Continuing their line of all-analog modules named after tracks from the Cocteau Twins album Treasure, Expert Sleepers have released Aloysius and Amelia, a pair of good/evil sounding twins that are actually quite similar, enough that they could be siblings.
The youngest of the two—having been most recently released into the world—is Aloysuis, and is an AHDW (say what?!) envelope. It’s almost like a trick on the mind, right? We’re so used to AD, ADSR, even DADSR envelope generators, what the heck is AHDW? Well, it stands for Attack, Hold, Decay, and Wait. The “Wait” part is interesting on a feature level as the module’s namesake, Aloysius, was an aristocrat who gave up his inheritance to become an ascetic member of the Society of Jesus in Rome, and who wound up dying at age twenty-three while caring for patients during the plague in Rome. If anyone knows about patience it seems like he would, and it only seems appropriate that he has both a song and a Eurorack module in his honor.
I’d never heard of an AHDW envelope before, though according to the Expert Sleeper’s website that shape of envelope is known for being able to make a trapezoid shape (which will always make me think of a Simpsons episode where Homer almost falls victim to—not a pyramid scheme, but a trapezoid scheme! Season 3, episode 12 if you need to know.) Aloysius has all of the trappings you’d expect from a full-featured envelope; a Gate Input, an Output, and CV control over each of the four stages of the envelope, those being the previously mentioned Attack, Hold, Decay, and Wait. There is a way to set the shape of the attack and decay part of the envelope shape via two small knobs on the module and the small Attack shape knob goes continuously from exponential to logarithmic, with a linear shape in the center position, and the Decay works in the opposite fashion. The features on Aloysius are rounded out by the three small toggles at the bottom; the top switch for the Mode (Auto, Hold,and Gated), with the middle and bottom switches setting the ranges for the Attack/Decay and Hold/Wait times, those being Med., Slow, and Fast.
While the Wait and maybe the Hold functions might be unfamiliar to some, the operation of Aloysius is straightforward to anyone that’s ever used an envelope generator and it just takes a little bit of scouting around to see what makes this an attractive EG. There’s a lot of flexibility in the shape and times, with the ability to control the time for all of the stages—either manually or with CV—as well as tweak the Attack and Decay stages to your liking.
The three modes are really what set the tone of versatility here. Gated mode is when the inputted gated length determines when the envelope starts to decay, while the Hold stage has the Hold control itself determining when the shape goes into the Decay mode. You can get bonkers CVing the Hold, no matter what signal you have at the input. It’s a kind of hierarchy of sorts, with Hold having seniority, so watch out!
When running in Auto mode, Aloysius triggers itself and becomes a very flexible LFO with the ability to make some complex and interesting waveshapes (like trapezoids!), and this is where the Wait makes its presence known as it determines the space between the shapes. It was definitely helpful to run Aloysius into the Mordax DATA (what else) to see the shapes taking place and how to space them out via the Wait control. It was pretty wild to see how interactive the controls were, and it can be confusing at times not understanding why one parameter would have no effect, due to another stage hogging all the available time.
Amelia, the good-natured sounding envelope generator is very similar to Aloysius, and is just as idiosyncratic in nature as it’s an ADBR (huh?!). Yep, it seems Expert Sleepers has an aversion to, or just rather prefers something different, to your everyday, run-of-the-mill ADSR. For the most part, this EG is the same as an ADSR, with the Break stage being the tattoo, the pink hair, the bad attitude, that sets it apart from the din of other generators de envelope. Again, CV control over the entire stage set is provided, as are the two shape controls for the Attack and Release Stages. There are two switches this time; one for Mode (Auto, Break, Gated), and another for Time (Med., Slow, Fast) for control over all phases of the waveform.
Expert Sleepers notes that Amelia was designed for using with sequencers that don’t have an adjustable gate length out, only simple trigger outs—of which there are many—to be able to create complex shapes from that basic trigger, and that’s all well and good, but the real question, the difference maker, is the Break function. Is it better than the normally found Sustain stage? What does it do differently?
Well, while all three modes are somewhat similar, when Amelia is in Break mode the envelope falls at a pace set by Decay to the Break level, whereupon it goes back to zero at a time set by the Release function, so in essence, Break is when the envelope change from the Decay to the Release stage. With this, if you max the Break level for all purposes, you eliminate the Decay stage, and vice versa, you can eliminate the Release stage by setting Break at the minimum setting. Some of this feels like envelope generator calisthenics, and I suppose it is, but it ‘s interesting in practice as well as theory and gives Amelia the ability to be very complex in its waveshaping capabilities, and also simple, just your little ol’ AD envelope.
Aloysius and Amelia are good fun, very functional, flexible, and a nice change of pace. Slightly different than pretty much any other EG’s out there, they offer pinpoint control over almost every aspect of the shape, time, and length, stage of an envelope, and you can really create some unique envelope shapes and LFOs with both. I do wish there were inverse envelope outputs available on both modules, though I was easily able to do this using an attenuverter (I used the Zorx 1U CV bus, which is a four-channel mult/attenuverter).
Expert Sleepers have three more tracks (Cicely, Otterley, and Donimo) to go before they run out of tracks (and modules?) for their Cocteau Twins Treasure-themed line. It’s really coalesced into a great series and I’m excited to see how it rounds out.

Aloysius
8 HP +12v 43mA -12v 25mA
Price: $185
Amelia
8 HP +12v 33mA -12v 33mA
Price: $185

expert-sleepers.co.uk