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Latronic Notron

Step Sequencer By Paul Nagle
Published June 1997

Is it a hi‑tech bathroom scale? Is it a 21st‑century computer game? Is it Darth Vader's toilet seat? No, it's an innovative LED‑laden MIDI step sequencer, with the power to wring new life from your old synths. Paul Nagle pulses and flashes with excitement.

Back in the early 1970s, bands such as Tangerine Dream performed on darkened stages, their massive modular synthesizers and rows of flashing sequencer lights pulsing with electronic life. Each performance was different, each sequenced note tweaked with care.

MIDI effectively killed off the step sequencer overnight, taking the simple mechanical looping rhythm‑maker and replacing it with a completely tapeless studio, which ultimately evolved into sophisticated recording programs such as Cubase and Logic.

In the explosion of new technology, many of the physical controls we'd taken for granted were quietly dropped. But, just when it seemed that the synthesizer was to become a synonym for 'piano and banjo impersonator', instruments such as the Nord Lead and Korg Prophecy emerged, leading the way for a crop of keyboards laden with knobs, ribbons and sliders.

Into this climate, apparently timed to perfection, comes the Latronics Notron, a sequencer with all the hands‑on interaction and flashing lights absent from hardware sequencers for years.

A Flash In The Pan?

Looking like a weird blend of an upturned frying pan, the mother ship from Close Encounters, and a turtle, the Notron is refreshingly and genuinely different. Its moulded plastic case has no fewer than 87 tri‑colour LEDs, 10 stylish knobs, four equally stylish control wheels and 103 switches that rattle like marbles on a solitaire board. The Notron is a step‑time MIDI sequencer with four rows of up to 16 steps. Each of these is capable of sending note information, MIDI controllers, chords and arpeggios on separate (or, indeed, the same) MIDI channels. Unlike older analogue sequencers, it doesn't have a separate pitch knob for each step; instead a switch toggles notes on or off.

Designed for lap‑top operation, the Notron feels comfortable and is light enough (at 2.2kg) to leave propped against a convenient wall when not in use. Or to wear as an impressive codpiece, come to think of it. (Dimensions are approximately 14 inches by 18 inches by 2.5 inches high.) Let's complete the obligatory tour quickly so we can get to the interesting stuff: the Notron has a MIDI In and Out, two auxiliary inputs (for future developments such as controller devices) and an input for the external power supply. Construction is to a high standard, so there's no doubt that you're dealing with a serious piece of kit.

Trip The Light Fantastic

Each row of steps is referred to as an Element; when the sequencer is running, a chaser light loops round repeatedly between the first step and the loop point. The end point can be altered independently for each row, so you can loop patterns of unequal lengths against each other if you like. To create a sequence from an empty pattern, simply hit the Run button, then push the switch next to each step you want to play. Each LED turns red and is set to output note C2 on MIDI channel 1. As the chaser light reaches a red step, its note sounds. Hitting any switch again causes its LED to turn green, and a third press mutes the note. Being able to colour notes in this way gives you a useful function — velocity grouping. At the top of each Element are knobs for Velocity and Note Length. Directly underneath these is an LED which, when red, indicates control over the velocity of red notes. Flick the LED to green and the knob sets the velocity of green notes. This means that you can accent (or even remove) ranges of notes at will — providing that your sound module responds to velocity, of course. Toggling the LED to orange lets you raise or lower both groups of notes in parallel, maintaining their relative velocities until the maximum is reached. Winding the knob back will then restore the difference.

The Note Length knob is a handy way of making quick and dirty adjustments and, like pretty much everything else on the Notron, also lets you set note length and velocity individually for every step. Setting note pitch requires that you hit the Run button a second time, select a note, then either rotate the run knob or hit the relevant transpose interval selector, via six dedicated switches on the right. These switches transpose all non‑muted Elements by intervals of 1, 2, 5, 7 and 12 semitones, either up or down. If their status LED glows green, transposition is up; if red, it's down. In an ideal world there would have been more intervals, although you can get to anywhere you need with the options available. Using just these simple techniques, within about 10 minutes of experimentation, I was Future Sound Of London.

At the base of each Element is a control wheel and five switches. These switches control Element muting, MIDI channel selection, patch number (1‑128 — bank select is not supported), echo, controller settings, timing ratio and a whole bunch of other goodies we've not discussed yet. Because only one switch can be active at once, there's no way to suddenly mute or unmute several sequences simultaneously. The wheels can send pitch‑bend, aftertouch or any MIDI controller, with a resolution variable from fine to coarse. For example, a small movement of the wheel can be set to pan a sound instantly from far left to far right or raise the volume level from 0 to maximum.

