MACKIE PPM series 808M Service

[TAC]

I'm servicing a MACKIE PPM 808M that channel 1 doesn't work but channel 2 is just fine. I've determined the input op amp (U3A - NJM4560M), is bad. This is the input op to the power amp board from the mixer board. Of course the part is obsolete. Anyone have any recommendation on which of the following similar parts I should use as a replacement?

NJM4565M
NJM4580M
TLC272BCPS

Also, how important would it be to replace the good NJM4560M input op amp on channel #2 with the same new op amp part number that I'm using in channel #1?

[drewl]

Any standard dual opamp should work fine, 4558 through 4580 or other designations.

[Jon Snell]

The 4558 is very similar and readily available.
There are plenty of 4560 about at different suppliers but not worth chasing.

[g1]

Also, how important would it be to replace the good NJM4560M input op amp on channel #2 with the same new op amp part number that I'm using in channel #1?

If you are worried about matching the 2 power amp sides, I don't think you would ever notice a difference.

[Jon Snell]

If you are worried about matching the 2 power amp sides, I don't think you would ever notice a difference.

The gain and response is governed by external components, not the IC itself in most cases.
There will be no measurable differences.
The 4560 will work hapily on +-4volts, that is why it is a choice for active pickup use in guitar pickups. The 4558 needs +-6volts minimum and as you have +-16volts available, not an issue.
The noise and open loop gain figures appear to be the same.