Boss CE-1 Op Amp Sub

Started by nickbungus, November 21, 2017, 04:22:58 AM

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njkmonty

ive put the mn3007 on hold as i have enough mn3002,, once depleted will look at implementing the oo7

willwaush

I'd like to give the 3007 a try just because I'd like to get it to work with it. I also have enough 3002, but it would be really interesting to try the 3007 solution. So, as far as I understood the thing to do would be halving the clock capacitors? And it didn't work for you because you had clock noise with those, right? What could be a possible solution and where could that clock noise come from?

zombiwoof

Quote from: ElectricDruid on November 21, 2017, 12:46:03 PM
I don't think changing the circuit is difficult. Just drop all the frequency compensation stuff and voltage bias and keep the basic feedback paths.

In terms of replacement op-amp choice, I agree with you nickbungus - a bit of grit is a part of it. For this reason, I'd go with something more old school than a TL072, like a 4558 instead (basically two 741 type amps in the one package). But you could try other stuff from a similar era.

I suppose you could go for 741's themselves (with no advantage in terms of board space) and then you could keep the freq comp capacitor too!

HTH,
Tom

It is my understanding that the 1458 is the dual version of the 741, the 4558 is a later chip with improved frequency range.  I know that one of the mods for the modern DOD OD250 RI pedals of a few years ago was to replace the 4558 (they were only using half of it) with half of a 1458, easier than modding the pedal to accept a 741 and essentially the same thing, only dual.
Al

njkmonty

i tried it only for a short period of time, just out of curiosity, and havent put that much effort into it