Boss DS-1 true bypass: Success!

[moro]

There was another thread about this which turned into a spiral of self-pity and frustration.

I finally figured out how to do it and it's a very simple mod. I'm sure this is trivial and boring to a lot of people, but for newbies like me, it's exciting stuff.

Here's a photo:



Q6: Remove and put jumper across S & D. (The outside pads.)
Q7: ditto
Q8: Remove.

That's pretty much it. At this point, you can test it by plugging it in. If you step on the switch, the LED will toggle on and off but the effect will always be on.

If that works, you can go ahead and wire it up. Remove the stock momentary switch (wires 13 and 17). Then you can take the input (wire 1), the output (wire 11), and the LED cathode (wire 18) and use your bypass wiring of choice.

Grounding:



12, 13, and 14 are all ground. 12 and 13 are connected on the trace side and 12 is soldered to the input sleeve, so you can remove 13 or connect it to the output sleeve. 14 goes to the battery -, but I don't use batteries so I just removed it and jumpered it to 12. (I juggled the wires a bit. If I did it again, I'd leave 12 and 13 alone and solder wire 14 to one of the jack sleeves.)

I don't think you need to do this, but there's a diode in series with the check LED, which I jumpered. And I replaced the limiting resistor (R35) with a 10K, since I'm using a superbright LED:



And it works. Hooray!



It's worth noting that Q6, Q7, and Q8 are 2SK30As, which are apparently critical in building a Slow Gear. Q6 is a 2SK20AGR and Q7, Q8 are 2SK30AY.

[Pushtone]

Congratulations and thanks for the well documented report and pics.

Your going to be the point man for the next two dozen "How Do I true bypass a Boss pedal" questions that will get posted.



You caught some flak in that other thread for just "wanting" to do a true bypass mod.  As in... why would you want to.
I like to control how many buffers are in my signal chain and where they are so I feel it's total legit to want to do this mod.



All buffers are not evil and TB is not the be and end all of good guitar tone.
The supposed quality of the bypass circuit really has less to do with it than IF you want the buffer there in the first place.

IMHO


Kudos to you for sticking to it

[tranceracer]

Great job Moro!
I was needing a simple mod like this so I dont have to keep pushing the pedal on for my tru bypass ABBA switch box!

BTW, what's that little toggle under the tone knob for?

-tR

[hobojoe]

That extra switch looks like the Keeley DS-1 mod to me

http://www.robertkeeley.com/product.php?id=10

Also if you search around the board I think there are some threads that tell you how to do the keeley mod if you wanna do it yourself

[moro]

Congratulations and thanks for the well documented report and pics.

Thanks!

You caught some flak in that other thread for just "wanting" to do a true bypass mod.  As in... why would you want to.
I like to control how many buffers are in my signal chain and where they are so I feel it's total legit to want to do this mod.

Yeah, that's exactly how I feel.

Great job Moro!
I was needing a simple mod like this so I dont have to keep pushing the pedal on for my tru bypass ABBA switch box!

Is that like a Dancing Queen pedal? What does it do?

BTW, what's that little toggle under the tone knob for?

It's the Keeley Seeing Eye / Ultra mod. Toggles an extra LED in series with one of the clipping diodes.

[moro]

That extra switch looks like the Keeley DS-1 mod to me

Yup. D5 is replaced with a red LED. Then you wire a switch to toggle another red LED in series with D4. The LED is supposed to go inside the "O" of "TONE" but this was the first time I drilled an enclosure and my drill bit walked. So I had to mount the SPDT in that position.

The rest of it is the Melanhead mod, which is like the Keeley, but with less bass:

http://www.diystompboxes.com/smfforum/index.php?topic=32443.0

[tranceracer]

I was needing a simple mod like this so I dont have to keep pushing the pedal on for my tru bypass ABBA switch box!
Is that like a Dancing Queen pedal? icon_confused What does it do?

