aion theseus User manual

THESEUS DUAL OVERDRIVE 1
PROJECT NAME
THESEUS
BASED ON
EFFECT TYPE
PROJECT SUMMARY
DOCUMENT VERSION
Analogman King of Tone
One of the earliest boutique “waitlist” pedals, this dual-channel drive is made up of two modified Mar-
shall Bluesbreaker circuits in series.
Dual-channel overdrive 1.0.1 (2022-05-13)
BUILD DIFFICULTY
Intermediate
Actual size is 4.4” x 1.52” (main board) and 4.00” x 0.74” (bypass board).

THESEUS DUAL OVERDRIVE 2
TABLE OF CONTENTS
1Project Overview 8Drill Template
2Introduction & Usage 9Enclosure Layout
3-5 Parts List 10 Wiring Diagram
6Build Notes 11 Wiring Diagram (no send/return loop)
7Schematic 12 Licensing & Document Revisions
INTRODUCTION
The Theseus Dual Overdrive is based on the Analogman King of Tone, a dual-channel drive pedal first
released in 2003 that played a big part in kicking off the boutique/handmade pedal trend. In the past
two decades it has only grown in popularity, and last we checked the waitlist is around 4 ½ years.
The King of Tone is essentially two modified Marshall Bluesbreakers in series, each independently
switchable so they can be used on their own or stacked one into the other for a more complex and
natural overdriven sound. Each channel has an internal presence control as well as DIP switches that
control the clipping diode configuration.
In 2009, Analogman began offering a “high gain” modification that can be selected as part of the
customization. We’ve added a third DIP switch position to allow this to be switchable per channel
instead of being a hard-wired modification.
Otherwise, the Theseus is a direct clone of the King of Tone, but with one added convenience: a send/
return loop between the channels. This allows the two pedals to be split up so you can have more
flexibility in where they are used on the pedalboard, or put something in between them such as a boost
or EQ for added tone shaping. If nothing is plugged into the send/return jacks, the loop is disabled.
In 2012, Analogman released the Prince of Tone, a single-channel version with a few extra tweaks. The
Prince of Tone is available from Aion FX as the Achilles Amp Overdrive.
USAGE
The Theseus has three external controls per channel:
• Drive controls the amount of gain going into the op-amp feedback diode clipping stage.
• Tone controls the treble response of the channel via a passive filter.
• Volume controls the overall output of the channel.
In addition, each channel has four internal controls:
• Presence (trimmer) is an additional passive treble control. The default position is all the way down
(full CCW) and as you turn it up it adds high-end. Noise or hiss will increase as well.
• Soft Clip (DIP switch) enables or disables the soft clipping. Default position is up (enabled).
• Hard Clip (DIP switch) enables or disables the hard clipping. Default position is down (disabled).
• High Gain (DIP switch) enables or disables the high-gain mode. Default position is up (low gain).

THESEUS DUAL OVERDRIVE 3
PARTS LIST
This parts list is also available in a spreadsheet format which can be imported directly into Mouser for
easy parts ordering. Mouser doesn’t carry all the parts—notably potentiometers—so the second tab lists
all the non-Mouser parts as well as sources for each.
View parts list spreadsheet →
PART VALUE TYPE NOTES
R1 1M Metal film resistor, 1/4W
R2 100k Metal film resistor, 1/4W
R3 1k Metal film resistor, 1/4W
R4 27k Metal film resistor, 1/4W
R5 33k Metal film resistor, 1/4W
R6 10k Metal film resistor, 1/4W
R7 220k Metal film resistor, 1/4W
R8 6k8 Metal film resistor, 1/4W
R9 1k Metal film resistor, 1/4W
R10 6k8 Metal film resistor, 1/4W
R11 1M Metal film resistor, 1/4W
R12 47k Metal film resistor, 1/4W
R13 47k Metal film resistor, 1/4W
R14 1M Metal film resistor, 1/4W
R15 100k Metal film resistor, 1/4W
R16 1k Metal film resistor, 1/4W
R17 27k Metal film resistor, 1/4W
R18 33k Metal film resistor, 1/4W
R19 10k Metal film resistor, 1/4W
R20 220k Metal film resistor, 1/4W
R21 6k8 Metal film resistor, 1/4W
R22 1k Metal film resistor, 1/4W
R23 6k8 Metal film resistor, 1/4W
R24 1M Metal film resistor, 1/4W
R25 47k Metal film resistor, 1/4W
R26 47k Metal film resistor, 1/4W
R27 100R Metal film resistor, 1/4W
R28 100R Metal film resistor, 1/4W
R29 4k7 Metal film resistor, 1/4W LED current-limiting resistor (Ch. A) which affects LED brightness.
R30 4k7 Metal film resistor, 1/4W LED current-limiting resistor (Ch. B) which affects LED brightness.
RPD1 1M Metal film resistor, 1/4W Channel A input pulldown resistor. Can be anywhere from 1M to 2.2M.
RPD2 1M Metal film resistor, 1/4W Channel B input pulldown resistor. Can be anywhere from 1M to 2.2M.

