Modding a DS-2

[Blues_Boy_4096]

OK, I'm trying to change a DS-2 for bass, there are a lot of caps over there   

Here's the schematic: http://www.mif.pg.gda.pl/homepages/tom/files/DS-2.gif

Well the caps I'm thinking of changing are C12, C40, C39, C43, C44, C45, C32, C33, C34, C26, C21, C28 and C29.
I'm also thinking of doubling the values of those caps, as a starting point...

Well, my question is: do you guys think it's really needed to change all those caps, some more or only the input and output ones?

Thanks for your help!

[Blues_Boy_4096]

Sorry for being a PITA, but... any thoughts on this?

[Gila_Crisis]

this are some mods you can do:

The function of D14-15 is pretty unclear to me, they don't add clipping nor affect the volume or tone, so I just keep them in. D11-12 have the biggest effect on the distortion, you really hear the difference when you use a LED or silicon/germanium diode here.  D8-9 have the least effect, I mean, you do hear the difference, but it doesn't really change the overall tone, the effect blends in with D11-12.
I use a Germanium in D8, D9 is standard, D11 standard and D12 a 5mm red Led. This gives me an awesome cruchy distortion, and with the neck pickup and dist to full even fuzzy disortion, it's really cool.
But the best thing is when you totally turn down the dist and volume way up, it makes my amp sound like it's on volume 10 except it's on 2.

I took some time to take appart the tonesection, and found out that it does a lot more than only cutting or boosting trebble.
R45: (4.7K) The lower you go, the more bass it cuts in total. You can't go further than bypassing it.
R46: (33K) The higher you go, the more thump you get when the gain is at 2'o clock. So if you like medium gain, make this 100K or something in that area.
R58: (15K) The higher you go, the more upper bass you get, but you lose a fair bit of volume this way. Leaving it standard prooved to sound the best.
R59: (1K) This is the bitch. The higher you go, the less blistering the trebble gets. I needed to take this part out to satisfy my needs.
You can also put a cap parallel to R46 to be able to cut more, something like 3.3nF has a pretty good result.

R32 is responsible for the midscoop in this pedal. I'm gonna try something lower than 1M to make it sound less scooped. It will probably result in a little more ouput too.
R62 can suposedly be lowered to have more volume, I need to check this.
R57 can suposedly be altered to change the compressed feeling, but it will also affect the bass, I need to check this too.

This may have been mentioned, but doubling C33 will increase the gain and bass

C41 could be changed to a higher value to allow more bass frequencies to pass freely, altough it could result in muddy or musshy sound

C34 is now 10nF, the sound is more focused, less high frequency harshness but middle stays sharp and gritty...

A second general area for modding in a manner that creates big changes with minimal investment is likely the EQ section.  The DS-2 uses what seems to be a fairly common treble boost-cut circuit, whose turnover frequency is set by what looks like C37 (the 6800pf cap tied to the wiper of the tone control).  Swap that cap for something of a larger value (8200pf/.0082 to maybe .012 or.015uf) and the turnover frequency will drop proportionately.  Make it smaller (.0056 to maybe .0033) and the turnover frequency will move upwards.  Having a higher turnover frequency will mean that when you turn the tone down, it will round off the edges but leave more mid-bite, and turning it up will simply change the higher extremes but not affect the mids.  Having a lower turnover frequency will mean that when you boost you will increase the mids a lot more in addition to the highe end, and when you turn down the sound will get much darker than it does now.

When Q10 is turned on, then it is like R32 is not there and the junction of R44/R33 goes to ground directly through the cap.  C29 determines how much of the highs and mids come through.  If you want more upper mids, then make it .01, if less, make it .0033.  C21 determines where the low end of the scoop rolls off.  It is around 720hz as shown.  You can drop that if you increase C21 to .012 or .015, and raise it if you drop C21 to .0082 or .0068.  Letting more upper mids and upper bass through will decrease the scoopiness."
You really only need to lift C21 to removed the notch.
Q10 actually switches the notch in and out ie. one of the modes doesn't have the notch in circuit.
Because the input impedance of Q12 is high R33, R44 and C28 are benign once C21 is removed.
Adjusting C29 is beyond the scope of the notch, that component modifies the voicing of highs - you can play around with that if you wish.  Keep in mind the tone control is slightly asymmetrical anyway.