Keeley DS-1 mod - question about C3 and C4 capacitors

[GonzoFonts]

I want to reduce the bass heavy response of my Keeley modded DS-1.

I know I can lower C2 to reduce the bass response. I also know that C3 and C4 has an affect on the bass response.

Can someone please give me more detail as to how C3 and C4 affect the bass response?

I did a search for "Keeley AND (C3 OR C4)" but I came up with "No topics or posts met your search criteria"[/i] but I think that happened because "C3" and "C4" are too short of a search string (most forum search functions require at least 3 characters to search on).

Thanks in advance.

GF

[Fret Wire]

You should try contacting Robert himself. I'm sure he''l have some suggestions for you. He's always been known for his customer service. Robert recently started posting here. You could email him at his site, or pm him here on the forum.

[vajhoj]

I want to reduce the bass heavy response of my Keeley modded DS-1.

I know I can lower C2 to reduce the bass response. I also know that C3 and C4 has an affect on the bass response.

Can someone please give me more detail as to how C3 and C4 affect the bass response?

I did a search for "Keeley AND (C3 OR C4)" but I came up with "No topics or posts met your search criteria"[/i] but I think that happened because "C3" and "C4" are too short of a search string (most forum search functions require at least 3 characters to search on).

Thanks in advance.

GF

Try changing the R14 to a higher value. I played around with the Keeley Ultra Mod. in my DS-1 - made my own mod. from the basics of the Ultra, but with minor adjustments... Mine is very SRV-like, but with a bit more bite...  

For a low kick try putting a putting a 22K in R1...
/Michael

[jimbob]

I have the same issue. Although I havnt decided if its a good thing or a bad thing. It would be nice to be able to switch from this  extra "bassy response" to a lot less bassy response.

[GonzoFonts]

Thanks for the responses. But I need to make a clarification.

Fret Wire,

When I first read your response, I said to myself "Why would I contact Robert Keeley?" Then I re-read my post…

When I said "my Keeley modded DS-1" is sounded as if this pedal was modded by Keeley. This is not the case. I did the modification of the DS-1 myself (to Keeley specs, of course). Sorry for any confusion.

vajhoj,

I already raised R14. The stock value is 2.2k the Keeley mod calls for 1.5k. I changed mine to 2k. I did not want to raise it more because I don't want to loose any gain but at the same time, I don't want to lower it any more because I want a less muddy distorted sound.

I also lowered C2 back to stock value of 0.47uF. This also helped but I would like to get more distorted grit out of the pedal.

Thanks.

GF

[wampcat1]

If you just want less bass, change c3 to a .047uf, .068uf, or .1uf. The higher the value, the less bass there.

Also, IIRC, change c14 to a .15uf, or .22uf for less bass.

Hope that helps!

Take care,
Brian

[Melanhead]

hmmmm .... I found the same thing when I did my Keeley mod ... It was just to bassy for my rig ...

Here's my mod based ( now loosely ... ) on the Keeley.

http://diystompboxes.com/sboxforum/viewtopic.php?t=32443&highlight=modded+ds1

... sound clips included