does the sansvalve need matched MOSFETs? i see that gez used a CD4007 for his nut cruncher and that gives nicely matched pairs. but given that asymmetry introduced by a resistor is interesting, it seems possible that "odd couples" might be a good thing too.
ton, you just grabbed a pair out of the pile for your experiments, right?
yep, the "Nutcruncher" doesn`t count here, because it`s not discrete

(

);
upon jaytee`s request in reply#10, I tried a lot of combinations of all (~30) mosfets of the named types (170/250) I had at hand,
as noted in reply #16.
The (small) variations in the established bias
was audible and visible,
but close enough to be acceptable for the usual circuits, and especially for a "trimmerless-field-effect-stage"
(that very first breadboard test was a completely "blind" test, but perfect).
Gotta keep in mind, though, that it`ll always be a "classA/B" configuration, with a potential for crossoverdistortion (

).
Back to your question:
it obviously doesn`t need matched components (for the types used), and no adjustments.
(which is the fact I loved about the hex-inverters, and always thought is immanent only to
them...).
It seems that the manufacturers are able to produce tight V
t tolerances in these devices nowadays;
and the use of those "inline"-resistors, that increase ("linearize") the resistance of the voltage-divider (Rds
P/Rds
N)
which in fact establishes the bias fromout its center-node, seems to add to the symmetry (me thinks)...