Aion Electronics Refractor Overdrive Manual

Refractor Overdrive
Klon Centaur Professional Overdrive

Overview

Controls & Usage
Standard overdrive controls on this one.
• Treble control allows for EQ adjustment of the top end.
• Output is the overall effect volume.
• Gain simultaneously increases the gain and blends from clean signal to dirty using a dual pot.
Modifications & Experimentation
No built-in mods for this one, but there are a few part substitutions you can experiment with.
Tone capacitor mod: A very common and well-regarded modification is to change C14 to either 6n8 or 8n2. It
fixes a complaint of Centaur clones that the treble is a little thin, and nearly everyone who's done it says it's a
huge improvement.
Socket the diodes. The original uses germanium diodes with a forward voltage of around 0.35v, but others
have reported good sounds from BAT41, OA126 or even the plain old 1N914.
Socket the op amps as well. The original uses TL072s, but many people have reported good things from
mixing these up, such as an LF353 or JRC4558D for IC1 and a NE5532 for IC2.
Bass guitar mod: Use a 390n film capacitor for C1 if you're going to use it as an overdrive for bass.
KLON CENTAUR / REFRACTOR OVERDRIVE
The Refractor is a part-for-part replica of the legendary Klon
Centaur Professional Overdrive. The Centaur is a really
unique overdrive pedal, an original design not based on a
Tube Screamer or Big Muff like a lot of other "innovations"
in the past 20 years. This project was designed to fit into a
1590B, so it's a great deal smaller even than the KTR (the
"miniaturized" reissue of the Centaur).
The Centaur's switch wiring is pretty cumbersome. Check out
the Refractor Bypass PCB
New version 2: The Refractor has been redesigned for a
more optimized layout. Power and signal ground have been
separated (see new wiring diagram on page 7) which should
theoretically cut down on noise. The diodes have been
given more space, and best of all, there are no more 1/8w or
standing resistors!
The part numbering is identical, and the drilling template is
the same except that the LED moved up about an eighth of
an inch and the Gain and Tone knobs swapped places.
Refractor Project Link
for an easy solution.
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