Sequence data, plus settings for mute, tempo and so on, may be stored in any of 16 memory locations. Settings data (MIDI channels, patch number, controller assignments, and so on) is stored in a further 16 locations. Settings and patterns may be recalled at any time during playback so that if, in the midst of a performance, you get utterly lost, you can recall your base pattern and start tweaking it into looped mayhem once again.

Main Event

What we've heard so far is cool but hardly earth‑shattering. Playing back multiple sequences of notes may have been impressive 25 years ago, but today's musician expects more. Fear not! The Notron has some special tricks to take you where no man (or woman) has gone before, boldly doing things that older sequencers couldn't even imagine.

Events, one of the special tricks I mentioned above, are automated actions for injecting wheel movements into a sequence. Strange things start to happen when you program differing amounts of controller, moving in different directions, on different steps of a sequence (are you following?). For example, if you programmed a value of +10 for pitch‑bend on a certain step of a sequence, then on a later step set a value of ‑5 for pitch‑bend, the sequence would loop around until it encountered the +10, which would take effect, then, when it encountered the ‑5 value on the later step, the pitch would drop by 5, relative to the original +10 amount. The same thing would continue to happen, with the pitch gradually increasing by +5 on each pass (the difference between the +10 value and the ‑5 value). If you'd programmed a ‑10 and a +5 value, the pitch of the sequence would drop instead, taking its cue from the larger pitch‑bend amount programmed. A menu setting determines whether the pitch change should scroll around the entire MIDI spectrum, be contained within certain octaves, or simply bend up or down each time the Event is encountered. Any other MIDI controller can be sent in the same way, so if you set other Elements to the same channel, some powerful interactions are possible. Global transpose events are programmed this way too. Presumably to maintain some order in a chaotic whirlpool of generated pitches, a menu option can activate pitch fixing, whereupon a third note colour — yellow — becomes available. Once coloured yellow, steps are not transposed. This can be great for fixing the kick and snare parts of a drum pattern, for example, while other instruments cascade madly around them.

Further fun can be had by setting Elements to 'rebound'. This is a forward and backward motion between step 1 and the loop point. Pauses and skips can also be programmed so that the sequencer jumps forward or waits by the number of steps you specify. An enhancement I'd like is a random option, to really muddy things up!

Each Element starts with a default timing ratio of six ticks per step. This can be changed on the fly — a setting of three ticks making the row run exactly twice as fast — and, naturally, all sorts of odd in‑between amounts are available for experimentation. Sequences can be shifted forwards or backwards by complete steps during playback (relative to the others) to turn up some quirky rhythmic stuff. If you do this while a sequence is stopped, the new offsets are set permanently. MIDI echo can be applied to individual steps, with both the rate and amount of echoes tweakable. Echoes get progressively lower in velocity, unless you specify a repeat value greater than eight, in which case they get higher. Similarly, overdrive is a snappy way of repeatedly triggering selected notes for that Chris Franke trill effect.

At this point it's worth saying that Elements or individual steps can be solo'd at any time if things start to get too chaotic. If they haven't started getting chaotic already, there's always Supersteps to explore...

Supersteps are the Notron's way of mapping virtual modulation waveforms to notes. Far more than a simple up or down movement of a wheel, these LFO‑like soundshapes are pictured on the Notron's panel alongside Element 4's steps and can modulate pitch‑bend, aftertouch or the controller of your choice. The length of the modulation source depends on note length, and the many weird and wobbly shapes available can add subtle (or decidedly unsubtle) variations to the notes occurring at the same time. When you understand them, Supersteps can do some amazing acrobatics, providing you plan ahead and program your synth to respond to the control information being sent.

Chain Gang

Sixteen steps is the maximum for any Element, but if you need something longer, a chaining process is possible, with a maximum of 16 steps and up to 16 repeats of any pattern. The chained 'song' loops around seamlessly once it reaches the final step. Chain mode operates slightly differently to pattern mode: any changes made are non‑destructive, so that the pattern can be varied but will always revert to the saved version when it loops. You can switch between chained and non‑chained locations during playback.

Perhaps surprisingly, chords too can be programmed, either across Elements or into individual step locations. Sixteen chord memories (five preset) are available for recall, and programming new ones is a doddle. Chords can also be strummed or arpeggiated, although you'll need to adjust the timing of the strumming by ear during playback. The maximum polyphony that the Notron will output is 24 notes.


