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'Cheapo' Univibe alternative?

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2/25/2000 9:56 AM
Chris	'Cheapo' Univibe alternative? Just a thought. Since the basis of the univibe effect seems to be a combination of amplitude modulation (ie., tremolo) and phasing, what about running a decent phaser (say a Phase 90) into a 'soft' sounding trem? Has anybody tried this and if so, how faithful a 'vibe-like reproduction was it? Many thanks, Chris

2/25/2000 11:59 AM
Tobias Karlsson	I've tried to use the "vibes" phase caps in my PH90 style phaser. I don't think the result sounded more like the "Vibe". It made it sound like a week and more moving the higher freq. up and down, almost like twisting the 7khz knob on an eq. It would be VERY interesting to know why. I thought I had figured out a really clever mod, but aperently not.... Tobias Karlsson in Sweden

2/25/2000 1:59 PM
Chris	Thanks for the feedback Tobias.

2/25/2000 3:57 PM
GFR	At http://www.lynx.bc.ca/~jc/ look for Mod : Univibing the Electro-Harmonix Small-Stone ('97)

2/25/2000 4:19 PM
Chris	Thanks GFR, but I'm not too good with a soldering iron! Would the combination of pedals I mentioned get me ANYWHERE close? Thanks

2/26/2000 10:12 AM

Re: 'Cheapo' Univibe- its a phaser

Combining two pedals in this manner still requires at least some soldering - you'll want the LFO's to run the same speed, or better yet, use only one of them. And what this 'll do.... it *might* approximate a Leslie, but it also might sound kinda strange.
The Uni IS just a phaser after all, it's not a leslie cabinet! I don't see how a Uni (compared to, say, a Phase90) does amplitude modulation, except for percieved modulation, due to shifts in frequency content.
The unique sound of a Uni has more to do with the way it's built, and it's faults (slight distortion, etc)
Correct me if I'm wrong here guys!

2/27/2000 10:37 PM

DOD Phasor 201!

I think one of the keys to a Univibe's tone is its lopsided LFO sweep -- it's definitely not a textbook sine wave. I've never really studied how a Uni works, but it seems like the shape of the LFO is determined by how long it takes a little light bulb to light and then dim with each pulse, so you end up with real asymmetrical pulses.

The newer DOD and Boss phasers sound too mechanical and fake because their LFO circuit is too good -- they spit out too nice of a sine wave. Most multi-effects units are the same way.

I've got an old, gray, cast-metal DOD Phasor 201 that does a surprisingly good Univibe imitation. It's got a nice fat voice and beautifully lopsided pulses. Since I've owned it, I've come across two more Phasor 201's -- a slightly later model with a yellow housing and a modern reissue of the yellow model. Neither was nearly as good as my grey one, so maybe they changed something when they went to the yellow.

But that's my recommendation for a cheap Univibe alternative: a grey DOD Phasor 201. The other thing that's nice is that it's really small and compact -- roughly the size of a Phase 90.

Michael Tousek

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