This is a library of perfboard and single-sided PCB effect layouts for guitar and bass. I'm not an electrical engineer by any stretch of the imagination, just a DIY'er who likes drawing layouts. It is meant for the hobbyist (so commercial use of any of these layout is not allowed without permission) and as a way to give back to the online DIY community.

Tuesday, April 10, 2018

Boss DS-1 with Keeley Ultra Mods

Got a request for the classic DS-1 with some Keeley mods and since my earlier DS-1 layout doesn't have board mounted pots, it seemed like a good idea. The flip-flop switching has been removed. Here's the schematic for reference.


  1. Brutal!
    The switch should be SPDT, no?

  2. Is the switch in the layout to switch between the modded DS-1 and stock DS-1 . Switch is SPDT on-on?

    Thank you.

  3. I bet it is supposed to be only sw 2 and 3 to choose between symmetrical or asymmetrical clipping. so it is correct using SPST. so the sw 1 shouldn't be there.

  4. For Dual Opamp I'm thinking to use the LM358
    Its that ok?


  5. Congrats for all your hard work! This is just awesome. Last week I was thinking of building the DS1, but the stock model is too cheap and not interesting enough to replicate... Can't wait to build this one w/mods!
    I have a request (if doable and you find time to do it, of course)... Would it be possible to do the chorus/rev section of a Rockman X100 in a stompbox format? I've unsuccessfully tried to find this in several forums and websites. While the dist/OD section of the Rockman has already been cloned (e.g. ROG's Mockman), that chorus-reverb stage is pretty unique, very coveted and, as far as I know, not replicated yet.
    If interested, I've been gathering patent docs, pictures and schematics for some weeks, but I'm afraid I lack the skills to properly read into all this info...
    Thanks again for your website and amazing efforts.

    Cheers from Spain


  6. hi everybody
    i,ve been trying to build this one, but i cant get it running!
    when i plug the dc power in, i get a very distorted signal, but after a few seconds the signal is nearly = 0!
    seems like iḿ loosing power somewhere after a short while.
    ( it could also be, that i have an error in my self etched pcb! )
    if anybody buildt it successfully, please let me know!
    thanks again for your great work

  7. From layout, Q3 has no bias voltage, you should connect R 1M between Q3 pin B and Vb 4.5v (The orange line).

  8. Since, this is unverified and people seem to be having problems, I thought that I would check the layout against the schematic published by Phillip Bryant before populating the board.

    Now I may be being stupid, but having decided to start with the dual op-amp pinout, I cannot match most of the pins on the layout to the schematic.

    I am assuming that the 8 pins for the kind dual op-amp used here (TL072 etc…), when seen from above with the notch at the top, run:

    - left side top to bottom = 1 through 4
    - right side bottom to top = 5 through 8.

    In which case, I can agree pin 4 going to the negative earth and pin 8 to positive 9V, but cannot match the other 6 pins between the layout and schematic.

    Per the schematic pins 1, 2 and 5 should be connected together, but the layout has pins 7, 6 and 3 connected. The schematic shows pin 3 connecting to the 1N4148 diode and 20K resistor, whereas on the layout it is pin 5 that is so connected. Per the schematic pin 6 should connect to a 100K resistor, but on the layout it is pin 2 that does this. Finally, per the schematic pin 7 should connect to the 1K5 resistor, but the layout has pin 1 so connected.

    It appears that when compared to the schematic, on the layout:
    - pin 1 has become pin 7 and visa versa
    - pin 2 has become pin 6 and visa versa
    - pin 3 has become pin 5 and visa versa
    - pin 4 is in agreement
    - pin 8 is in agreement.

    I cannot explain the above in terms of simply reorienting the chip north-south, flipping the chip over = mirror image, etc… Is it me? Am I doing something stupid?

    I do not have the software to easily change the layout and I have already etched one board, so I may just cross wire the socket to the board to make the above pin changes and see how that goes, but I need to also check the rest of the schematic first.

