OP07CP for ProCo Rat?

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OP07CP for ProCo Rat?

jaredcohen
I've been looking around, and with the prices of the LM308 (which might be fake on eBay anyway), it seems people really like the OP07DP in a Rat.  Looking around, the OP07CP seems more easily available (aka Tayda has them).  For better or worse, I trust Tayda more than eBay at this point.  From the datasheets, the C and D variants have really similar specs, with difference in "CMRR (Min) (dB)" and "IIB (Max) (pA)".

Comparison: http://www.ti.com/product/OP07C?keyMatch=OP07&tisearch=Search-EN-Everything#parametrics

I have no idea what either of those parameters mean, though.  Just wondering if anyone's used the OP07CP, or has a more knowledgeable opinion as to whether it will work before I order a few.

Thanks!
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Re: OP07CP for ProCo Rat?

rocket88
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You don't have to worry too much with stuff on eBay, you just have to buy from someone with a good track record. I'm putting a rather large order of IC's and I used to order a lot from g_cmarket, and polida2008, but g_cmarket has recently sold poor, defective, or seemingly couterfeit/fake IC's to Miro, and Polida2008 for shipping can take forever. I haven't gotten fakes from g_cmarket, but I won't order from them now because of what happened to Miro, and polida2008 I may order from as I haven't had any problems with them. There's also el-parts that I've had good luck with too, and there are a few others I "follow" that are reliable.

I've also, been reading a lot about how to spot fakes, and counterfeits because it's always in the back of my mind. When you look at the pictures avoid the ones that look like they may have been sanded or have a different texture, or the print looks off, or the tooling markings (holes and such) look to have been filled. Also, if they are beyond cheap compared to all other sellers, avoid, don't even think about those ones, as there's a high probability they're fakes. When you get them in inspect them for the same issues, and try one in an effect that you know works and how it should sound to test that they are good. If not, report immediately to the seller and eBay, both tog at your money back and to being it to their attention as it's illegal and eBay does take action.

But, I can tell you from the rat I built for bass, I originally had a normal lm308 in there, and if sounded good, but have since switched to a NOS lm308ah metal can style IC and it sounds smoother, and less fizzy. But, then again I have Ge diodes in place of the normal Si, and changed some of te resistors in the gain stage that act as a filter as well.
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Re: OP07CP for ProCo Rat?

jaredcohen
Thanks rocket... see that's why I'm skeptical.  Everyone has difference experiences.  I bought a bunch of 2N5457's from polida and every single one is useless.  I guess I can risk it for a few 308's though.
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Re: OP07CP for ProCo Rat?

rocket88
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Well, I would look elsewhere then. Checkout el-parts, every IC I've seen them list looks legit. I'm not sure about polida anymore either, same with g_cmarket. I might not make my big order from them either, one of the chips they list is sending a red flag to me the more I look at it. There's more and more people around here saying they got bad parts from them, so they might not be a good place anymore. I'll see some of the others I have in my saved sellers list if you want.
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Re: OP07CP for ProCo Rat?

Luke51411
I don't know where you are located but if you are in the US you should check out mklec.com they have LM308s for around a buck a piece. I bought 10. I've only used 1 so far but its working great! They have decent prices on a few other things too, mlcc caps, pt2399 and probably some other stuff too.
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Re: OP07CP for ProCo Rat?

Frank_NH
You can also try a CA3130 in place of the LM308.  I recently purchased a bunch of CA3130s from eBay for cheap.  I love them in the BJFE/Bearfoot circuits.
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Re: OP07CP for ProCo Rat?

kirshman
I can second mklec, both their website and eBay store.  Bought several things from there and always been satisfied.