opamp decoupling, and biasing

[audiokid25]

1)Ok, heres my question. Im swapping out the opamps in my dvd player which are currently 4560's. Im using AD8620's. Ive attached a image of the circuit. Shouldnt the PS decoupling be the same for the +8 and -8? They are using 100uf for the +8 and 100nf for the -8. Shouldnt these be the same value?

2)What would be the best value to use as decoupling with the 8620's?

3)What is the best way in this circuit to bias the 8620's into class A?

Thanks

 

[AndrewT]

Hi,
that does seem odd. Do they know something about how that filter is consuming current?
Is there room to fit IC coolers to the chips before you convert to ClassA?