Exar DS-02 Distortion  [schematic]

All about modern commercial stompbox circuits from Electro Harmonix over MXR, Boss and Ibanez into the nineties.
Post Reply
User avatar
VitaliiBobrov
Breadboard Brother
Information
Posts: 50
Joined: 05 Aug 2020, 15:18
Has thanked: 76 times
Been thanked: 193 times
Contact:

Post by VitaliiBobrov »

I continue to trace Exar pedals from my collection. Today I've traced Distortion from series 2.
Exar DS-02 top
Exar DS-02 top
Exar DS-02 bottom
Exar DS-02 bottom
Series 2 PCBs are easy to trace due to "transparency", my unit seems to be made in 1998 or later due to the dates on the Gain pot (98-01).
Exar DS-02 PCB bottom
Exar DS-02 PCB bottom
Exar DS-02 PCB top on light
Exar DS-02 PCB top on light
Exar DS-02 PCB top
Exar DS-02 PCB top
No surprise as it appeared to be simplified Boss DS-1 or you could consider it as extended Distortion+. It uses ULY7741 by CEMI which is Polish version of LM741.
ULY7741 ak LM741
ULY7741 ak LM741
Attached is the schematic with buffered bypass switching omitted.
Attachments
exar-ds-02-schematic.pdf
Exar DS-02 schematic
(61.58 KiB) Downloaded 279 times

User avatar
CheapPedalCollector
Resistor Ronker
Information
Posts: 399
Joined: 19 Oct 2020, 15:15
Has thanked: 452 times
Been thanked: 147 times

Post by CheapPedalCollector »

Seriously, thank you for tracing all these Exar pedals.

User avatar
VitaliiBobrov
Breadboard Brother
Information
Posts: 50
Joined: 05 Aug 2020, 15:18
Has thanked: 76 times
Been thanked: 193 times
Contact:

Post by VitaliiBobrov »

CheapPedalCollector wrote: 23 Nov 2022, 20:49 Seriously, thank you for tracing all these Exar pedals.
Thanks, I'm also curious about their circuits and was surprised the Exar pedals are just 1:1 clones and they put some engineering to all designs. I collecting them (unfortunately far from getting all 😅) and most of them sound quite good.

User avatar
Ichabod_Crane
Resistor Ronker
Information
Posts: 354
Joined: 26 Apr 2016, 15:11
Has thanked: 83 times
Been thanked: 36 times

Post by Ichabod_Crane »

Is, in the schematic, C13 electrolytic cap well oriented? I expected negative side in the output.

User avatar
mirosol
Resistor Ronker
Information
Posts: 292
Joined: 11 Mar 2012, 16:15
my favorite amplifier: Been on Bogner for quite some time now.
Completed builds: Over 1000 and counting.
Location: TKU, FI
Has thanked: 192 times
Been thanked: 449 times

Post by mirosol »

I guess some Exar pedals have their output caps reversed. No biggie, since little voltage on the wrong side won't harm the poor little cap. I still think it should always by positive side to the portion of a circuit that has higher voltage. At least for longevity. In this case, it definitely should be negative to output.

Anyway.

Here's my layout for the DS-02. ne can easily swap the gain values from negative input to ground etc. Maybe even try on some LEDs and that kind of stuff. Nice alternative for a Boss, nevertheless.
Attachments
Exar-DS02-Distortion.png
http://tagboardeffects.blogspot.com/
http://mirosol.kapsi.fi/
"No such thing as innocence" -Iron Chic

Post Reply