Good replacment for BB OPA 2604/604

[safetyman]

Carlos, sorry have not got the time to do it. Gotta pull the amp out of the car and dismantle many many many screws b4 I can get to the chip. Once I get the chance I'll do it and let you know.

Can you be kind enough to explain what the difference will be between parallel and bridging a LM4780? What would be the situation where one would be more preferable than the other?

Thanks and a Happy & Fantastic 2006 to all.

[lineup]

Originally posted by Gasho
Better OPs that have same type of pacage and are double/single version like 2064/604?? Sugestions wanted

I would say OPA2134/134 is a good replacement.
It is JFET Op-Amps.
Price is not too different.

What will you use them for?

[KT]

I have a Chord SPA-1800 preamp that I'm starting to mod.

It has a single ended analog gain stage that's built around the OPA604. I'm going to replace these with either the OPA627 or AD843.

From there, the signal goes to balanced output transmitter which is based on the NE5532.

From there, each leg of the signal goes to a OPA604 before it gets outputed (4 OPA604's at the ouput, one each for left and right + and - signals). I haven't looked closely at this output stage, so I'm not sure if the last OPA604's are in the signal path or if they're some sort of correction servos. I'll probably replace these, as well, maybe with AD843's or OPA627.

My question is, is there a better alternative to the NE5532 for the balanced output transmitter? I've just started researching how this works, so I don't know how much of a factor the opamp is in this position versus an analog gain stage.

Thanks for your help.

KT

[percy]

Reviving this old thread to see if anyone has any comments for the AD8397. Seems to be getting a lot of attention from the headphone amp folks.

[Ryssen]

Is there a single opamp version of AD8397?