Akashic Guitar effects PCB lookup
EXPANDERVOLUMETONE

125B · 3 knobs

Aion FX

RiftOctave Fuzz

Based on the Univox Superfuzz· 4 other boards clone it

Category
Fuzz· Octave Fuzz
Controls
Expander · Volume · Tone
Difficulty
Intermediate
Price
$12.50in stock

From the vendor

A classic untamed fuzz from the 1970s that adds an octave-up overtone, famous for its use by Pete Townshend of The Who.

The Rift Octave Fuzz is a recreation of the Univox Superfuzz, originally developed by the Shin-ei company in Japan in the late 1960s and called the FY-6. Shin-ei rebadged the circuit for over a dozen other brands such as Apollo, Electra and Hohner. However, the Univox Superfuzz was the most well-known of the brands and today is considered the definitive version of the circuit.

The Superfuzz uses a phase splitter followed by a differential pair to emphasize the upper octave. It’s very similar in concept to something like the fOXX Tone Machine, but with the major difference of using active transistors instead of diodes to rectify the signal.

The Rift includes one modification to lend more flexibility to the circuit. While the original unit only had a tone switch to go between two presets, this project provides the option of using a potentiometer to blend between them so it’s not just full-on one way or the other.

The new 125B version of the Rift is identical to the previous one, except that the diode clipping switch has been removed in favor of a simpler layout that is easier to build. The previous version of the Rift is still available if you want that option.

Schematic

The schematic is in the vendor's build document. Open the build document. No KiCad fragment has been drawn for this circuit yet.

Parts list 68 rows

Report a wrong parse
RefValueNormalizedTypeNotes
Resistors 32
R122k22kMetal film resistor, 1/4WFY-6 uses 100k here.
R2100k100kMetal film resistor, 1/4W
R3100k100kMetal film resistor, 1/4W
R41k81.8kMetal film resistor, 1/4W
R547k47kMetal film resistor, 1/4W
R6470k470kMetal film resistor, 1/4W
R710k10kMetal film resistor, 1/4W
R847k47kMetal film resistor, 1/4W
R93k33.3kMetal film resistor, 1/4WFY-6 uses a jumper here.
R10220k220kMetal film resistor, 1/4W
R11150k150kMetal film resistor, 1/4W
R1210k10kMetal film resistor, 1/4W
R1310k10kMetal film resistor, 1/4W
R14470R470Metal film resistor, 1/4W
R15470R470Metal film resistor, 1/4W
R16100k100kMetal film resistor, 1/4W
R1722k22kMetal film resistor, 1/4W
R1810k10kMetal film resistor, 1/4W
R191k81.8kMetal film resistor, 1/4WFY-6 uses 2k here.
R2022k22kMetal film resistor, 1/4W
R21100k100kMetal film resistor, 1/4W
R2247k47kMetal film resistor, 1/4W
R2310k10kMetal film resistor, 1/4W
R2422k22kMetal film resistor, 1/4W
R2510k10kMetal film resistor, 1/4W
R26100k100kMetal film resistor, 1/4W
R2715k15kMetal film resistor, 1/4W
R2810k10kMetal film resistor, 1/4W
R291k1kMetal film resistor, 1/4W
R30100k100kMetal film resistor, 1/4W
RPD2M22.2MMetal film resistor, 1/4WInput pulldown resistor. Can be as low as 1M.
LEDR10k10kMetal film resistor, 1/4WLED current-limiting resistor. Adjust value to change LED brightness.
Capacitors 17
C110uF10uElectrolytic capacitor, 5mm
C22n22.2nFilm capacitor, 7.2 x 2.5mmFY-6 uses 1n here.
C310uF10uElectrolytic capacitor, 5mm
C4100n100nFilm capacitor, 7.2 x 2.5mm
C510uF10uElectrolytic capacitor, 5mm
C610uF10uElectrolytic capacitor, 5mm
C710uF10uElectrolytic capacitor, 5mm
C810uF10uElectrolytic capacitor, 5mm
C910uF10uElectrolytic capacitor, 5mm
C1010uF10uElectrolytic capacitor, 5mm
C1110uF10uElectrolytic capacitor, 5mm
C121n1nFilm capacitor, 7.2 x 2.5mm
C13100n100nFilm capacitor, 7.2 x 2.5mm
C1410uF10uElectrolytic capacitor, 5mm
C1510uF10uElectrolytic capacitor, 5mm
C16100uF100uElectrolytic capacitor, 6.3mmPower supply filter capacitor.
C17100n100nMLCC capacitor, X7RPower supply filter capacitor.
Diodes 3
D11N58171N5817Schottky diode, DO-41
D31N34A1N34ADiode, germanium, NOSCan also use BAT41.
D41N34A1N34ADiode, germanium, NOSCan also use BAT41.
Transistors 6
Q12N39042N3904BJT transistor, NPN, TO-92Substitute. Original uses 2SC828, 2SC537, or 2SC539.
Q22N39042N3904BJT transistor, NPN, TO-92Recommended to use 2N3904 (higher gain) for Q1-3 and 2N3903 (lower gain) for Q4-6.
Q32N39042N3904BJT transistor, NPN, TO-92Also recommended to match Q4 and Q5 as closely as possible.
Q42N39032N3903BJT transistor, NPN, TO-92
Q52N39032N3903BJT transistor, NPN, TO-92
Q62N39032N3903BJT transistor, NPN, TO-92
Potentiometers 2
BAL50kBB50k16mm right-angle PCB mount pot
TONE50kBB50k16mm right-angle PCB mount potOptional modification - can use a potentiometer instead of a switch to blend between tone settings.
Switches 2
TONESPDTSPDTToggle switch, SPDT on-onOmit if using tone pot.
FSW3PDT3PDTStomp switch, 3PDT
LEDs 1
LED5mm5MMLED, 5mm, red diffused
Jacks & sockets 3
IN1/4" stereo1/4" STEREO1/4" phone jack, closed frameSwitchcraft 112BX or equivalent.
OUT1/4" mono1/4" MONO1/4" phone jack, closed frameSwitchcraft 111X or equivalent.
DC2.1mm2.1MMDC jack, 2.1mm panel mountMouser 163-4302-E or equivalent.
Hardware 2
BATTBattery snapBATTERY SNAP9V battery snapOptional. Use the soft plastic type—the hard-shell type will not fit.
ENC125B125BEnclosure, die-cast aluminumCan also use a Hammond 1590N1.

Other boards based on the Univox Superfuzz