Akashic Guitar effects circuit lookup
BOOSTTONEVOL

1590B · 3 knobs

Fuzz Dog· epicmod

EPically Modded Boost

Based on the Xotic EP Booster· 12 other boards clone it

Category
Boost
Controls
Boost · Tone · Vol
Difficulty
Medium
Price
£36.00
Tags
boost

From the vendor

For many years the EP Boost has been good and what it's meant to do - bring you 20dB of clean boost akin to the EP-3 tape echo pre-amp (apparently - anyone AB'd it?).

..and many years ago the legend that is Fred Briggs decided it could be improved upon. Here's our take on those improvements (detailed here) for your delectation.

An on-board charge pump gets you around 16V from your 9V supply, giving you lots of headroom for more cleans, even at max boost. The output is now pumped through a FET stage rather than the original BJT, again ensuring distortion is less likely. A master volume keeps things in check, and Mark Hammer's SWTC gives you treble bleed to calm your highs if you need to. The latter is very subtle, but it works.

The charge pump is optional - if you have a spare 18V output on your PSU then by all means feed it the pure Vs.

Available with through-hole or SMT FETs, so if you're capable of the fiddly little stuff then save yourself a few £.

If you want the PCB without parts there's a link for that at the bottom of the page.

Partial kit: PCB, all board-mounted components, pots.

Full kit: As above, plus footswitch and appropriate daughterboard/components for your selected bypass type (see Downloads section for details of those), jack sockets, DC socket, battery snap, hook-up wire, LED.

Enclosure (pre-drilled) is available as an option with full kits, and will not take a battery. Knobs are not included.

Inspired by: Briggs' Modded EP Boost

Difficulty: Medium

PCB size: 50 x 33mm

Knobs required: 3

Enclosure: 1590B

Direct-Connect compatible (4-way)

Download the INSTRUCTION PDF

Schematic

The schematic is in the vendor's build document, page 3. Open the build document. No KiCad fragment has been drawn for this circuit yet.

Parts list 32 rows

Report a wrong parse

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

RefValueNormalizedTypeNotes
Resistors 12
R11M1M
R233K33k
R31M1M
R44K74.7k
R5470R470
R61M1M
R73K33.3k
R81K1k
R9100R100
R1010K10k
R1110K10k
R13100R100
Capacitors 10
C147n47n
C210u10uElectrolytic capacitor
C310u10uElectrolytic capacitor
C410u10uElectrolytic capacitor
C510n10n
C610u10uElectrolytic capacitor
C15100u100uElectrolytic capacitor
C1610u10uElectrolytic capacitor
C1710u10uElectrolytic capacitor
C18100u100uElectrolytic capacitor
Diodes 3
D11N58171N5817
D41N41481N4148
D51N41481N4148
Transistors 2
Q12N5457/MMBF54572N5457 / MMBF5457
Q22N5457/MMBF54572N5457 / MMBF5457
ICs 1
IC2TL7660SEPA*TL7660SEPA
Potentiometers 3
BOOST10KCC10kPotentiometer
TONE10KBB10kPotentiometer
VOL100KBB100kPotentiometer
Trimmers 1
BIAS10K10k

Other boards based on the Xotic EP Booster