improving ic's eg jrc4556d

[awpagan]

i am a proud owner of a philps cd850 (think mk2?)
and am trying to mod it mainly for headphones.
Simple upgrade would be replace analoge phono output, replace opamps they are single jrc4556 on separate phono driver pcb,
uprade two jrc5534d in audio output.
I have a good idea what the 5534's are but the 4556, dual opamp
sounds right but no info on web for jrc components
any refer to these was the RA-1? but stated they are high current
Not really good for my headphones Beyer dt880's
any suggestions

ah also
since the headphone driver is on a separate pcb, i could replace the
pcb with a full class A driver stage

I've seen plenty of posts for upgrading the cd850, seems popular,
but first time in forums of any kind

anyone have shematics or service manual for this?
would also like to mod digital section

last question
is digital out coax or spdif before any digital mods or after being
if i use external dac will it circumvent any digital mods

[macboy]

The data sheets that you are looking for can be found at the NJM (aka JRC) website .

[awpagan]

thanks macboy for comfirming they are same opamps.

To change opamps or not to change opamps

there are a lot of different views out there