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Senior Member
Username: serialnumber12

Post Number: 921
Registered: 12-2004
Posted on Saturday, October 01, 2011 - 4:48 am:   Edit Post

anyone with knowledge on this please chime in too..... part# rc4136db its the chip in my bass question is can it be replaced with chip/part#276-1711 lm324 Quad op amp? .....please give me a call if possible at 224 392-9838 keavin.
Advanced Member
Username: jimmyj

Post Number: 306
Registered: 8-2008
Posted on Saturday, October 01, 2011 - 8:35 am:   Edit Post


I'm not smart enough to know if those amps are interchangeable but my uncle Google warns:
"... the LM324 pinout is not the same as RC4136. 4136 has an oddball pinout"
which means you would need to have an adaptor socket of some sort or actually remove some traces and jump the circuit board... Big job, for small hands and good eyesight! How the amps themselves compare or might work in the circuit is beyond me. Hopefully somebody else will jump in here..

Jimmy J
Senior Member
Username: keith_h

Post Number: 1706
Registered: 2-2005
Posted on Saturday, October 01, 2011 - 4:26 pm:   Edit Post

The RC4136 is still available according to the TI website however the type of package it uses has changed. The old package format was called SIOC and the new format is call DIP.The pinout is the same according to the datasheet I read.

They make adapters to allow a 14 pin dip to plug into a 14 pin SIOC location. This is something that needs to be done by someone that is knowledgeable in electronics and fine soldering. The cost of the parts should be minimal.

Senior Member
Username: dfung60

Post Number: 516
Registered: 5-2002
Posted on Sunday, October 02, 2011 - 6:54 pm:   Edit Post

Keavin -

You can buy a RC4136N at Mouser Electronics:

It's only $1.30 (probably $7 shipping, so buy a bunch).

This device is a really generic op-amp.

You actually quoted the RC5136DB which is a slighly different chip. It looks the same, but is a surface-mount part where the "legs" don't protrude through the PC board. These parts are designed for robotic assembly. If the chip you're looking to replace is soldered directly to the PC board, then it's possible that this is what you want, but if it's in a socket, then you almost certainly want the 4136N. If it's directly soldered, you'll need somebody with specialized experience to replace it.

If this is in Alembic #12, then you want the 4136N to replace the socketed amp.

Keith did a good job sleuthing. I think he meant "SOIC" layout, which is actually a newer package than the DIP chip that's in your bass, but was obsoleted first. The guts of this sort of chip would have just been buried inside a bigger chip in the modern world, but the old-school discrete ICs (e.g., chips that have just one function in them) often outlive the newer parts.

Take a close-up picture of the chip you want to replace and we can determine for sure.

David Fung
Senior Member
Username: keith_h

Post Number: 1707
Registered: 2-2005
Posted on Monday, October 03, 2011 - 6:11 am:   Edit Post

Yes, I meant SOIC. I've always had issues with my fingers not doing what the brain tells them to. :-)

It has been a number of years since I've read any datasheets. I left electrical engineering for software back in the early 80's. Prior to this I had dabbled some with bass guitar preamps. I still have one in my 76 Jazz Bass where I use a Signetics NE5532.

I found a picture of the electronics on the Old#12 thread and I see what appears to be a 14 pin DIP in a socket mounted to the bread board. It would be better to get a close up to get a clearer picture of the chip. If it is in a socket then the RC4136N is all you need as Dave says in his above post.


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