Attempt to summarize one part (the “playability”): You are suggesting the velocity curves and their interaction with the algorithms gave the DX7 a lot of its nuance?
Fine tuning with curves and offsets is what made DX programming an
art.
Think of a patch as a vector in the parameter space. For analogue
(subtractive/linear model) synthesisers almost all of the space makes
some kind of sense. You get a usable sound even if it's weird. With FM
(non-linear) synthesis a lot of the parameter space is completely
unusable and the great sounds are clustered in little islands around
which tiny changes in any parameters has wild effects - especially for
patches that use a feedback operator with high settings.
A good DX patch is a finely balanced creation. IIRC the sample rate is
60KHz and the oscillator control resolution is 14 bits, That doesn't
give you as much control as with digital virtual synths today. Setting
up fine control of key-tracking and velocity is absolutely essential
to making the DX preformative.
Now one of the lovely things is how you can download literally tens of
thousands of DX7 patches, all the Yamaha cartridges and compilations
of peoples personal patch collections from the past 40 years. But
because of the extreme sensitivity of the programming not all of them
work perfectly with the various emulator plugins and so they need
manual tweaking.
Interesting! I share a keen interest in synthesizers.
If you play these patches on the DX7 itself, how good is the reproducibility? I would assume the digital settings to match perfectly. Is there anything else going on that might make patches feel different on different DX7s?
For example, I could imagine some oscillators having subtle differences, perhaps with variation with temperature? If the signal path is all downstream of the same clock, at least until the final analog conversion, I’d expect negligible variation.
As far as I know the engineering standards within Yamaha are excellent
and consistent. From what I've heard DX9 patches sound perfect from
DX7 but without velocity, and TX7, TX816 and other modules sound
identical. Also DX7 patches import perfectly into later Yamaha FM
products.
About variance; I'm talking about the design of emulators. There's
quite a lot of VSTs and other plugins (that all sound amazing) but the
same patch doesn't necessarily sound identical on each. Two classic
voices to test from the original ROM presets are Tuberise and
GrandPNO2.
BTW these are digital oscillators so temperatures and component
tolerances are not a factor.
