[supertron421]

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[supertron421]

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[steven_1026]

http://www.overclock.net/sound-cards-computer-audio/718389-opamp-changes-xonar-essence-stx.html
 
You would switch the OPA2134 with your new opamps. They can be a little hard to pull out, small pliers would help but I've always just used my fingers and wiggled them out. Be careful if you wiggle them, don't wiggle too much or you might damage the connectors.
 
Oh and make sure they're oriented the right way. Use the dot on the opamp as reference.

 

[alien3456]

The image in the above overclock.net link shows and identifies the opamps perfectly. The only thing that wasn't obvious to me when I replaced mine was how much pressure is required to get them out. Don't try to pry them out with a screwdriver or anything; you can and should get them out with your fingers. Just pinch the black part by its bare sides and pull directly up, wiggling a bit.
 
Should be obvious once you get the new opamp and have your sound card by itself.

 

[jackwess]

You can also use a chip puller (they are available on most electronic stores) to remove the old opamps. 
 
Keep us posted. 

 

[supertron421]

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[steven_1026]

Quote:

Would I have to worry about replacing that center op amp (which is a buffer op amp from what I've heard) if I'm only outputting from RCA?

Nope

 

[fzman]

Quote:

Nope

other way around - the buffer is very much in the analog rca output path

 

[ROBSCIX]

All three opamps are used when you are using line outs.  Only the rear two (I/V) opamps are used when you are using headphone outputs.
In the above picture, the OPA2134's are the I/V and the other is the buffer opamp.
Great picture BTW!

 

[steven_1026]

Quote:

other way around - the buffer is very much in the analog rca output path

Whoops I knew that!
 

 

[ROBSCIX]

When you switch to headhones mode, the buffer opamps is switched out of the circuit and replaced with the headphone amplifier chip.