I have a Rolls RM203x mixer that recently took a power surge and lost
the left channel. Opening the box, I saw that it was full of BA4560 op
amps - 2 for the mic preamp, 1 for each of the 9 stereo channels, 2 for
the preamp output, and a couple other for things like the effects loop,
etc. I swapped some of the op amps and was able to get the left
channel working (though it then took out the channel from which I
swapped the op amp).

While searching online to buy some replacemet BA450s, I came across
people saying the NE5532s performed much better in various other
devices (mostly mic preamps) and that it was an easy swap.

Does anyone know if it truly is easy, ie. I can just put the new chips
in the DIP sockets? Should I do it for every BA450, or only in the
output stage? For the cheap cost of the NE5532s, I'm willing to
experiment.

Thanks for the advice!

Mark