Akashic Guitar effects circuit lookup
RATIOTONEATTACKLEVELRELEASESUSTAIN

125B · 6 knobs

PCB Guitar Mania

Tone Guard Device

Based on the EarthQuaker Devices The Warden· 6 other boards clone it

Category
Compressor· Optical Compressor
Controls
Ratio · Tone · Attack · Level · Release · Sustain
Difficulty
Average
Price
€11.90out of stock

Heads up Builders widely report inconsistent quality from PCB Guitar Mania boards, and whether a given board works is a gamble. Read recent forum reports before ordering.

From the vendor

Project overview

High-fidelity Optical compressor based on Earthquaker Devices ‘The Warden’ Features an internal charge pump to give your tone plenty of headroom.

Introduction

The tone keeper is a six-knob optical compressor based around the EQD Warden and lifts every slightly hit note right into your face. A compressor with so many features usually reserved for studio gear and work equally well on bass guitar. A built-in charge pump brings the unit up to 18v while you only need 9v to power it but still get the maximum clean headroom and sustain without getting noisy at all, thanks to the opa2134. (This chip is a bit more expensive, but I really recommend it every time you want to make a build less noise – for instance, the ace had great results in my personal BE-OD.)

If you want to try your build first and order that chip later from a trusted source, you can replace it with a TL072 – but keep in mind, backgrounders noise will increase by doing that.

But let’s get back to the topic: tone, attack, release, level, sustain, and ratio gives you every control in your hand you could need to get the maximum out of every note. For tweaking a compressor the first time, start with all knob at noon and adjust from there while switching the pedal on and off from time to time so your ears get a better chance to hear the difference. Led is a clear white, no. Red to angle it, I had around 2-3mm distance to the LDR that faces the led’s direction. You can use sockets if you want to try different LEDs but keep in mind that this raises your led, and the legs of the LDR should stick out far enough to compensate for that.

Controls

• Attack

• Release

• Tone

• Sustain

• Ratio

• Level

For further analysis on this circuit take a look at this thread on Free Stomp Boxes Forum.

For any technical questions regarding this build don’t forget to check out our Facebook Group and our forum at Free Stomp Boxes.

Tone Guard Device – Building Docs

Tone Guard Device – Drilling Template

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 52 rows

Report a wrong parse

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

RefValueNormalizedTypeNotes
Resistors 18
R16100K100k
R210K10k
R710K10k
R810K10k
R1210K10k
R310M10M
R151K1k
R11M1M
R61M1M
R91M1M
R101M1M
R522K22k
R42M22.2M
R1347K47k
R1747K47k
R1847K47k
R114K74.7k
RLED4K74.7k
Capacitors 17
C4100n100n
C16100n100n
C1100p100p
C3100p100p
C21u1u
C111u1u
C622n22n
C722n22n
C1022n22n
C13100u100u
C1410u10u
C1510u10u
C1710u10u
C51u1u
C91u1u
C121u1u
C847u47u
Diodes 5
D61N40011N4001
D71N40011N4001
D11N41481N4148
D21N41481N4148
D01N58171N5817
Transistors 3
Q22N50892N5089
Q32N50892N5089
Q1MPSA18MPSA18
ICs 1
IC2TC1044TC1044
Opto 1
LDR1PhotoPHOTO
Potentiometers 6
RATIOB100KB100k
TONEB100KB100k
ATTACKB10KB10k
LEVELB50KB50k
RELEASEB50KB50k
SUSTAINC1MC1M
LEDs 1
D3LEDLED

Other boards based on the EarthQuaker Devices The Warden