aion STRATUS User manual

STRATUS CLASSIC OVERDRIVE 1
PROJECT NAME
STRATUS
BASED ON
EFFECT TYPE
PROJECT SUMMARY
DOCUMENT VERSION
Ibanez TS-9 Tube Screamer
The quintessential mid-hump overdrive pedal made famous by Stevie Ray Vaughan, and the source cir-
cuit behind dozens of high-dollar boutique pedals.
Overdrive 1.0.0 (2018-09-22)
BUILD DIFFICULTY
Easy
Actual size is 2.3” x 1.86” (main board) and 2.3” x 0.86” (bypass board).

STRATUS CLASSIC OVERDRIVE 2
TABLE OF CONTENTS
1Project Overview 7Drill Template
2Introduction & Usage 8Enclosure Layout
3-4 Parts List 9Wiring Diagram
5Build Notes 10 Licensing
6Schematic 10 Document Revisions
INTRODUCTION
The Stratus Classic Overdrive is a recreation of the Ibanez TS-9 Tube Screamer, first released in 1979 as
the OD-808 Overdrive by Maxon and then later licensed to Ibanez.
Originally designed to compete with the Boss OD-1 Overdrive, the TS-808 and TS-9 added the now-
famous tone control, but are otherwise very similar to the OD-1 with regards to the feedback diode-
clipping arrangement.
The Tube Screamer is one of the most popular DIY effects, and it serves as the source circuit for a
number of boutique effects including the Landgraff Dynamic Overdrive, the Fulltone®Fulldrive, and the
Lovepedal Eternity.
The new 125B version of the Stratus has been completely overhauled, reducing some flexibility in favor
of an easier and more straightforward build. The previous version of the Stratus will remain available.
USAGE
The Stratus has the same control layout as most overdrive or distortion effects:
• Tone controls the treble response of the effect. The center point (12:00) is flat. When turned to the
left, it cuts treble, and when turned to the right, it boosts treble.
• Drive controls the amount of gain in the op-amp feedback diode clipping stage.
• Volume controls the overall output of the effect.
In addition, there are two switch modifications included for added flexibility:
• Clipping selects the clipping diodes which changes the character of the drive tone.
• Bass sets the low-end EQ of the clipping stage. The stock Tube Screamer value is in the middle
position, while the two other switch positions add more bass to the signal.

STRATUS CLASSIC 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 →
Note: Values shown are for the original TS-808.
PART VALUE TYPE NOTES
R1 1k Metal film resistor, 1/4W
R2 510k Metal film resistor, 1/4W
R3 10k Metal film resistor, 1/4W
R4 10k Metal film resistor, 1/4W
R5 4k7 Metal film resistor, 1/4W
R6 51k Metal film resistor, 1/4W
R7 1k Metal film resistor, 1/4W
R8 10k Metal film resistor, 1/4W
R9 220R Metal film resistor, 1/4W
R10 1k Metal film resistor, 1/4W
R11 1k Metal film resistor, 1/4W
R12 510k Metal film resistor, 1/4W
R13 10k Metal film resistor, 1/4W
R14 100R Metal film resistor, 1/4W TS-808 value. Change to 470R for TS-9 specs.
R15 10k Metal film resistor, 1/4W TS-808 value. Change to 100k for TS-9 specs.
R16 10k Metal film resistor, 1/4W
R17 10k Metal film resistor, 1/4W
RPD 2M2 Metal film resistor, 1/4W Input pulldown resistor. Can be as low as 1M.
LEDR 4k7 Metal film resistor, 1/4W LED current-limiting resistor. Adjust value to change LED brightness.
C1 22n Film capacitor, 7.2 x 2.5mm
C2 1uF Film capacitor, 7.2 x 3.5mm
C3 47pF MLCC capacitor, NP0/C0G Original value is 51pF, but 47pF is the nearest standard value. No
difference in tone.
C4 47n Film capacitor, 7.2 x 2.5mm
C5 220n Film capacitor, 7.2 x 2.5mm
C6 220n Film capacitor, 7.2 x 2.5mm
C7 1uF Film capacitor, 7.2 x 3.5mm
C8 100n Film capacitor, 7.2 x 2.5mm

STRATUS CLASSIC OVERDRIVE 4
PARTS LIST, CONT.
PART VALUE TYPE NOTES
C9 1uF Film capacitor, 7.2 x 3.5mm
C10 100uF Electrolytic capacitor, 6.3mm Power supply filter capacitor.
C11 47uF Electrolytic capacitor, 5mm Reference voltage filter capacitor.
C12 100n MLCC capacitor, X7R Power supply filter capacitor.
CX2 22n Film capacitor, 7.2 x 2.5mm
CX3 68n Film capacitor, 7.2 x 2.5mm
D1 1N5817 Schottky diode, DO-41
D2 1N914 Fast-switching diode, DO-35
D3 1N914 Fast-switching diode, DO-35
D4 1N914 Fast-switching diode, DO-35
D5 1N914 Fast-switching diode, DO-35
D6 1N914 Fast-switching diode, DO-35
D7 1N914 Fast-switching diode, DO-35
D8 5mm LED, 5mm, red diffused
D9 5mm LED, 5mm, red diffused
Q1 2N5088 BJT transistor, NPN, TO-92
Q2 2N5088 BJT transistor, NPN, TO-92
IC1 JRC4558D Operational amplifier, DIP8
IC1-S DIP-8 socket IC socket, DIP-8
TONE 20kW 16mm right-angle PCB mount pot
DRIVE 500kB 16mm right-angle PCB mount pot
VOL 100kA 16mm right-angle PCB mount pot
CLIP SPDT cntr off Toggle switch, SPDT on-off-on
BASS SPDT cntr off Toggle switch, SPDT on-off-on
LED 5mm LED, 5mm, red diffused
IN 1/4" stereo 1/4" phone jack, closed frame Switchcraft 112BX or equivalent.
OUT 1/4" mono 1/4" phone jack, closed frame Switchcraft 111X or equivalent.
DC 2.1mm DC jack, 2.1mm panel mount Mouser 163-4302-E or equivalent.
BATT Battery snap 9V battery snap Optional. Use the soft plastic type—the hard-shell type will not fit.
FSW 3PDT Stomp switch, 3PDT
ENC 125B Enclosure, die-cast aluminum Can also use a Hammond 1590N1.