This is the gadget I've been awaiting for years: a MIDI sequencer with rows of flashing lights to create looping textures unlike anything you'd play from a keyboard. Whether you make techno, new age, or weird 'bubble and squeak' music, plug a Notron into your system, push a couple of buttons and move easily between tinkly arpeggiated patterns and driving drum and bass lines. Triggering drum loops whilst altering tempos and running bass and chord sequences at the same time is all remarkably easy and transparent.

For live performance, most other hardware‑based devices permit such revolutionary controls as Play and Stop — you might as well use a DAT for backing! Even sequencers like the Alesis MMT8 only allow you to mute or unmute existing material, but the Notron makes everything tweakable during playback. In the studio, the Notron took me on a voyage of discovery which has caused me to reassess something I once firmly believed — namely, that no machine can inspire. In fact, during the time I worked with the Notron new ideas flowed as they used to back in the days of ancient knobbiness.

There were some areas of concern, though: it was distressingly easy to lose the patch memory of the review model, which suffered from amnesia if I as much as looked at it in the wrong way. I fear that a voltage blip during a live performance could leave me embarassingly silent (or thankfully silent, depending on your point of view). Latronic are aware of this and will provide some form of built‑in protection for the production models, as well as a much‑needed SysEx dump and reload facility. My other gripe concerns the external power supply. If the Notron had been housed in a standard 19‑inch rackmount, at least the dreaded PSU could be taped down inside a flightcase. Latronic's whole philosophy presents the Notron as a performance musical controller, which is great, but surely trailing the flimsy leads from an external adapter conflicts with this noble idea?

These niggles aside, the Notron is wonderful. In contrast to most so‑called 'retro' gear, it actually moves forward to new things, rather than desperately trying to recapture something that existed years ago. I was pleasantly surprised at the sounds coaxed from some of my existing gear — which shows that there's unexplored territory in even the most tired synthesizer. Controlled by you and the Notron, there's life in those old synths yet!


Ever started working with the perfect sample loop only to find you want to alter the tempo of the song? The Notron has a nifty little feature, called Beatwrap, for those working with sampled loops. Once primed, this uses a combination of transposition and pitch‑bend to ensure that, as you change tempo, the loop always stays in time. It works like a charm if you obey a few simple rules, such as setting bend range to ±2 semitones and mapping the loop over the entire useable range. Some people will buy the Notron for this feature alone, I'm sure.

Subtle timing variations aren't normally associated with step‑time sequencers, but with the so‑called Beatcreep it's possible to shift individual steps or a whole Element by increments of four milliseconds. One use for this might be to give a 'pushed ahead' feel to hi‑hats or a delay to a tom roll. But all this complexity doesn't come without a price. With no display other than coloured LEDs, it can be quite difficult to tell which type of information lurks behind each step, and sometimes tracing that elusive transposition event recalls something involving needles and haystacks. Because so much is possible, I initially had to make frequent references to the manual (a pretty good read, but it needs an index) since some of the more obscure functions aren't totally intuitive.

Other odds and sods include a PIN system which, when enabled, will make sure that your Notron cannot be activated by anyone except yourself.

Clock Watcher

The Notron features a dedicated tempo control, but no conventional readout. Instead, tempo is shown by the position of coloured LEDs on the Element grid. A single movement of the tempo knob displays the current value without altering it. This isn't as bad as it might sound, and you soon discover the joys of setting tempo by ear rather than looking at a number. While the grid display is active, you can jump directly to a new tempo by hitting any of the 64 Element switches. The Notron transmits and receives MIDI clock information. It also sends Start, Stop and Continue messages, although the review model didn't seem to recognise Continue messages sent externally. I'm told that production models will respond to these correctly.

During my time with the Notron, I synced up to Cubase, switching to record whenever anything interesting started to happen. That way I got the best of both worlds, being able to chop stuff out of lengthy improvisations and keep just the good bits. A feature familiar to Cubase users is transposition into alternate scales, but it's rare to see this implemented into a hardware sequencer. Of course, you've probably gathered by now that the Notron is no ordinary sequencer, so I'll just tell you that 30 scales are available to process notes in each row. If you like, you can set each Element to a different scale — although you shouldn't expect any instant number one singles with this technique. The available scales include melodic minor, Lydian, Balinese, Persian and Arabian.


  • A truly interactive sequencer.
  • Looks amazing.
  • Gets new mileage from your existing synths.
  • Simplifies sample loop transposition.


  • External power supply.
  • Review model lost its memory occasionally.
  • Currently no SysEx backup facility.
  • Price will put some people off.


The Notron dares to be different, allowing you to manipulate MIDI in ways that would be almost impossible with anything else. Die‑hard synthesists will love it, as will anyone who doesn't regard a five‑octave plastic keyboard as the only suitable controller for a synthesizer.