THESEUS DUAL OVERDRIVE 4
PARTS LIST, CONT.
PART VALUE TYPE NOTES
C1 22n Film capacitor, 7.2 x 2.5mm
C2 100pF MLCC capacitor, NP0/C0G
C3 10n Film capacitor, 7.2 x 2.5mm
C4 10n Film capacitor, 7.2 x 2.5mm
C5 100n Film capacitor, 7.2 x 2.5mm
C6 10n Film capacitor, 7.2 x 2.5mm
C7 10n Film capacitor, 7.2 x 2.5mm
C8 1uF Film capacitor, 7.2 x 3.5mm
C9 1uF Electrolytic capacitor, 4mm
C10 100uF Electrolytic capacitor, 6.3mm Reference voltage filter capacitor.
C11 22n Film capacitor, 7.2 x 2.5mm
C12 100pF MLCC capacitor, NP0/C0G
C13 10n Film capacitor, 7.2 x 2.5mm
C14 10n Film capacitor, 7.2 x 2.5mm
C15 100n Film capacitor, 7.2 x 2.5mm
C16 10n Film capacitor, 7.2 x 2.5mm
C17 10n Film capacitor, 7.2 x 2.5mm
C18 1uF Film capacitor, 7.2 x 3.5mm
C19 1uF Electrolytic capacitor, 4mm
C20 100uF Electrolytic capacitor, 6.3mm Reference voltage filter capacitor.
C21 100uF Electrolytic capacitor, 6.3mm Power supply filter capacitor.
C22 100uF Electrolytic capacitor, 6.3mm Power supply filter capacitor.
C23 100n MLCC capacitor, X7R Power supply filter capacitor.
D1 1N5817 Schottky diode, DO-41
D2 BAS33 Switching diode, DO-35
Original uses MA856 diodes. The BAS33 is the closest available diode
currently in production. See build notes.
D3 BAS33 Switching diode, DO-35
D4 BAS33 Switching diode, DO-35
D5 BAS33 Switching diode, DO-35
D6 1N914 Fast-switching diode, DO-35
D7 1N914 Fast-switching diode, DO-35
D8 BAS33 Switching diode, DO-35
Original uses MA856 diodes. The BAS33 is the closest available diode
currently in production. See build notes.
D9 BAS33 Switching diode, DO-35
D10 BAS33 Switching diode, DO-35
D11 BAS33 Switching diode, DO-35
D12 1N914 Fast-switching diode, DO-35
D13 1N914 Fast-switching diode, DO-35

