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1590B · 3 knobs

Aion FX

CumulusVintage Overdrive

Based on the Ibanez OD-855· 1 other board clones it

Category
Overdrive
Controls
Drive · Tone · Volume
Difficulty
Easy
Price
$12.50in stock

From the vendor

An early overdrive circuit inspired by the Distortion+, but with the first appearance of the tone control that would later be used for the Tube Screamer.

The Cumulus Vintage Overdrive is based on the Ibanez OD-855 Overdrive II, a precursor to the Tube Screamer originally released in 1977. Like other Ibanez pedals, this one was designed by Maxon, whose name is on the original PCB and inside the enclosure, but this one was exclusively released under the Ibanez name.

With its diodes-to-ground clipping setup, the OD-855 actually has a little more in common with an MXR Distortion+ than with a Tube Screamer. It’s notable for being the first appearance of the classic Tube Screamer tone control— although in this case it appears before the clipping stage rather than after, and several values are changed so it doesn’t impact the same frequencies.

The Cumulus is a direct adaptation of the original OD-855, but with the JFET switching removed to convert it to true bypass. A clipping switch has also been added, so you can select between the stock clipping diodes and two other options.

The updated version of the Cumulus is the same as the earlier 1590B version except that the clipping switch has been modified to allow LEDs to be used in the center position as the third diode option.

Note: This project uses a type of capacitor that has been temporarily discontinued by WIMA. Please see our news article about the issue and the substitution spreadsheet for project-specific recommendations. We are stocking a limited supply in the mean time. The build document has not yet been updated to reflect this.

Schematic

The schematic is in the vendor's build document, page 6. Open the build document. No KiCad fragment has been drawn for this circuit yet.

Parts list 58 rows

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RefValueNormalizedTypeNotes
Resistors 20
R110k10kMetal film resistor, 1/4W
R2510k510kMetal film resistor, 1/4W
R33k3kMetal film resistor, 1/4W
R43k3kMetal film resistor, 1/4W
R5100k100kMetal film resistor, 1/4W
R6680R680Metal film resistor, 1/4W
R73k3kMetal film resistor, 1/4W
R810k10kMetal film resistor, 1/4W
R9100k100kMetal film resistor, 1/4W
R10470R470Metal film resistor, 1/4W
R1110k10kMetal film resistor, 1/4W
R12510k510kMetal film resistor, 1/4W
R1310k10kMetal film resistor, 1/4W
R14100R100Metal film resistor, 1/4W
R1510k10kMetal film resistor, 1/4W
R1610k10kMetal film resistor, 1/4W
R1710k10kMetal film resistor, 1/4W
R18100R100Metal film resistor, 1/4WPower supply filter resistor.
RPD2M22.2MMetal film resistor, 1/4WInput pulldown resistor.
LEDR4k74.7kMetal film resistor, 1/4WLED current-limiting resistor. Adjust value to change LED brightness.
Capacitors 14
C122n22nFilm capacitor, 7.2 x 2.5mm
C21uF1uFilm capacitor, 7.2 x 3.5mm
C3100n100nFilm capacitor, 7.2 x 2.5mm
C4470pF470pMLCC capacitor, NP0/C0G
C51uF1uFilm capacitor, 7.2 x 3.5mm
C6470n470nFilm capacitor, 7.2 x 3mm
C722pF22pMLCC capacitor, NP0/C0G
C91uF1uFilm capacitor, 7.2 x 3.5mm
C102n22.2nFilm capacitor, 7.2 x 2.5mm
C1147n47nFilm capacitor, 7.2 x 2.5mm
C131uF1uFilm capacitor, 7.2 x 3.5mm
C1447uF47uElectrolytic capacitor, 5mmReference voltage filter capacitor.
C15100uF100uElectrolytic capacitor, 6.3mmPower supply filter capacitor.
C16100n100nMLCC capacitor, X7RPower supply filter capacitor.
Diodes 7
D11N58171N5817Schottky diode, DO-41
D2GermaniumGERMANIUMGermanium diode, DO-7Any NOS germanium diode will work here. Can also substitute BAT41, a
D3GermaniumGERMANIUMGermanium diode, DO-7Schottky diode with similar forward voltage.
D41N9141N914Fast-switching diode, DO-35
D51N9141N914Fast-switching diode, DO-35
D61N9141N914Fast-switching diode, DO-35
D71N9141N914Fast-switching diode, DO-35
Transistors 2
Q12N50882N5088BJT transistor, NPN, TO-92Original uses 2SC1815.
Q22N50882N5088BJT transistor, NPN, TO-92Original uses 2SC1815.
ICs 1
IC1JRC4558DJRC4558DOperational amplifier, DIP-8
Potentiometers 3
DRIVE50kCC50k16mm right-angle PCB mount pot
TONE20kWW20k16mm right-angle PCB mount pot
VOL.10kBB10k16mm right-angle PCB mount pot
Switches 2
CLIPSPDT cntr offSPDT CNTR OFFToggle switch, SPDT on-off-on
FSW3PDT3PDTStomp switch, 3PDTAvailable from Aion FX.
LEDs 3
D83mm LED3MM LEDLED, 3mm, red diffused
D93mm LED3MM LEDLED, 3mm, red diffused
LED5mm5MMLED, 5mm, red diffused
Jacks & sockets 4
IC1-SDIP-8 socketDIP-8 SOCKETIC socket, DIP-8
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 mountLumberg NEB/J 21 C 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 Ibanez OD-855