Boss DS-2 clipping diodes

[guitarist]

By any chance would someone be able to tell me which diodes in this schematic http://www.mif.pg.gda.pl/homepages/tom/files/DS-2.gif are working as clipping diodes? Also would removing these be able to convert the pedal to more of a clean boost as I don't really have any use for the pedal the way it is now?(I've had it for years and my musical tastes have changed)

 

[Chill]

Not quite as simple as a DS-1, now is it? D11 and 12 are your most likely candidates, as they are in the "hard clip" configuration used in the DS-1, rat, D+, and many others. D8 and 9 are the next most likely, they look like they're in "soft clip" configuration a la the tubescreamer, SD-1/OD-1, and big muff. D14 and 15 are a possibility but I don't see how you would get a 1.0-1.4V signal large enough to clip across them at that point in the circuit because there are only two buffers between the input and D14-15, with a gain a little under 1. The rest of the diodes are for the switching jfets or in the votage regulator.

 

[guitarist]

Thanks for the info. I went and removed diodes 11,12,14,15 and left the soft clipping ones.. It seems to have made the pedal louder which makes sense, but it still seems to be harsh sounding even at low dist settings, and not smooth like an overdrive. I'm thinking some of the transistors might be distorting also. Also about diodes 14 and 15, they are of a different type (they are smaller and a bluish green color where the rest are all orange), maybe these type distort at lower signals?

EDIT:
Also I remember reading a long time ago about a mod for removing the clipping diodes in some tube amplifier. After they took the diodes out they put a resistor in their place. Is this just to keep the volume level the same as before or is it something that has to be done after you remove the diodes?

 

[Chill]

Try a lead across C34 for a more trad overdrive sound.

You can stick resistors in there in place of the diodes to ground to pad down the volume somewhat by making the semiconductors work into a load smaller than infinite. As you get lower (and I'm not exactly certain how low), it will start to affect the bandwidth too.

You might be able to tame the harshness by putting caps to ground or supply across some of the resistors to ground or supply in the signal chain. f (-3dB) = 1/ 2 pi R C, with R in ohms and C in farads.

If those don't work, ask over at diystompboxes.com, I'd bet someone has modded a DS-2 before or can tell you how to get closer to what you're after. HTH!