Author Topic: Vibrato organ pedal  (Read 1986 times)

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Vibrato organ pedal
« on: September 15, 2006, 08:08:43 AM »
Hi, does anyone know how to make a vibrato effect pedal for an organ that doesn't have vibrato?

Thanks

R.G.

Re: Vibrato organ pedal
« Reply #1 on: September 15, 2006, 10:39:12 AM »
A phaser or flanger with its final mix of the dry signal into the output disconnected is a vibrato.

This is the technique used in the univibe to change from chorus (actually phasing) to vibrato.
R.G.

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Re: Vibrato organ pedal
« Reply #2 on: September 15, 2006, 06:42:37 PM »
try doing a Patent search for Electronic Tremulant circuits ... although they all aim to achieve the "same" pitch-shifting purpose the specific way in which it's done will affect the quality of the effect ... some Ampeg Accordian amps like the 1958 435-S had a great sounding circuit based on variable frequency loading taking place through a rectifying bridge (somewhat similar to Don Bonham's Magnatone Varistor idea) - this one is the closest I've heard to a real Leslie ... I'm in the middle of doing jFET emulation of the 435-S using photocells as loaders and the Univibe LFO as driver ...

also, the first stage in the Resly-Tone and Jax Vibra-Chorus were used for a Tremulant option - so one stage of a Vibe photocell canceller will give you a simple version of that effect - tough, not that great sounding on account of the basic/gross way it cancels frequencies ... seems it's better if frequencies get split before then cancelled ... also, check out the Fender brownface Trem/Vib circuits for another version which does include some frequency splitting - likely jFET emulatable as well ...

~jc
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