[sdiy] Re: [AH] Farfisa VIP organs

[Antti PitkXmXki]

>From: "JH." <jhaible at debitel.net>

>The dividers seem to be quite different from the Compact series.
>There, a frequency divider /2 is made of another oscillator roughly tuned 
>an
>octave lower, and sync'ed to the higher octave. I wonder what this means 
>for the vibrato,
>which is applied to the highest octave, and then propagated down from 
>oscillator to
>sync'ed oscillator. My first impression is that the lower octaves might be 
>modulated
>with a certain phase shift (speaking of the LFO modulation), compared to 
>the higher
>octaves. Is this true? Can anybody confirm this?

Hmm, I've got the schematics here... I think the vibrato oscillator only
modulates each of the 12 main oscillators. This, in theory, does make the
vibrato a more complex effect than just a vibrato, but how much it differs
from only a vibrato is another question. It sounds OK that's for sure. I can
send you the schematics if you want to check it out yourself.

The Farfisa Professional that came in 1968 didn't have a traditional vibrato
oscillator at all, but a phaser circuit designed to produce a weird vibrato
that sounds like a simple Leslie-emulator or a simple emulator of a
mechanical scanner vibrato. Because of the design, it was possible to set
the vibrato on/off independently on different sections. Not bad IMO but a
disappointment to those who want the basic cheesy vibrato.

Antti P.

_________________________________________________________________
Express yourself instantly with MSN Messenger! Download today it's FREE! 
http://messenger.msn.click-url.com/go/onm00200471ave/direct/01/