pitch-shifting stand alone vibrato unit

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tubeswell
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pitch-shifting stand alone vibrato unit

Post by tubeswell »

Finished this on the w/e. Its a 'pitch-shifting' vibrato unit that utilises a hammond saturable reactor (a triple transformer array from a hammond organ vibrato unit) and 2 x 12AU7, 2 x 12AX7 and a 12DW7. Designed to be plugged in front of a geetar amp (like a stand alone reverb). Its got 4 phase/pitch/harmonic controls, a feedback control output level/CF bypass and the trem oscillator controls. There is a switch on the front stage that bypasses the vibrato section to make the unit function as a tube booster. The output level is a dual-gang pot that turns up the recovery stage whilst mixing out the CF bypass or vice-versa.

Found a nice bit of scandinavian pine for the front of the box.

Scored the chassis 2nd-hand of Simcha Delft a wee while back and it cleaned up nicely with a wire brush.

Was a bit concerned about all the parts I was cramming in there but it didn't affect the sound ;-)

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Soundbytes attached FWIW

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Attachments
Reverb Unit and 5G9 clone.mp3
(1.21 MiB) Downloaded 155 times
Viberator in the sky.mp3
(631.76 KiB) Downloaded 710 times
Surf Buggy Vibe.mp3
(678.29 KiB) Downloaded 623 times
Last edited by tubeswell on Sat Mar 03, 2012 5:07 pm, edited 1 time in total.
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pitch-shifting stand alone vibrato unit

Post by sizzlingbadger »

Very cool indeed...
Tube amp and guitar tones straight from 1958… amazing how believable the sounds were back then, even without the modellers...

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Re: pitch-shifting stand alone vibrato unit

Post by alanp »

That sounds amazing. How well would it go with some kind of expression pedal?
Capt. Black wrote:Call me if you're looking for the sound of a sows ear made from a silk purse with a side of hot bitches and alcohol

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Re: pitch-shifting stand alone vibrato unit

Post by robnobcorncob »

Excellent work as always Pete!

tubeswell
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Re: pitch-shifting stand alone vibrato unit

Post by tubeswell »

Some more technically recorded soundbytes with me accompanying myself on my AVRI JM using this rig (with the vibrato unit cab now stained).

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The amp in the rig is a ~22W fixed-bias PP6V6 using Merlin Blencowe's EF86 morph control in the pre, and is powered by a Weber Sig 12 (smooth cone). The gingham thing is a 6G15 reverb unit clony thing. The extn cab has a Greenback G12M I got off Ryan a while back. Both cabs are mic'd with SM57s through my desk and into garbageband. Excuse the crappy playing as usual.

http://music-electronics-forum.com/atta ... rater-.mp3
http://music-electronics-forum.com/atta ... rater-.mp3
http://music-electronics-forum.com/atta ... rater-.mp3
He who dies with the most toobs... wins

tubeswell
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Re: pitch-shifting stand alone vibrato unit

Post by tubeswell »

Went back and did the signal ground elevation trick in this today - now it don't hum anymore
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