Friday 24 December 2021

Alesis Micro Gate: Bring Her Not Forth

Let's have a quick look at the Alesis Micro Gate, or MICRO GATE as the manual calls it. It's a compact effects box from 1988, the tail end of the Physical Age, before everything and everybody ascended to The Cloud.

The Micro Gate was part of Alesis' compact, budget-priced MICRO SERIES. I don't have access to any sales figures, but judging by eBay listings the two MicroVerbs sold like hot cakes, the Micro Limiter compressor less so, the others not so much.

As of 2021 they're all totally obsolete, the Micro Gate doubly so because it's a humble noise gate. It turns off the volume when the incoming signal falls below a certain threshold. Noise gates are often used by guitarists to get rid of mains hum and clicking noises, but they're also useful as a way of imposing a volume envelope on arbitrary sounds, e.g. they make things sound stuttery. In this video I use the Micro Gate to make a drum loop more interesting, by chopping bits out of it in real time:


When it was new the Micro Gate at the home studio market; the kind of musician who might have an Atari ST and an Akai S-something sampler. For the most part the used market for synthesisers and analogue effects has been mined out - eBay prices are famously over-the-top - but there's a rich seam of affordable digital rackmount effects and 16-bit studio gear from the 1990s that can still be found cheaply.

For good reason, too, because digital effects units from the 1990s generally didn't have any special magic about them. Computer plugins have replaced them all. Objectively the Micro Gate doesn't make a lot of sense in the modern age, but I was curious about it and found one going cheap, in very good condition, so I decided to build up my collection of Alesis effects.

The Micro, Nano, Pico etc effects had a standard back-panel layout, with unbalanced 1/4" sockets plus a TRS control socket. They all used uncommon 9v AC power supplies.

The Micro series was launched in 1986 with the MICROVERB, a 16-bit stereo reverb with sixteen non-editable presets. It was housed in a 1/3rd-of-a-rack-sized case that could be screwed into a metal plate for rackmounting. In 1988 Alesis continued the series with the MICRO GATE, MICRO LIMITER, and the MICRO ENHANCER, a exciter.

The company also replaced the original MicroVerb with the MICROVERB II, which was similar but with greater bandwidth and slightly different presets. I have one! It would have benefited from EQ, because it has a very bright sound, but it's surprisingly decent for a budget reverb from the late 1980s.

There was also the MICRO CUE AMP, a headphone amplifier. Overall it's a peculiar range. You'd think Alesis would have thrown in a delay or chorus, but no. In the 1990s Alesis continued to make third-of-a-rack effects under the NANO and PICO names, although confusingly the later MicroVerbs were housed in full-sized 19" racks, so they weren't micro any more.

As you can see the later NanoCompressor is less deep than the Micro effects. Perhaps it has a smaller PCB.

What's the Micro Gate like? It's very simple. The threshold control sets the level at which the gate cuts out the sound. The delay knob controls how long the gate stays open - it's a bit like the ON knob on a VCS3 synthesiser - and the rate knob controls the speed at which the gate closes. With the delay knob counterclockwise and the rate knob clockwise the effect is jarring, with the knobs turned the other way the result is smooth.

Now, it's worth pointing out that noise gates only turn off the volume. They don't do Dolby-style noise reduction; you can't use them to remove hiss from a signal. You can only turn off the signal during the quiet bits. Even in 2021 real-time noise reduction is difficult and the results are usually unimpressive.

By itself the Micro Gate is a bit dull, but it becomes interesting when you plug something into the trigger input. The trigger input activates the gate when it detects an incoming signal. In the video above I use a kick drum pattern from a Korg Volca Beats drum machine to trigger the gate. The result is a kind of synchronised tremolo effect that sounds awesome if you feed a large, sustained chord with masses of reverb into it.

The effect was used a lot in dance music in the 1990s. The first example that springs to mind is Olive's "You're Not Alone", where the very first sound in this video is a chord sequenced played through a noise gate that isn't quite on the beat:


That's a particularly good example. The effect can be achieved in several different ways, but the strings in "Alone" are chopped without any change in tone, in such a way that the sustain tail of the preceding notes bleeds into the notes that follow it. The notes don't have an obvious attack phase. It's hard to describe in words.

The same effect pops up in Paul Oakenfold's "Southern Sun" and probably lots of other records, although it's hard to find an example that's unquivocally made with a noise gate, and not side chain compression or an arpeggio triggering a strings sample.

You know, I've just spent the last fifteen minutes listening to late 1990s trance on YouTube. There's something heartbreaking about late 1990s trance. Not just because they dreamed of a happier future than the one we got. Behind the maximalist production and slick videos there's an underlying sadness to trance music, because the weekend will soon be over.

Trance music is a scream of defiance directed at the unstoppable force of entropy. Death will claim us all, but not tonight. Not tonight.