[sdiy] Tubes in Synths [ was : Harry's Nightmare! ]

[jh.]

> Yes, except that in a phase shifter (such as the Magnatone or the Univibe)
> the top and bottom loads are different.

You're right. Collector sees LDR + C, emitter sees LDR + C + Rc.
But then again this is all inside a positive (!) feedback loop, so
you cannot simply ground the "other end" for analysis. It's
tricky ...

> (I suppose a spice simulation would be the right thing about now.  :-))

Did it back then for the Neptune (based on Univibe). There is a slight
gain error. I haven't explored if it's from the loading or from
the limited gain of a transitor, however. But it was much worse for
a tube.

JH.