[sdiy] Analog polyphony question

[Glen]

Dr Strangelove wrote:

> Actually I had said that the Vox Jaguar does something different.  I meant
> the Vox Continental (hmm, this sounds like some sort of suspicious
> backpeddling to save face).  It uses high frequency Hartley Oscillators
> (Signal tapped from a split inductance in a resonant circuit), and a strange
> sort of divider circuit to derive the lower octaves.  The wierd thing about
> it is that I think it outputs something besides square waves, The Jaguar
> sounds like square waves though.....  Kinda like a beefed up thomas organ
> but with a vox vibrato.  I've heard both of them, in, errrr, samples I've
> tracked with  :-).

I happen to have a Vox Super-Continental. I can definitely confirm that this
particular model has 12 high frequency oscillators, and uses divider circuitry
to generate the lower pitches from those 12 reference pitches. I  can't verify
the type of divider circuitry, except that I don't believe there are IC's in
this organ. I also can't verify what types of waveforms are generated, at least
not from memory.

However, I can confirm that this model has both "bright" and "dark" drawbars
(refers to tonal properties, not appearance.) Also, don't forget that this organ
has "mixture" drawbars - something that a Hammond didn't have. These will
definitely not be producing a simple square wave with each note played, although
they might indeed be derived from square waves, for all I know.

I'm not at home, so I don't have access to the organ at this moment. If anyone
seems interested, I'll try and confirm more details about the circuitry in a day
or two.

As for Thomas organs, which model are you referring to? Thomas made a *lot* of
different organs, and there was a wide variety of sound qualities and circuit
designs represented during their history.


Later,
Glen