Enclosure not stated · 4 knobs

Xotic AC Booster

Based on the Xotic AC Booster· 3 other boards clone it

Category: Overdrive
Controls: Volume · Gain · Treble · Bass
Price: see vendor
Tags: freestompboxes.org trace

Read the post at Revolution Deux Schematic image Xotic AC Booster page

From the vendor

The Xotic AC Booster, a well-loved booster/overdrive. A 2SC1815 emitter-follower input buffer feeds a 4557 op-amp clipper with 1N4148 diodes in its feedback loop (two on one side, one on the other), and the less usual addition the post points out: an active Baxandall tone stack on the second half of the op-amp after the clipping, followed by a volume pot and a 2SC1815 output buffer.

Kusi's mods to turn the AC Booster into an RC Booster: C1 = 47n; C2 = 1u non-polar; remove R8 and bridge it; remove C4; R5 = 22K; R7 = 250K; clipping diodes 3x 1N4148 on each side.

Schematic

The schematic is in the post. Open it at Revolution Deux. No KiCad fragment has been drawn for this circuit yet.

Parts list 44 rows

Report a wrong parse

Got parts in a drawer? See what you can build with them.

Check before you build · 1 value the reader of this schematic was not sure of

The tone pots are not named on the drawing. R10 (between the 33n caps C7/C8) is listed as Bass and R11 (between the 4.7n caps C5/C6) as Treble, as in a standard Baxandall stack.

Ref	Value	Normalized	Type	Notes
Resistors 19
R1	1M	1M		read from the schematic by eye
R2	10K	10k		read from the schematic by eye
R3	1M	1M		read from the schematic by eye
R4	10K	10k		read from the schematic by eye
R5	10K	10k		read from the schematic by eye
R6	47K	47k		read from the schematic by eye
R8	10K	10k		read from the schematic by eye
R9	4.7K	4.7k		read from the schematic by eye
R12	33K	33k		read from the schematic by eye
R13	10K	10k		read from the schematic by eye
R14	4.7K	4.7k		read from the schematic by eye
R16	470K	470k		read from the schematic by eye
R17	10K	10k		read from the schematic by eye
R18	470	470		read from the schematic by eye
R19	100K	100k		read from the schematic by eye
R20	22K	22k		read from the schematic by eye
R21	6.8K	6.8k		read from the schematic by eye
R22	15K	15k		read from the schematic by eye
RLED	3.3K	3.3k		LED resistor; no designator drawn; read from the schematic by eye
Capacitors 14
C1	20n	20n		drawn 0.02uF; read from the schematic by eye
C2	100n	100n		read from the schematic by eye
C3	150p	150p		read from the schematic by eye
C4	100n	100n		read from the schematic by eye
C5	4.7n	4.7n		read from the schematic by eye
C6	4.7n	4.7n		read from the schematic by eye
C7	33n	33n		read from the schematic by eye
C8	33n	33n		read from the schematic by eye
C9	1u	1u		non-polar; read from the schematic by eye
C10	100n	100n		read from the schematic by eye
C11	10u	10u		electrolytic; read from the schematic by eye
C12	10u	10u		electrolytic; read from the schematic by eye
C13	10u	10u		electrolytic; read from the schematic by eye
CLED	2.2u	2.2u		electrolytic, across the LED; no designator drawn; read from the schematic by eye
Diodes 3
D1	1N4148	1N4148		read from the schematic by eye
D2	1N4148	1N4148		read from the schematic by eye
D3	1N4148	1N4148		read from the schematic by eye
Transistors 2
Q1	2SC1815	2SC1815		read from the schematic by eye
Q2	2SC1815	2SC1815		read from the schematic by eye
ICs 1
U1	4557	4557		drawn 4557D; read from the schematic by eye
Potentiometers 4
Volume	A100K	A100k	Potentiometer	R15; read from the schematic by eye
Gain	B500K	B500k	Potentiometer	R7; read from the schematic by eye
Treble	B50K	B50k	Potentiometer	R11; read from the schematic by eye
Bass	B50K	B50k	Potentiometer	R10; read from the schematic by eye
LEDs 1
LED	LED	LED		read from the schematic by eye

Other boards based on the Xotic AC Booster

Xotic AC Booster Dirtbox Layouts
AC Booster Guitar-Electronics.eu · €6.25
Xotic AC Booster Tagboard Effects