Jim Lesurf wrote:

Eeyore wrote:
Marky P wrote:
tony sayer wrote:

I Wonder how may pro recording bits of gear are around with
5532's..

Just about most of it in current use.

Are they at all similar to 5534's? Sure I used them in a phono
pre-amp in the 80's, copied out of a R. A. Penfold book.

Yes, they're the dual version and about 3dB noisier although not quite
sure why.

Not knowing why, my immediate suspicion was substrate noise caused by
having two lots of bias currents. But that is just a spur of the moment
guess. :-)

FWIW I came to prefer the HA12017 as a general purpose audio op-amp. But I
appreciate this is quite a weird choice.

Weird isn't the word for it. ;~)

Ever come across NJM 4560s, 4580s or 2068s ? From JRC/NJR (New Japan Radio
Company). Not at all bad and the 4560 doesn't burn as much current but is a bit
noiser than 5532s but still around TL07x levels.

Btw - don't EVER confuse the NJM4562 with the LM4562. Someone dropped a minor
clanger there and I think it was National, why is why the same device
(apparently) turns up as the LME49720 as well.

Graham