antoniosolo
Well-known member
Can I use a TL075 opamp in my Urei without any further modification?
rc4136 opamp alternative for Urei LA4 silverface
- Thread starter antoniosolo
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bcarso
Well-known member
Might work---whether it provides advantages or not is another question.
I hadn't realized until you asked this that TI ever made a 4136-pinout quad FET opamp, but there it is. My first reaction was to think you meant TL074 and caution that the 4136 had a unique pinout. Learn something new every day...
I hadn't realized until you asked this that TI ever made a 4136-pinout quad FET opamp, but there it is. My first reaction was to think you meant TL074 and caution that the 4136 had a unique pinout. Learn something new every day...
C
ClaudeTucker
Guest
I've used a TL075 in place of the 4136 in LA4s. I think it's why I have a few. I don't recall having to do anything else.
It works without changes, but if I remember right it was a little noisier.
Eddie Cilletti has some little boards that take a couple of standard dual SO-ICs and fits them to the 4136 pinout, let's you pick some better newer parts.
Eddie Cilletti has some little boards that take a couple of standard dual SO-ICs and fits them to the 4136 pinout, let's you pick some better newer parts.
jensenmann
Well-known member
JLM audio sells these kind of boards, too
IIRC, it is quieter with TL075, not noisier.
mr coffee
mr coffee
bcarso
Well-known member
If current noise dominates in the existing circuit, it could be quieter with the FET amp.
Well, I just went and looked in the junk box, I have both a TL-075 and an RC4136, one dated 1980, the other 81, which is part of the reason I'm not 100% sure which is quieter, it would've been back then I last had a go at it.
I don't have the time or an easily available LA-4 to try it in, but I would be happy to donate them to the cause if whoever wants to try it out reports back to class...
I don't have the time or an easily available LA-4 to try it in, but I would be happy to donate them to the cause if whoever wants to try it out reports back to class...
jensenmann
Well-known member
I have an LA4 easily accessible but it would be ridiculous to ship an TL075 across the pond to measure it here in Germany. Anyway I´m interested in measuring this stuff since I bought spectra foo at work and seriously need to get into it. This would be a good opportunity to go through some of my gear and learn o use the software. Maybe I can find these chips at my electronics store around the corner.
