Quote Originally Posted by keilau View Post
I finally got around swaping out the OP275 with the OPA2227. But I am not sure that I like the sound better. It seems to sound boomy as my first impression.

I may swap them a few time before I decide. What would be your first choice opamp that can be obtained from DigiKey?
Something that ought to give you a very smooth, musical sound would be these pair OPA627's, (the OPA627 is single opamp, unlike the majority which are dual). I replace the two dual opamps at the I/V stage with Chinese-sourced versions and the result was as described; (buffer stage I left with the one LME49720) ...



I don't think Digikey, Newark, or Mouser sell them. If you want to be sure they are authentic, you could get them from Parts ConneXion, HERE.

Or you could try the eBay, such as HERE, but there is a some risk that they are counterfeit.