I attended both Superbooth in Berlin and Knobcon in Chicago this year, and both were very modular-centric. They were brimming with Eurorack (and some 5U) makers both nascent and established, both large and small, and one thing struck me: In spite of the incredible diversity of modules and design philosophies on display, this seemingly chaotic community had it more together about standardized terms than what we might call the more traditional electronic keyboard industry.
I refer to the fact that different manufacturers sometimes use different words to refer to what are essentially the same operating modes, parameters, and categories of instruments. At the root of the phenomenon is the mandate of branding. Branding is not in itself bad; it’s natural and usually necessary for a brand to distinguish itself from its competitors in ways that are concise and easy to understand. In ten years of being an editor at Keyboard magazine (seven of those as editor in chief) and about the same amount of time doing freelance writing on both the journalistic and marketing sides of the business, I also came to understand that manufacturers want to preach to someone other than the in-the-know enthusiasts who form the choir. They want to communicate a holistic music-making experience to newcomers, and they want to do so in language they see as more benefits-based and less technical.
But when marketing departments stray too far from touting the benefits of their product versus their competitors’ and instead tread into co-opting and changing words that should merely be descriptive and instructive, those newcomers get confused. As for the enthusiasts and the initiated, keyboard players have something of a consensus about vocabulary and it’s bigger than any one company. I don’t mean to be churlish — over the years I’ve reviewed every major manufacturer's products, gigged with them, recorded with them, and loved many of them. So I won’t call anyone out.
What I will do is offer my from-the-hip glossary of what I take that consensus to be. I actually care less about which words we choose than about us all being on the same page, and I recognize that no vocabulary is static. But enough with the disclaimers …
A single group of settings (usually saved with a name or at least a number) meant to create a single type of instrument sound is a patch, which originated with patching modular synths. Program is also fine.
A multi-timbral combination of patches or programs meant to stack sounds or assign them to different places on the keyboard is a multi or maybe a combi. (Performance, on the other hand, is what a human being is supposed to do with an instrument.)
Multi-timbral means something can play more than one patch (on different MIDI channels) at the same time. The standard is up to 16 at once. I don’t like polytimbral because of the possible confusion with polyphony.
A voice is a single audio stream or synthesis signal chain (such as oscillator to filter to envelope) within a patch. It’s also a unit of polyphony. Though a different sense of voice - synonymous with patch or program - does have a legitimate history in organ terminology.
Polyphony should almost always be measured in voices, not notes. If a single patch on a 128-voice sampling synth uses two voices all the time, then you’d in fact get 64 notes of polyphony. In sample-based synths, stereo sampling normally doubles the voice usage, so patch that used two stereo voices constantly would net you 32 notes.
Exception to the above 1: Patches in sample-based synths might not use all their voices all the time and might be good at re-allocating them, e.g. using a voice for the attack of a piano, which then becomes available again as soon as that attack dies out.
Exception to the above 2: Many analog synths play the same number of notes regardless of whether the patch uses one, two, or more oscillators.
Exception to that exception: Some analog synths (famously the Korg Mono/Poly) have a choice of voice assignment modes, offering a give-and-take between oscillators per note and notes played at once.
By the way, analog means the thing is actually using analog circuitry to generate sound, not just that it has lots of knobs and sounds "retro." A synth like this with digital (or software) guts must be clarified as virtual analog.
To be called a synthesizer, it’s not enough that a keyboard can imitate a variety of preset instrument sounds. It has to let you get inside the sound and edit deep aspects of it such as waveforms, filtering, the mix of oscillators, and modulation via things like LFOs and envelopes. Just having something like tone control and basic vibrato doesn’t go deep enough to warrant the term either.
Only a keyboard that has a multi-timbral onboard MIDI sequencer/recorder (and maybe audio recording as some do), and thus lets you create a complete musical production without any other gear besides your speakers or headphones, can be called a workstation.
Any keyboard that (A) plays automatic accompaniment selected by names of various musical genres, (B) does so with multi-instrumental parts, not just drum patterns, and (C) follows your left-hand chord changes via either full fingering or some sort of easy-play shortcut, is an arranger.
An arranger workstation combines the features of an arranger and a workstation.
A digital piano is a keyboard primarily focused on acoustic and electric piano sounds, with at least 73 or 76 but usually 88 keys, and they’re usually weighted. It might also have other good sounds. Stage pianos are a subset focused on portability, and therefore usually lack the built-in speakers of their home-dwelling counterparts.
A drawbar organ intended chiefly to create the sound of vintage tonewheel organs (which used a rack of spinning metal discs next to pickups to generate sound), but that uses any other, more modern means to do so, is a clonewheel. The term has no derogatory connotations, though simply saying "organ" might communicate more effectively with, say, the church market.
This is neither a complete nor perfect list, there are instruments that overlap categories, and so on. But within this framework or something like it, there’s still plenty of room for brands to distinguish their [insert type of keyboard here] from their competition, but with additional clarity that I think customers will ultimately reward. Now wasn't that easy?