Small in nature but aggressive in sound, the user will be able to create a variety of analog timbres and beats. LEPLOOP was designed to be a minimalist electronic music live-performance groove-box, which can be used to create a variety of electronic musical styles. The LEPLOOP can be synced via MIDI to another LEPLOOP for tempo-synched operation or to another MIDI device or sequencer to receive sequence stop & start.
For the easiest introduction, I elected to begin with Cassa, so named as another reminder that the LepLoop is proudly different. Google suggests ‘cash’ as the translation, possibly in a sign of confidence, because Cassa is a fine-sounding analogue bass drum. Even so, its controls don’t always behave as their labels imply. Take frequency, for example; at low resonance it barely changes the pitch of the bass drum at all, except in the last few degrees of the knob’s travel. Instead, it makes subtle tonal changes. Once resonance is involved, it behaves very differently. Resonance contributes a mad, ringing presence, and at its highest values the bass drum turns into a continuous drone. Or, when the frequency is low, it becomes a bizarre and ominous didgeridoo. With no decay control, resonance is the only way of significantly extending the envelope and adding more body to the kick.
Distortion is a rough and ready overdrive, except when frequency and resonance are both high when it performs a neat impression of a nasal filter sweep. Those three knobs offer a lot of variety even before you start to apply external processing. The final control, Accent, blends the pulses generated by Cassa’s dedicated trigger track and the track that drives the sample and hold process. Depending on the activity of either, it can be used to add fills or thin out a busy pattern. When Accent is turned fully clockwise, the bass drum is triggered entirely from the S&H track. That almost wraps it up for the bass drum, except to say that it can be sent through the 24dB filter if necessary, although at the expense of the synth sources.
Before checking out the synthesizer, it’s worth gaining an appreciation of the unusual sequencer that triggers it. Or sequencers, rather, for there are five in total. The analogue sequencer isn’t as easily spotted as the four digital tracks — Cassa, S&H, Env1 and Env2 — whose triggering is obvious due to flashing LEDs in green, red, yellow and blue. The digital tracks are purely for triggers: there’s no memory of the panel’s knobs and switches, they’re always live.
Programming triggers involves a trip into the Green menu where the SH1 and SH2 buttons are employed to enter notes and rests in step-time. Initially, it’s not always clear which track is selected, until you get used to matching the flashes to the steps marked active in the row of 16 smaller LEDs. A digital track may be up to 64 steps long but can be freely divided into four tracks of 16 steps, or even 8x8 subtracks. In other sequencers, these divisions would probably be referred to as bars. Anyway, you’re given plenty of options to make variations and switch between them in performance. More importantly, the LepLoop can be a rich source of complex polyrhythms. Not only can you specify individual lengths for the four trigger tracks, but each can run at its own clock division. Nor are you constricted to progressing through the track one step at a time.
To experience such rhythmic delights, you’ll need to enter the Yellow menu, accomplished by holding the Menu button for more than three seconds. Here, you can move the play position relative to other tracks or push the track in single clock increments — groovetastic! Further key combinations change the way steps advance, and the LepLoop can serve up everything from double-sized jumps to backwards movement or movements that defy easy description. You can also stop tracks — and without an obvious means to mute them, that comes in pretty handy.
Such flexibility can result in tracks getting out of sync. While this can be desirable, I was impressed that the LepLoop’s engineers had anticipated the need to realign them. With a single button press all the positions can be reset when necessary.
The analogue sequencer takes a completely different approach. It has a maximum of 16 steps and each step stores its value in a capacitor — analogue memory that discharges over time. The sequencer is fed from the output of the sample and hold process and for every trigger of the S&H track, a value is grabbed and stored. This keeps happening as long as the Rec function is active. Flip the switch from Rec to Loop and the recording ends, leaving a looping pattern you’d probably never have produced manually. Its output is available to the two VCOs and the filter cutoff frequency.
In many ‘normal’ synths, S&H is simply a randomness generator placed for convenience amongst the waveforms of an LFO. Here, it’s an entirely different entity with a choice of two sources for the S&H process. Depending on the selection, you get a very different flavour of generated sequence. When white noise is the source, the values will indeed be random but if the LFO is chosen instead, S&H will emit rising, falling or alternating values depending on the LFO speed and waveform.
aThe analogue sequencer also has four running modes, including ‘being advanced and reset by other tracks’. Impressive and often mind-bending, it can even create melodies where the notes are of different lengths. The sequence can be edited (in a fairly laborious fashion) by shifting the notes of each step up or down, but I realised quite soon that precision bass lines and well-tempered scales aren’t the LepLoop’s forté. You can achieve properly-pitched melodies, though, and we’ll look at how after a short interlude spent with the synth.
There aren’t many twin VCO synths that pack so many modulation options into so little space. The first oscillator offers a choice of square or triangle waves; the second, only sawtooth. Their frequencies may be modulated by sources such as the two envelopes, an inverted envelope, the analogue sequencer, S&H and LFO. Each oscillator is fitted with a single frequency control that sweeps the pitch from LFO rates up into tinnitus levels. It’s not exactly precise, but then precision would be out of character anyway. The mixer consists of a single knob that sets the balance between the VCOs and there’s a ring modulator too for yet more sonic madness and bell-like excesses.
VCO2 has a bit extra in the form of frequency modulation, with sources of VCO1, Env1 and the LFO. Already, that’s practically the whole story, but due to the matrix-like switching, the oscillators are much more versatile than you’d think. They deliver atonal cross-modulation, percussive clanks, substantial bass, cheesy vibrato and almost limitless wibbly nonsense.
Either the VCO mix, white noise or the bass drum can be processed by the filter; a 24dB analogue design with a wide range and a resonant wail like a wounded cat. It sounds pretty good and its raw output is available at the mixer for whenever drones or general insanity is required. The cutoff and resonance can be modulated separately and given that there are independent trigger tracks for each envelope, it’s a fairly simple matter to draft in the self-oscillating resonance as a source of extra percussion.
The LepLoop is more compact than it may appear in the photo, its front panel measuring just 206 x 154mm. The LFO’s waveforms are sine, triangle and square and, unusually, there’s an offset control that shifts the entire output up or down. The practical benefits of this are felt when populating the analogue sequencer using the LFO as the S&H source; the offset determines the range of pitches recorded.
The VCAs each have a two-stage envelope, and you won’t be surprised to learn that switches control their source. VCA1 has a three-way choice of noise or either VCO, plus there’s a choice of modulation source — either the LFO, Env1 or S&H. The second VCA is hard-wired to Env2, its input either the VCF or VCO1. If this sounds like a lot to take in, it is — but there’s more. Until now I’ve deliberately kept all those patch points out of the picture, but naturally they add a heap of extra routing possibilities, some of which inevitably depend on switches!
"I’ve used a lot of synths over the years but this one is something different… it’s a strange instrument. It’s small, much smaller than it appears in photos: it is part synth, part drum machine, part multi-track sequencer. I’m still figuring it all out but initial impressions are that it’s very unpredictable and slightly unstable… but in a good way." – Chris Carter, Throbbing Gristle/Carter Tutti Void.