    1. Dual op amps are 2 op amps in one package. Like you said, pin 4 is ground and pin 8 is power. Pins 1-3 are one op amp (pin 3 the positive input, 2 the negative input, and 1 the output), and pins 5-7 are the other op amp (pin 5 the positive input, 6 the negative input, and 7 the output). These 2 op amps are identical. So using swapping sides of the chip isn't going to make the circuit not work. I did that to make it easier to lay out.

  9. Thanks, for the information (and the great site). I am glad it is not a problem, just me being dumb.

    I only recently started making guitar effects again. The first time being when I was a kid, nearly 50 years ago. There were no ICs then, the most complex 'solid state' device being a transistor. So plenty of stuff to learn and re-learn. I just assumed that in real world applications there must be some difference between op-amp A and B, although logically there is no reason for this.

    I will try and get one of these completed this week.

  10. Built and working.

    I do not have a Keeley Ultra modded original DS-1, so I cannot guarantee that it is a faithful reproduction, but I do have an unmodified Boss DS-1, which was purchased in used condition about 30 years ago. Compared to my old DS-1, this has:

    - much more bass (the result, I guess of the larger capacitors)
    - a significantly greater output level (12 o'clock is already well above unity)
    - more gain/distortion on tap.

    It sounds less fizzy/tinny than the unmodified unit and switching in the second red LED gives serious clipping.

    As it was unverified, I built it used the cheapest components in my parts bin, mostly Chinese in origin, including FR2 board, some 1u ceramic capacitors, 2N5088s with an hFe of only about 280-300 rather than the more typical 500-550 and an IC that is probably not even a genuine TL072, although it is so marked. Yet, it still does not sound bad. I think it would be worth a build with good quality components and then trying out with some better quality transistors and a range of genuine ICs.

  11. Hi just build it but I have a big volume drop and a bit of an oscillation...
    any thought?

  12. Thanks for the work. Built and working without problems.
    Instead of 2n5088 I used 2n3904s. 2.4K resistor is 2K / 20K resistor is 22 on my build.
    The sound has some hiss/white noise probably because of grounding ..etc. I had compared it with my stock ds-1 and stock one has the same noise when every knob is at max. Also I used 4580 ic.

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  15. So I completed this build and having never owned a DS1 I am not sure if this is a problem but I cannot get it to clean up with the distortion knob. It is heavily clipped even all the way down. I can see the LEDs clip harder as it's increased so it's doing something but I am at a loss what to troubleshoot if this is not normal.
    Also my distortion is extremely muddy through this circuit. Any advice on seeing if these are actually problems and how to resolve them would be greatly appreciated!

  16. Hi, can use multi layer ceramic caps MLCC for 1uF and 0.1uF 's ?

  17. If I use 2n5089 instead of 2n5088 do I have to make any adjustment to the values ​​of the other components?

  18. Hi everybody! I have very importrant info about ds 1. I tried to do ds-1 with single tl 061,071 & i got very fuzz distortion with octave harmonics, i checked up everything!!! Nothing, i tried differetnts trsnsistors-same! I made this Keeley & i have the same troubles. I tried tl 062,072,082,NE 5535 - nothing! Today i found next info about using differents opamps,just look at this:
    All you need - to change couple resistors about Q2!

  19. Is the installation of 1uf allowed back and forth?

    1. As long as you're using a non-polarized 1uF cap it doesn't matter how it's oriented.

    2. what if i keep using the polarized electrolytic condensator?

    3. For the 4, 1uF caps, if you're going to use polarized caps, here's how they should be oriented (going from left to right):

      -negative to ground
      -negative to Sw1
      -negative on the left toward the 100k resistor
      -negative to Out

      Hope that helps.

    4. I have made it 3 times, and it always fails, even though I have memorized the path exactly like the picture. whether all the resistors used must be 0.25 watts, so far I have used 0.5 watts

  20. Its verified !awesome ds1!!
    Regards fr Philippines!Jun.