Could bass be added into this by adding a larger input or output cap?

[jimbob]

for my ce-2.

[jimbob]

OK- I might have figured it out. Maybe. I noticed that I placed a 398k reisitor in r 38 instead of the 150k. I found a 160 so I say thats close enough and see how that works. Also I have a .68uf instead of the .47uf for C2. I wonder what difference that will make.

I had been having problems with speed being too subtle and not much base. Ill have to see if this change above made any difference.

Anyone, know if .68uf instead of the .47uf for C2 makes any difference .I dont have any .47uf's and the board is already tight.

http://www.tonepad.com/getFile.asp?id=101

[jimbob]

So I tested it and now it has more speed, so obviously the 150k versus the 39k I had in it makes a difference. I'm still not sure if having a .68 versus a .47 makes any audible difference. It still sounds a little thin. Maybe its my amp, guitar, ect.

[Mark Hammer]

Increasing that cap from .47 to .68uf won't really do all that much.  C2 and R4 already provide a low-end rolloff at just over 7hz (!).

The only thing I can think of is that somehow you've maybe neglected C15/R23, or perhaps inserted the wrong value for C3/R5.  Those two combinations provide a pre-emphasis/de-emphasis network to serve as a kind of poor-man's Dolby B.  IC1a serves as a unity-gain stage for most of the frequency range but C3/R5 (6n8, 10k) provide a gain of x5 for content over 2340hz.  This is offset by C15/R23 which provides a complementary symmetrical treble cut on the output stage. This way, it brings the tone of the delay signal back to the original bass/treble balance, while further attenuating any hiss or HF whine picked up along the way after the pre-emphasis.

If the matching of the pre-emphasis and de-emphasis is off (and I simply mean use of same nominal value components, not "matching" to 1%), then it is possible the tonal balance might strike you as a little bright for your tastes.  There IS a little bass-taming (C5/R8, and C10/R15) in the delay path, but not enough that you'd notice unless you were using it for bass through 15" speakers.  If C1 or C17 were incorrect values you might lose some low end but they'd have to be off significantly, because the stock values provide VERY little bass cut.

[jimbob]

Thanks. Ill check it out.

[jimbob]

It turns out that I had C2 and c3 switched. I also found c16 was a .0068 instead of the required 100pf. It sounds great now! Just like my commercial Ce2.

Mucho Thanks Mark!!

[Mark Hammer]

Congrats!

This strikes me as yet one more reason why Dave Bales' tip about ironing on a parts-placement guide is very clever AND useful. http://www.diystompboxes.com/smfforum/index.php?topic=48098.0

In fact, it might be helpful if people developing projects (such as GGG or Tonepad) included not only a PCB and parts layout image in their pdf documents, but a reverse image of the parts layout the same size as the PCB pattern, so that one could iron it on to the component side of the PCB and avoid the sorts of mishaps that jimbob has experienced here by having iron-on legending for the board.

[jimbob]

Wow-I hadn't seen that thread. That is a great idea.