STRATUS CLASSIC OVERDRIVE 5
BUILD NOTES
Clipping Switch
The clipping switch allows you select between different sets of diodes.
The downward position of the toggle switch is the stock Tube Screamer clipping arrangement, which has
one silicon diode in each direction. The upward position of the toggle is two diodes in each direction, a
higher clipping threshold with a more open sound. The center position leaves only the LEDs for a more
dynamic and transparent tone.
If you look at the schematic, you’ll see that the LEDs, D8 and D9, are always connected. However, in
either the up or down switch positions, the lower-threshold diodes are connected and so the LEDs have
no effect—there’s no signal left for them to clip.
Feel free to experiment, For example, you could jumper D7 for asymmetrical clipping as in the Boss SD-1
Super Overdrive. Or, you could omit the two clipping LEDs for a diode-lift mode in the center position.
Bass Switch
The bass switch selects between different EQ settings. Using the default configuration, the center
position is the stock Tube Screamer bass setting. The downward position adds more bass and the
upward position adds even more.
Like the clipping switch, you can experiment with the values here as well to tweak the sound to your
liking. The stock Tube Screamer capacitor is C4, and the toggle switch puts CX2 or CX3 in parallel with
it (parallel capacitors add their values to each other). By tweaking CX2 and CX3, you can fine-tune the
bass settings to something you’d find useful.
There’s also a way to set it up for “less bass” if you want. Reduce the value of C4 to something like 33n to
make the center position a bass-cut setting. Then make CX2 a 10n or 15n capacitor to put it very close
to the 47n stock value. CX3 could be kept at 68n.

SCHEMATIC
STRATUS CLASSIC OVERDRIVE 6
1k
510k
10k
10k
4k7
51k
1k
10k
220R
1k
1k
510k
10k
100R
10k
10k
2M2
22n
1uF
47pF
47n22n
220n
1uF
100n
1uF
2N5088
JRC4558D JRC4558D
10k
GND
20kW
500kB
100kA
2N5088
GND
GND GND
220n
GND
68n
1N5817
GND GNDGND
+9V VA
GND
VA
VB
VB
VB
VB
VB
VB
VB
GND
100uF 47uF
100n
GND
VA
VA
IN
OUT
R1
R2
R3
R4
R5
R6
R7
R8
R9
R10
R11
R12
R13
R14
R15
R16
RPD
C1
C2
C3
C4CX2
C6
C7
C8
C9
Q1
2
3
1
IC1A
6
5
7
IC1B
84
R17
TONE
1
2
3
DRIVE
1
2
3
LEVEL
1
2
3
Q2
D3
D2
D4D5
D6 D7
C5
CX3
D1
CLIP
2
3
1
C10 C11
C12
BASS
2
3 1
D8 D9
For TS-9, change R14 to 470R and R15 to 100k.
Shown with TS-808 values.

STRATUS CLASSIC OVERDRIVE 7
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.
Top jack layout assumes the use 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 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.
x: -0.65, y: +1.71 x: 0.65, y: +1.71
ø9/32” ø9/32”
x: -0.85, y: +0.66
ø1/4”
x: 0, y: +0.66
ø9/32”
x: 0, y: -1.20
ø15/32”
x: -0.775, y: -1.20
ø5/16”
CENTER (0,0)
ø3/8” ø1/2”
0.385”
0.625” 0.625”
ø3/8”
OUT DC IN
125B
VOLUME
BASS CLIPTONE
DRIVE
FOOTSWITCHLED
x: +0.85, y: +0.66
ø1/4”
0 1 2
CM
0 1
INCH

STRATUS CLASSIC OVERDRIVE 8
ENCLOSURE LAYOUT
Enclosure is shown without jacks. See next page for jack layout and wiring.
125B

STRATUS CLASSIC OVERDRIVE 9
WIRING DIAGRAM
125B
IN +VGND N.C. N.C. OUT
PCB
IN
GND +V +V JACK GND JACK
OUTIN
GND GND PCB
OUT
Shown with optional 9V battery. If battery is omitted, both jacks can be mono rather than one being stereo.
Leave the far-right lug of the DC jack unconnected.

STRATUS CLASSIC OVERDRIVE 10
LICENSE & USAGE
No direct support is offered for these projects beyond the provided documentation. It’s assumed
that you have at least some experience building pedals before starting one of these. Replacements and
refunds cannotbe offered unless it can be shown that the circuit or documentation are in error.
All of these circuits have been tested in good faith in their base configurations. However, not all the
modifications or variations have necessarily been tested. These are offered only 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 always greatly appreciated. The only usage restrictions
are that (1) you cannot resell the PCB as part of a kit without prior arrangement, and (2) you cannot
“goop” the circuit, scratch off the screenprint, or otherwise obfuscate the circuit to disguise its source.
(In other words: you don’t have to go out of your way to advertise the fact that you use these PCBs, but
please don’t go out of your way to hide it. The guitar effects industry needs more transparency, not less!)
DOCUMENT REVISIONS
1.0.0 (2018-09-22)
Initial release.