Swirl O Vibe

Legendary unique chorus, vibrato, Leslie speaker, phaser effect

 

 

The Swirl O Vibe phaser rack effect module compares to the famous Univibe.  Swirling psychedelia for those who are experienced or need to get their Gilmour or Trower tones going.

 

Description

It's unclear whether Fumio Mieda of Shin-Ei was a super-genius or super-lucky.  He invented the Univibe, one of the more unique effects ever created.  It was apparently meant to sound like rotating Leslie speakers.  Regardless of how well it accomplished that goal, it became an instant hit as an effect in its own right.  At its core is a 4-stage phaser, with unusual capacitor values.  Normally in a phaser these capacitor values would all be the same, but his are all different - very different.  We don't know how Mieda picked their values, but they are magical.  No mathematical analysis explains it.  Change the values, or even the order of the capacitors, and it's just not the same.  The Univibe has been used by many players, including Jimi Hendrix, Robin Trower, and David Gilmour, to create fascinating, hypnotic tones in some of their most popular songs.

The Swirl O Vibe stays pretty close to the original circuit, adding only some minor options and changes.  The bulk of the changes come from using better components that cause less noise.  The critical lamp and photoresistor configuration has also been updated to modern components.  The tone of original pedals varied somewhat from one to another due to part tolerances, age of the lamp, and perhaps other factors.  The Swirl O Vibe may not sound identical to a specific original, but should get you into the range of Univibe tones.

 

Configurations

  • Swirl O Vibe - compares to Shin Ei Univibe and later derivatives such as the Fox Rox Aquavibe

 

Options

  • Swirl Trimmer - This option provides an internal trimmer that sort of tilts the phasing and affects the tone.  This is meant to be a set once trimmer.  Without a Swirl option, you get the standard Univibe phasing.
  • Swirl Control - Same as the Swirl Option, but gives you an external control for it.
  • Original Pull Down Resistor (PDR) - The Univibe has a small PDR that causes an impedance problem, which in turn results in a tone sucking loss of highs.  By default, we put in a larger PDR to prevent this, but that does brighten up the tone.  If you prefer the original PDR, select this option.
  • Impedance Switch - This option allows you to switch between the original low-value PDR and a higher-value PDR that prevents the tone sucking loss of highs. 
  • Chorus Only Mod - The Univibe has a Chorus/Vibrato switch.  We think the Chorus setting is where the tone lives and the Vibrato setting is a bit weak, but that's just an opinion.  If you want, we can hardwire the Swirl O Vibe to always be in Chorus mode and get rid of the Chorus/Vibrato switch.  Without this switch, you may be able to pick other options and stay within a 1.5" wide module.
  • Volume Control - The original circuit had an external volume control that allowed a volume cut (why?) or a small volume increase over the input level.  It doesn't seem that useful.  By default, we make this a trimmer inside the module, set for unity gain (same volume at input and output).  You can adjust it to some other volume if you prefer.  This is meant to be a set once trimmer.  Select this option if you want the Volume control like the original.
  • Blinking LED - Select this option to get an LED that blinks with the Speed.  This doesn't work as well with the Save My Bulb option.  With that option, the LED only blinks when the effect is engaged.
  • Save My Bulb Mod - There is a small light bulb at the heart of the circuit.  Like all light bulbs, it will eventually burn out and require a repair (it is soldered in place).  Normally, the bulb is on even when the effect is not engaged.  This probably decreases the life of the bulb.  If you prefer, we can turn off the bulb when the effect is not engaged.  Although we haven't noticed this, there is a theoretical side effect of switching the bulb with the effect.  It takes a little time for the bulb to get warmed up.  Until then, the bulb may produce a slightly different brightness, or brighten/darken at a different rate.  Since the bulb isn't left on all the time, it may not be warmed up when you turn the effect on, and the effect could sound a bit different, probably for a split second.  Again, we haven't noticed this, but it seems possible.
  • Carbon Comp Resistors - Go old school and switch from metal film to carbon comp resistors
  • Custom Components - We use metal film resistors and a selection of capacitors that provide good tone and low noise.

 

Front Panel

  • On/Off indicator LED
  • Speed
  • Intensity
  • Chorus / Vibrato switch
  • (optional) Volume control
  • (optional) Swirl control
  • (optional) Impedance switch
  • (optional) Blinking LED

 

Rear Panel

  • Audio In
  • Audio Out
  • On/Off Footswitch
  • On/Off Override
  • DC Power
  • DC Power LED

 

Module Width

  • 1.5" standard
  • 2" with options
  • 2" left wing and 1.5" right wing available for 2 - 4 control configurations.

 

Power Consumption (aprox)

31 - 35mA

 

Base Configurations

Part # Description List Price
MOD-SOVIBE Swirl O Vibe module $275

 

Options

Part # Description List Price
MOPT-SOVIBE-SWIRL Swirl Trimmer $0
MOPT-SOVIBE-POTSWIRL Swirl Control $19
MOPT-SOVIBE-OPDR Original PDR $0
MOPT-SOVIBE-SWIMP Impedance Switch $19
MOPT-SOVIBE-CHORUS Chorus Only Mod -$9
MOPT-SOVIBE-VOL Volume Control $19
MOPT-SOVIBE-LED Blinking LED $19
MOPT-SOVIBE-BULB Save My Bulb Mod $9
MOPT-SOVIBE-CCOMP Carbon Comp Resistors $10
MOPT-SOVIBE-CC Custom Components TBD