Chip swap for a Tone Pump?

[bigal]

Has anyone tried different ICs in their Tone Pump? Care to share any insights?

Thanks!

[plan-x]

I liked a stacked 4558.

[bigal]

Interesting- what kind of effect does that have?

I tried some different chips in my DD a few years back but never did the chip stacking thing. I remember liking a Burr Brown chip (2604 I think?) in the DD. If I remember right it was a little clearer and had bigger bass response. I ended up going back to the stock chip but it was fun to experiment a little without doing any damage to the pedal!

btw, is there a sonic difference between the 4558D and 4558P chips?

[plan-x]

The 4558 stacked I made would give it a little more girth, bottom, fullness. The stacked chip would do more for this pedal than all the chips I tried. But I'm not sure about the Burr Brown OPA2134, that chip also has a noticable change above all chips. I don't know if there is a difference in the "D" or "P" designation on the 4558's sound. I read yes and I've read no.

[hamerman]

I have two DD (mod board and standard). One always has a Burr-Brown in it for a more hi-fi overdrive. I particularly like it in the mod board DD. The other will have the stock chip or one of the common subs. The LM833 is a nice choice, but the stock chip is great too.

[bigal]

Cool. I'll have to get an LM833 and give that a shot. I have a few other chips around here that I'll toy with.

Plan X- to stack chips do you just solder one chip on top of the other?

[plan-x]

Yes, but be careful not to fry the chips. Quickly, without overheating them. They will still work with heating damage, and sound crappy. You can buy em too from somewhere. David use to sell em.