the MIDI Loop Sequencer. This is probably based on the one found in Analogue Solutions' Treadstone synthesizer and is a simple and fabulously fast way to sequence notes into the Impulse Command. With the sequencer in 'stop', enable the MIDI Loop and whatever 16 notes you play next will be stored in the sequencer and played along with the Sequercizer. You can alter notes during playback — that's a little bit of a hit–and–miss affair if you're trying to do something specific, but a load of fun during performance if you're not too fussy. Turn on the Transpose button and can use your keyboard to transpose the sequence rather neatly on the fly.

The Impulse Command's less than conventional front panel — how many of your other synths have an 'Aggro' knob?

There's a Step button so you can select individual steps and change that note when stopped. The Step button can also force the Sequercizer to skip steps but doesn't affect the MIDI Loop and so potentially changes their relationship. Nothing's very certain in this synth. Just when you've got the measure of it you'll discover another way to mess it all up in really pleasing ways.

One thing missing from the sequencer/Sequercizer is any control over the gating. There are no gate patterns or 'rest' options. However, the MIDI Loop Sequencer is designed to give you some rhythmic flexibility. Rather than using the repetitive emotional void of MIDI Clock, the Impulse Command responds to MIDI Note 0 for step advancement. So, you could run a series of Note 0's from your DAW in a loop and generate all sorts of rhythmic patterns. You can also use Note 1 to reset.

Effects

At the end of the signal chain we find eight digital effects; a few delays, reverbs, a flanger and bit-crusher. Some in mono and some in stereo. Each effect has two parameters you can play with and there's a wet/dry mix knob at the top. The effects are nice and helpful but they also form part of the game of uncertainly that Analogue Solutions are playing. The Effects knob rotates all the way through the options without a click or a line on the front panel to let you know what you've selected. It's not difficult to work out, but it feels like a deliberate attempt at getting you to 'go with it'; to not be concerned about the precise selection but rather to feel your way into it.

Patch

And that brings us to Patch. This is the Impulse Command trump card. It's the unexpected and probably uncalled–for feature that you didn't know you needed, and even after playing with it for some time you still don't really know if you do. It's deliberately mysterious — Tom declines to answer any questions about it other than to suggest that it's there for exploration. If you've been trusting the synth and going with it so far then this is the moment of truth, this is the leap into the void. Perhaps I'm getting a little bit over dramatic... Basically, Patch does some re-routing voodoo behind the scenes and gives you something different to play with. I'd like to say it's like a preset but it's more like a curated patch.

There are eight patches using four internal signal routings, and through the use of MIDI velocity and the Sequercizer (oh yes, there's a send knob for Patch too) you can make some wild changes to what's going on. At a guess I'd say one patch removes the VCO 2 and sub, another throws the envelope on to the filter, another brings in PWM, another introduces noise and so on. The practical upshot is that you can select different patches for each step, which leads you into some rather nice rhythmic noise and percussive sounds interplaying with the duelling synth and filter melodies.

Connections

Although Tom has cooked up a certain amount of pre-patched goodness for you, it's also nice to find a decent–sized patchbay that releases you from playing the game and lets you inject some of your own modulations. You have CV inputs over the oscillators... no I was completely wrong, there's no escaping the game. There are two CV inputs that affect the pitch of the oscillators. The first one affects both oscillators like you'd expect, but the second one just affects VCO 2. So, plug the CV out of the Sequercizer to the VCO 2 input while running the Patch and the filters and the MIDI Loop Sequencer and we're into a whole other ride again. This thing is proper mental.

There's also a CV input on the PWM, the cutoffs of VCF-L and VCF-R, and a clock input to run the Sequercizer. The sawtooth waveforms of the two oscillators get an output each, which are asking to be plugged back into the pitch input for some sync/FM–style action. For modulation you get the triangle output of LFO 1 and the square output of LFO 2 that we didn't know we had. The envelopes get a trigger input as well as an output, so does the clock. On the back is the all-important stereo line output and a mono–mix output which I guess is important but seems a bit self-defeating. A single line–level input will patch some external gear directly into that dual filter. And then there's a MIDI in and a super helpful MIDI thru to make it a lot easier to integrate with other MIDI gear.

The patchbay doesn't give you every possible output. There are no individual waveforms, no resonance control or control over the Aggro or Effects. There's no Eurorack–level VCA output for the synth as a whole. But there's enough there to get the Impulse Control to mess with itself and be messed with by external means.

Conclusions

The Impulse Command challenges the notion of what a semi-modular monosynth should be. When you appear to have four melodies going on at once you start to doubt your synthesizer competence. The Sequencizer manipulates you as it starts to throw the filters around into different spaces, while repatching things you didn't quite expect and running off with a tune on the second VCO. All this while the MIDI is looping through a sequence as the velocity modulates the sub and the filter. It's an adventure playground of craziness, and just when you think you've got your balance you lose your footing and swing off down another pathway.

The oscillators are thick, the filters delicious and the envelopes are snappy enough to turn the whole thing into a percussive noise machine. And yet it's also capable of sweetness and tone that gives you some welcome respite before you start dialling the crazy back...

The Impulse Command is not a straightforward subtractive synthesizer. It won't give you the pure experience of the Mother-32 or the cerebral West Coast pathways of the 0-Coast. It's a rollercoaster journey of discovery in a fat, oozing wedge of synthesizer — or perhaps we should call it a sonic realiser.