Exar DS-02 Distortion [schematic]

All about modern commercial stompbox circuits from Electro Harmonix over MXR, Boss and Ibanez into the nineties.
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VitaliiBobrov
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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
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CheapPedalCollector
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Post by CheapPedalCollector »

Seriously, thank you for tracing all these Exar pedals.

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VitaliiBobrov
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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.

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Ichabod_Crane
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Post by Ichabod_Crane »

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

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mirosol
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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

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