CharlesCThe OP amp in the DAC is a single dual OP amp chip TI OPA2134, and it is soldered permanently. There are two dual OP amp chips (the same) in the A30. They are mounted on a socket, so they are easy to replace. If you are thinking of rolling them, I can recommend Sparkos Labs discrete OP amps. They might be expensive, but the effect is rather stunning.
bigjimThe soundstage gained width and depth, the sound became more natural and detailed. It is not a night and day difference, but definitely took the A30 up a notch and I am really happy with it:
andyoHave you tried rolling the opa2134 with the sparkos? I'm curious to know how it would change sound, and which model number in particular you are referring to.
andyoBy chance do you have any experience between the Sparkos and Burson V5i for the A30? Would it also make sense for me to change the op amp on the D30 to the matching discrete op amp?