This is a tough one to stick with the analogy and remain in the realm of useful audio processing. Not that it's a bad idea. I love the metaphorical approach as an inspiration / challenge. There is the aesthetic/subjective interpretation of the adjectives and the technical one, which sometimes differ.
-
"wet", to me, means reverbation/delay. "clean", to me, means less "noise".
-
"dry", to me, means lacking in reverbation/delay. "crisp", to me, means boosted higher frequencies and maybe also attenuated lower frequencies.
-
"fold" does immediately make me think of wave folding, yeah. I guess if you thought of it as a way to prepare the sound to be "put away" or "stored", if could be lossless encoding too. haha. It could also be some concept of smaller pieces of the original sound (the loose concept of "folding time"), like some kind of creative delay that plays back little chunks of past input in some interesting way that isn't just a plain old delay.
Obviously, these stages kind of contradict themselves logically as a real time process, but that's ok. It's not like you'll get the exact same thing on the output if you set everything right (Unless we're elite DSP masters. lol). Would it necessarily be hardwired with one input and one output like > Wash > Dry > Fold >? Might be more flexibility in design it was like
> Wash >
> Dry >
> Fold >