Please Help replacing HA1457 with OPA604

i have these amps (Sony TA-F6b, Kenwood KA-405, JVC JA-s44)with faulty HA1457's that need to be replaced with OPA604, which components from the existing boards should i add, change values or completely remove for it to work properly? here's the schematics

sony.png
jvc.png
ka405.png
opa604.png
 
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However you fit them you are going to have to re arrange the pin outs.

Just stick to the rules of using normal opamps. It looks like you will not need the compensation networks connected to pins 3 and 5 so that means in the Sony that R208 and R209 and C202, C203 and C204 can go.

Same for the JVC with its network to pin 5

C11 on the Kenwood.

When you power up do it first with volume on minimum and check the opamp output is at zero volts.

Use a scope to check for stability but the OPA604 (make sure they are genuine) is unity gain stable should be fine.
 
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