Top octave dividers: A few ideas

Caloroso, Michael E CalorosoME at
Fri Nov 5 23:31:50 CET 1999

> This is the way that older organs worked, such as the Farfisa and Vox (actually,
> they usually used 13 oscillators - an additional oscillator was needed for the
> bottom C key, for some reason).
On the 49-key Vox, they had 12 voice cards each containing a HFO with three dividers that supplies frequencies for 48 notes.  The 13th voice card generated the bottom C for the 49th note.  This was the most economic way to to this, rather than fabricating an oddball voice card.  This was the way combo organs were designed before top octave dividers existed in compact form.  The Vox Continental was introduced in 1960.

> Even if the fixed frequency oscillators weren't perfectly temperature stable, the resulting sound might be more "lively" than a keyboard based on one master oscillator. Slight temperature variations would
> result in intervals that aren't perfectly in tune - but since equal temperment isn't perfectly in tune to begin with, the sound of this would probably be pretty nice.
Especially on the original Vox Continental with wood keys, where you could alter the pitch simply by holding an incandescent lamp over the voice cards  :)

Opinions (and mistakes) expressed herein are my own and not those of my employer.

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