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GAIA PREAMP DRIVE MK. I

1

PROJECT NAME

GAIA MK. I

BASED ON

EFFECT TYPE

PROJECT SUMMARY

DOCUMENT VERSION

Catalinbread

®

 CB30

An adaptation of the Vox

®

 AC30, a legendary British amplifier responsible for the signature guitar tones 

of the 60s and 70s. It uses cascaded mu-amp stages in place of tubes for amp-like tone in a small box.

Overdrive / Amp Emulation

1.0.0 (2021-05-28)

Actual size is 2.3” x 2.42” (main board) and 1.78” x 0.87” (bypass board).

BUILD DIFFICULTY

Intermediate

This documentation is for the 

Mk. I

 version of the project. There is also a 

Mk. II

 version, based on 

the Galileo. While the name is similar, the circuit and part numbering are different. Please be sure 
your PCB is labeled “Gaia Mk. I” before proceeding with this build document.

IMPORTANT NOTE

Summary of Contents for GAIA MK. I

Page 1: ...in place of tubes for amp like tone in a small box Overdrive Amp Emulation 1 0 0 2021 05 28 Actual size is 2 3 x 2 42 main board and 1 78 x 0 87 bypass board BUILD DIFFICULTY Intermediate This docume...

Page 2: ...457 JFETs which are no longer available in through hole format Extra pads have been provided if you want to use surface mount JFETs part number MMBF5457 which perform identically to those used in Cata...

Page 3: ...al film resistor 1 4W R10 2M2 Metal film resistor 1 4W R11 390R Metal film resistor 1 4W R12 1M Metal film resistor 1 4W R13 1M Metal film resistor 1 4W R14 100k Metal film resistor 1 4W R15 12k Metal...

Page 4: ...ytic capacitor 4mm C19 1uF Electrolytic capacitor 4mm C20 2n2 Film capacitor 7 2 x 2 5mm C21 1uF Film capacitor 7 2 x 3 5mm C22 22uF Electrolytic capacitor 5mm C23 2 2uF Electrolytic capacitor 4mm C24...

Page 5: ...e PCB mount pot BASS 1MA 16mm right angle PCB mount pot TREBLE 1MA 16mm right angle PCB mount pot VOL 100kA 16mm right angle PCB mount pot IN 1 4 mono 1 4 phone jack closed frame Switchcraft 112BX or...

Page 6: ...heet for a given part number will usually show an enormous range for crucial specifications such as VGS off and IDSS However in practice parts from the same manufacturer are usually much tighter in sp...

Page 7: ...22n 1MA GND 470k 1uF 470k 2M2 2N5457 GND 390R 47uF GND GND 2N5457 1M 1M VA GND VA 2 2uF 1uF 2n2 VA 470k 1uF 470k 3M3 2N5457 GND 1k 22uF GND GND 2N5457 1M 1M VA GND VA 2 2uF 2 2uF 1n VA 2u2 GND 100R 1...

Page 8: ...of closed frame jacks like the Switchcraft 111X If you d rather use open frame jacks please refer to the Open Frame Jack Drill Template for the top side LED hole drill size assumes the use of a 5mm LE...

Page 9: ...GAIA PREAMP DRIVE MK I 9 ENCLOSURE LAYOUT Enclosure is shown without jacks See next page for jack layout and wiring 125B...

Page 10: ...GAIA PREAMP DRIVE MK I 10 WIRING DIAGRAM 125B IN V GND NC NC OUT PCB IN GND V V JACK GND JACK OUT IN GND GND PCB OUT...

Page 11: ...as suggestions based on the experience and opinions of others Projects may be used for commercial endeavors in any quantity unless specifically noted No attribution is necessary though a link back is...

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