Seldom has a new synth from a new company excited so much anticipation as the Hydrasynth. Should you believe the hype?
One of the highlights of SynthFest 2019 was the opportunity to get hands-on with the ASM Hydrasynth — and I wasn't the only old-timer gushing about the return of ribbons and polyphonic aftertouch. Afterwards, the long winter months dragged on endlessly, but finally one arrived at my studio. Two, in fact, because the Hydrasynth Desktop was released at the same time.
To understand some of the excitement, it's worth stepping back and pondering what makes polyphonic aftertouch so enduringly fascinating. Whenever the topic arises, there's almost always mention of a certain classic synthesizer. In the 1970s, many of us lusted over that instrument despite the fact that it was impractical for any bedroom studio, even if a rich aunt died and bequeathed the necessary dosh.
I'm talking about the Yamaha CS‑80, of course. This mighty instrument, in the hands of virtuosos such as Vangelis, proved that synthesizers really could be responsive, expressive musical instruments after all.
Polyphonic aftertouch, or poly pressure, allows the player to modulate notes individually from within a range already held down. This requires sensors for every key and is therefore more complex to produce than channel or mono aftertouch. Typically based on a strip beneath the keyboard delivering a single value to the whole synth, channel aftertouch is ideal for monophonic instruments but less effective when applied to a whole chord. This is where the CS‑80 — and just a handful of other synths — score so highly.
Ashun Sound Machines are a new Chinese company determined to tackle the expression deficit. Their polyphonic pressure implementation is pretty thorough, and includes user tailoring of parameters such as delay, onset time, fade and release, to reduce bounce, jitter and so on. The Hydrasynth response should therefore be adaptable for most players.
The four-octave keyboard feels great. I particularly like the squared-off black notes, which lend it a more piano-like feel and assurance. You can choose from a selection of velocity and aftertouch curves, but there's no denying it lacks the fifth octave regarded as essential by most two-handed players.
Length issues aside, you'll be pleased to hear that the Hydrasynth is not just an expressive controller with any old synth engine tacked on. It is a digital eight-note polyphonic instrument with three analogue modelling oscillators, two of which can perform 'waveform scanning'. These are ably assisted by two filters, five LFOs, five envelopes, an arpeggiator, multiple effects and a comprehensive 32-slot modulation matrix! It's a monotimbral experience, though, with no layering or split capabilities.
These are substantial instruments, weighing in at 10kg and 3.6kg respectively, with no skimping on I/O. MIDI is available over USB and a full complement of 5-pin ports. The keyboard model has a ribbon controller running almost its full length, and on both versions, every knob, button and encoder feels solid and trustworthy.
A chunky encoder is the gateway to selection from the five banks of 128 patches available. Each patch has its own colour, which is reflected in the encoder and left-hand controls. On shipping, only banks A-C are populated, but ASM offer a further bank on their web site, plus manager software to move data around, make backups and so on. This might be worth exploring sooner rather than later, because the synth always powers up at Bank A's first patch, while your own will probably begin in the empty Banks D and E.
Getting around isn't as easy as it might be because there's no method of going directly to a particular location. Initially, you change patches by spinning the encoder or pressing the L/R arrows, holding Shift to jump in 10s. To speed things along you can define 32 'Favorite' patches which serve as more efficient entry points. Additionally, you can browse by name and category, but there are no User categories.
It's hardly surprising that the Hydrasynth's factory patches set the scene with some impressive Vangelis tones, paying particular homage to the Blade Runner score. Scrolling on, you'll encounter usable brass, strings, bells, basses and arpeggios — sounds that wouldn't seem out of place on a synth from the 1990s. I was most taken by the wavetable sweeps, glassy digital textures, pads and electric pianos, many demonstrating the excellent reverb. While there are a host of worthy bread-and-butter patches, very few give a sense of how strange and 'out there' the Hydrasynth can be.
Let's face it, if the Hydrasynth had a control for every parameter, few of us could afford one. Instead, the main interface is built around encoders, buttons and a crispy clear OLED display. A second display provides patch names, envelope and waveform graphics and an oscilloscope that reflects the real-time output. The architecture is represented as an interactive panel of 26 Module buttons, each an entry point for further pages. Repeatedly pressing a button progresses through the pages, and there are dedicated page buttons too. Further visual assistance is provided by the dynamic lighting of the LFO and...