THESEUS DUAL OVERDRIVE 5
PARTS LIST, CONT.
PART VALUE TYPE NOTES
IC1 JRC4580D Operational amplifier, single, DIP8
IC1-S DIP-8 socket IC socket, DIP-8
IC2 JRC4580D Operational amplifier, single, DIP8
IC2-S DIP-8 socket IC socket, DIP-8
MODE 6-pos DIP DIP switch, 6-position
PRES. A 50k trimmer Trimmer, 10%, 1/4"
PRES. B 50k trimmer Trimmer, 10%, 1/4"
DRIVE A 100kB 16mm right-angle PCB mount pot
DRIVE B 100kB 16mm right-angle PCB mount pot
TONE A 25kB 16mm right-angle PCB mount pot
TONE B 25kB 16mm right-angle PCB mount pot
VOL. A 100kA 16mm right-angle PCB mount pot
VOL. B 100kA 16mm right-angle PCB mount pot
LED A 5mm LED, 5mm, red diffused
LED B 5mm LED, 5mm, red diffused
IN 1/4" mono 1/4" phone jack, closed frame Switchcraft 111X or equivalent.
OUT 1/4" mono 1/4" phone jack, closed frame Switchcraft 111X or equivalent.
SEND NMJ6HC-S 1/4" phone jack, stereo, switched
RETURN NMJ6HC-S 1/4" phone jack, stereo, switched
DC 2.1mm DC jack, 2.1mm panel mount Mouser 163-4302-E or equivalent.
CH. A 3PDT Stomp switch, 3PDT
CH. B 3PDT Stomp switch, 3PDT
ENC 1590BBS Enclosure, die-cast aluminum

THESEUS DUAL OVERDRIVE 6
BUILD NOTES
Clipping diodes
The King of Tone uses MA856 diodes, which clip at a slightly higher threshold than standard silicon
diodes such as 1N914 (approximately 0.82V compared to 0.7V). These diodes are long out of production
and have almost entirely disappeared from the old-stock market, likely all bought up by Analogman and
other cloners.
The BA282 and BA283 are very close to the MA856, and were the popular substitute among builders
for awhile... until they dried up too.
Now, the closest option is the BAS33. These clip at around 0.8V, still significantly higher than the 1N914
and only slightly lower than the MA856. We’ve compared the curves on a Peak DCA75 and confirmed
that they closely match the MA856 across the current test range.
The only problem is that the BAS33 went end-of-life in early 2022. Availability is still high, but
eventually they’ll join the ranks of the others.
Omitting the send/return jacks
The loop between the two channels is a modification that is not in the original King of Tone. This loop
automatically shorts together if nothing is plugged in, so it’s fully backwards-compatible if you don’t use
this feature. However, if you do want to omit it entirely, see the alternate wiring diagram on page 11.
Enclosure size
This project was designed for the Hammond 1590BBS enclosure, which has the same height as the
125B or 1590N1. If you don’t use the Hammond brand, be careful—not all 1590BBS enclosures are the
same. For example, Love My Switches sells two different types, and the CNC Pro version is correct while
the standard one is too short.
The 1590BB2 seems like a close equivalent, but it’s about 4mm shorter. It may be possible to fit this
circuit in a 1590BB2, but we have not tested it, so you’re on your own!
Another alternative is the 1590C (also available from Tayda and Love My Switches). It’s about 10mm
taller than necessary, but if that’s all you can find then it will definitely work.

