Boss True Bypass

All frequent questions on switching: true or not true bypass, transistor-based or mechanical.
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soulsonic
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Post by soulsonic »

Check it out:
Image
That's what I'm talking about... true bypass without hacking up the box!
Made me a little board for it:
Image

I wrote an article about it in my blog.
https://solgrind.wordpress.com/2009/04/ ... -for-boss/
"Analog electronics in music is dead. Analog effects pedal design is a dead art." - Fran

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Silent Fly
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Post by Silent Fly »

Very cool stuff Soulsonic! [smilie=a_bravo.gif]

I would add some more pictures of the component side of the board.

It would also be interesting to see the millennium bypass and switch connections in a generic edited Boss schematics. I think it would help a lot in the understanding of how you implemented the idea.

Thanks for sharing. :thumbsup
"Remember - all I am offering is the truth, nothing more". Morpheus

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Greg
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Post by Greg »

That is clever and very Trick !!

You're a real innovator Soulsonic.. :thumbsup
culturejam wrote: We are equal opportunity exposure artists.

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soulsonic
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Post by soulsonic »

Thanks guys!
For the LED switching, I used the "Millenium 1" with a JFET because it has the least number of components. I used a J201 and it works great - though in the original article R.G. said the JFET Millenium does this slight fade-in thing on the LED, but with the two that I've done so far, the LED comes on instantly without any noticeable fade-in. Maybe it has something to do with using a higher-current LED?

I will see about drawing up something to illustrate how these kind of bypasses are done... but it's fairly straightforward and simple. I removed the two transistors for the flip-flop to disable it, and I replaced the switching FET with a jumper. Then, it was just a matter of hooking up the I/O wires to the bypass switch in the usual way.
"Analog electronics in music is dead. Analog effects pedal design is a dead art." - Fran

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Dirk_Hendrik
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Post by Dirk_Hendrik »

Very sweet!
Sorry. Plain out of planes.

http://www.dirk-hendrik.com

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puppiesonacid
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Post by puppiesonacid »

brilliant!

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Spazzmatazz
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Post by Spazzmatazz »

Soulsonic making history!!

an elegant solution... of course (I prefer non drilled boss with no true bypass).

Is a great Boss pedal Update!!!

PCB?? or stripboard?? Thw whole world needs it!

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Silent Fly
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Post by Silent Fly »

I put together a schematic that shows the Soulsonic’s True Bypass implemented starting from a Boss DS-2.

I hope you will find it interesting.
Boss DS2 - truebypass 02b.gif
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cpm
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Post by cpm »

thats nice if the switch is dpdt

other pedals i've seen use an spdt so it not so easy

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soulsonic
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Post by soulsonic »

cpm wrote:thats nice if the switch is dpdt

other pedals i've seen use an spdt so it not so easy
You must replace the stock switch with a miniature DPDT. That's what the small board is used for - it holds the switch and the JFET circuit for the LED switching. I did the first one on plain perfboard; it's very simple. The only trick is getting the height of the switch adjusted so that it will actuate correctly with the foot treadle.
"Analog electronics in music is dead. Analog effects pedal design is a dead art." - Fran

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Post by minatour87 »

thanks for the information, i wanted to mod an old american metal pedal
peace minatour87

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rasta_maleek
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Post by rasta_maleek »

have anyone the schematic corrected? i think that the old attachement is not the soulsonic one.
thanks a lot for share

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Jack Deville
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Post by Jack Deville »

Hi!

There is a quick way to defeat the flip-flop circuit used in BOSS effects by simply pulling one resistor.
The circuit and defeat is detailed here, Page 3:
http://jackdeville.com/manuals/click_le ... _guide.pdf

Omit Click-Less™ True-Bypass installation and substitute your switch of choice!
:horsey:
I'm a "professional."
Buy my products and make me rich.

www.jackdeville.com

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rasta_maleek
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Post by rasta_maleek »

thanks for the info jack.
Always grettings
Ivan

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