I admit I have never played a real clavinet.
But my understanding is that the clavinet model should support aftertouch, much like Pianoteq's historical clavichord models.
Is aftertouch missing from the Pianoteq clavinet? Or is my understanding incorrect?
Real clavinet doesn't have aftertouch action - it doesn't behave like historical clavichords.
You can add aftertouch to it in Pianoteq, though, by editing the aftertouch curve...
I see I got the idea from Andrew Stiller's "Handbook of Instrumentation" (1985) -- an amazing and practically flawless book:
"Because the fingers are in direct mechanical connection with the strings throughout the duration of each note, the clavinet is the most expressive of the modern keyboards. By varying the pressure on the key *after* the note is struck, it is possible to produce a delicate vibrato, or bent tones up to a quarter-tone above the pitch initially sounded. The vibrato is ineffective in chords and is best applied to single melodic lines."
I've owned a Hohner Clavinet D6 for about the last 20 years.
It doesn't really have aftertouch in the way that paragraph describes -
when you press a key down (and rather lightweight plastic key), you are pressing a little rubber (neoprene) hammer-head down onto the string, pinching it against a rigid brass (fret? anvil? - not sure what to call it).
In the lower registers, you can (slightly) feel string vibrating through the plastic key (which is nice, I guess, but doesn't make it sound any different). You can't vibrato the pitch, though - as you cannot move the key side to side. You can kinda squidge the key slightly (compressing the rubber hammer more) but that doesn't really do anything to the sound. If you ease the key off really slowly, the string just might do a little bit of fret buzz then stops sounding. (Each key has a spring that makes it naturally want to come off the string).