SCHEMATIC
THESEUS DUAL OVERDRIVE 7
CH.B OUT
CH.A IN
CH.B IN
CH.A OUT
CHANNEL A
FROM
INPUT
CHANNEL A
FROM
TO
OUTPUT
TO
CHANNEL B
TO
CHANNEL B
FROM
IN
JACK
OUT
IN
JACK
OUT
VA VC VA VC
TO
SEND
RETURN
FROM
4k7
5MM
1N5817
+9V
100n
BYP_GND
BYP_GND
100kA
25kB
100kB
1M
GND
100R
47k
47k
GND
100uF
GND
100uF
VB
47k
47k
100uF
VC VDVA
BYP_GND
100R
100uF
BYP_GND GND2 GND2
4k7
5MM
BYP_GND
1M
GND2
22n
TL072P
TL072P
VA
GND
100pF
100k
1M
VB
27k
33k
10n
10n
GND
10k
100n
VB
220k
6k8
VB
1k
10n
VB
6k8
50kB
10n
VB
1k
VB
1uF 1uF
1M
GND
100kA
25kB
100kB
22n
TL072P
TL072P
100pF
100k
1M
27k
33k
10n
10n
10k
100n 220k
6k8
1k
10n
6k8
50kB
10n
1k
1uF 1uF
1M
GND2
GND2
GND2
VC
VD
VD
VD
VD
VD
VD
R29
LED A
D1
A2
A3
A1
CHANNEL A
B2
B3 B1
C2
C3
C1
2
1
1
32
1
4
4
1
6
C23
VOLUME_A
1
2
3
TONE_A
1
2
3
DRIVE_A
1
2
3
RPD1
CHANNEL B
C2
C3
C1
B2
B3 B1
A2
A3
A1
R27
R12
R13
C21 C10
R25
R26
C20
1
4
3
4
R28
C22
R30
LED B
RPD2
C1
2
3
1
IC1A
6
5
7
IC1B
84
C2
R2
R1
R4
R5
C3 C4
R6
C5 R7
R8
D2 D3
D4D5
D6 D7
R9
C6
R10
PRESENCE_A
1
2
3
C7
R3
SW_1A
1 2
SW_1B
3 4
SW_1C
5 6
SW_1D
7 8
SW_1E
9 10
SW_1F
11 12
C8 C9
R11
VOLUME_B
1
2
3
TONE_B
1
2
3
DRIVE_B
1
2
3
C11
6
5
7
IC2B
2
3
1
IC2A
84
C12
R15
R14
R17
R18
C13
C14
R19
C15 R20
R21
D8 D9
D10D11
D12
D13
R22
C16
R23
PRESENCE_B
1
2
3
C17
R16
C18 C19
R24
4
3

THESEUS DUAL OVERDRIVE 8
x: -1.725, y: +1.14
ø9/32”
x: -0.575, y: +1.14
ø9/32”
x: +0.575, y: +1.14
ø9/32”
x: +1.725, y: +1.14
ø9/32”
x: -1.725, y: -0.01
ø9/32”
x: +1.725, y: -0.01
ø9/32”
x: +1.60, y: -1.36
ø15/32”
x: -1.60, y: -1.36
ø15/32”
x: -0.825, y: -1.36
ø5/16”
x: +0.825, y: -1.36
ø5/16”
CENTER (0,0)
ø7/16”
1/2”
(12.7mm)
1/2”
(12.7mm)
0.80”
(20.3mm)
1/2”
(12.7mm)
1.60”
(40.6mm)
1.60”
(40.6mm)
ø3/8” ø3/8”
ø7/16”
0.80”
(20.3mm)
ø1/2”
RETURNOUTPUT INPUT
LOOP
SEND
LOOP
DC
VOLUME (B) DRIVE (B) DRIVE (A) VOLUME (A)
TONE (A)TONE (B)
CHANNEL B CHANNEL A
DRILL TEMPLATE
Cut out this drill template, fold the edges and tape it to the enclosure. Before drilling, it’s recommended
to first use a center punch for each of the holes to help guide the drill bit.
Ensure that this template is printed at 100% or “Actual Size”. You can double-check this by measuring
the scale on the printed page.
LED hole drill size assumes the use of a 5mm LED bezel, available from several parts suppliers. Adjust
size accordingly if using something different, such as a 3mm bezel, a plastic bezel, or just a plain LED.
0 1 2
CM
0 1
INCH

THESEUS DUAL OVERDRIVE 9
ENCLOSURE LAYOUT
Enclosure is shown without jacks. See next page for jack layout and wiring.
1590BBS

THESEUS DUAL OVERDRIVE 10
LOOP
SENDINPUT
LOOP
RETURN OUTPUT
DC
VAGNDOUT IN
VAGND
IN
CH.A
OUT
CH.A JACK SND RET +VGND JACK
OUTIN
GND
GND CH.B
OUT
CH.B
IN
VC
IN VC OUT
1590BBS
WIRING DIAGRAM
This is the default wiring diagram with the send/return loop. If you want to omit this loop, see the
modified wiring diagram on the next page.