LOL!  My "Dancing Queen" pedal's on this thread. 
http://www.diystompboxes.com/smfforum/index.php?topic=59874.20

It just reverses the order of two loops:  Gtr>A>B>Amp to Gtr>B>A>Amp.  "A" loop has phase shifter, wah and chorus, "B" loop has overdrive and distortions which includes my DS1, RAT and TubeScreamer.  (;

The board looks more complex than it needs to be because it uses 4049 ICs with soft touch micro switches to activate relays rather than the "clank-clank" of the standard 3PDT switches.

[moro]

LOL!  My "Dancing Queen" pedal's on this thread. 
http://www.diystompboxes.com/smfforum/index.php?topic=59874.20

It just reverses the order of two loops:  Gtr>A>B>Amp to Gtr>B>A>Amp.  "A" loop has phase shifter, wah and chorus, "B" loop has overdrive and distortions which includes my DS1, RAT and TubeScreamer.  (;

That's pretty cool. How do you use it? I find that given any two effects types, there's one order that just sounds "right" to me. I don't have a whole lot of experience in this area though.

[ambulancevoice]

That extra switch looks like the Keeley DS-1 mod to me

Yup. D5 is replaced with a red LED. Then you wire a switch to toggle another red LED in series with D4. The LED is supposed to go inside the "O" of "TONE" but this was the first time I drilled an enclosure and my drill bit walked. So I had to mount the SPDT in that position.

The rest of it is the Melanhead mod, which is like the Keeley, but with less bass:

http://www.diystompboxes.com/smfforum/index.php?topic=32443.0

try using a center punch
worked for me

[tranceracer]

I'm a tone addict... in desperate need of therapy.  (;

I tend to experiment with my tone a lot.  I have a little home studio and  like various types of music from hard/acoustic rock to reggae to hard electronica, hard house and trance (of course). 

I've found that a wah chorus or phase shifter before a distortion sounds subtle a little more "mellow".  If the wah or modulation effects are placed after the distortion they tend to sound much more prominent and provide different distortion tonal qualities.  I love to experiment so this little box just makes rearranging the order flexible and less time consuming than physically disco and reconnecting jacks in the never ending quest to find the perfect tone for that perfect tune.   ((;

-tR

[8mileshigh]

Moro,

Nice work, are you going to bypass the SD-1 as well ?  I'd be game to see those photos as well since I love my modded version but never use it with other pedals due to the bypass issues.

Chris

[moro]

Nice work, are you going to bypass the SD-1 as well ?  I'd be game to see those photos as well since I love my modded version but never use it with other pedals due to the bypass issues.

Yup, I wrote about it here:

http://www.diystompboxes.com/smfforum/index.php?topic=60631.msg475140

[Used666]

After doing all the steps mentioned how do i go about wiring up the switch?

Ive got a 3pdt im going to be using

[Used666]

Anyone have any idea, ive done removed all components/did the gounding now im just wondering how i wire up the switch...

[moro]

I use something similar to this:

http://aronnelson.com/gallery/v/DRAGONFLY-LAYOUTS_0/The-Mod-Zone-_/EZ_3PDT_WIRING.gif.html

But I also ground the effect input when it's being bypassed. So, same wiring but I also connect the top left lug (circuit input) to the unused center lug in the bottom row.

[Used666]

Thanks for the help

[moro]

Cool!

Other people have been able to put the 3PDT on the inside--I'm going to try that with my next Boss pedal.

[Used666]

Luckily i drilled and mounted it just right that i didnt have to put in new wires from the input and ouput jacks

[sevenisthenumber]

Can u do a blues driver? I would loooooove to have that info the way you did these!!!! 
Thanks!!!

[moro]

I don't have a Blues Driver but the bypass on most Boss pedals is the same. There's a transistor right after the input buffer and another one right before the output buffer. These route the signal either through the effect or around it. You remove them and put jumpers where they used to be.

The BD-2 schematic is here:

http://www.freeinfosociety.com/electronics/schemview.php?id=116

It's hard to read the values but I think they're Q4 and Q5? Remove them and put jumpers across the source and drain pads.