Quote Originally Posted by a0r0a7 View Post
I have now replaced the opa2134(s) with opa2107(s) in my sd1955+ DAC. The opa2107(s) are not cheap but not as expensive as the opa627, in the Uk £30 for two opa2107 from RS Components. I can advise that the opa2107(s) have given the sd1955+ a more natural detailed sound. The bass is more defined but not quite as deep as the opa2134(s) sounded. The highs are sweet the midrange very much the same. I can also tell an improvement in the soundstage a little, its wider.

To sum up my SMSL SD1955+ is now as far as I wish to upgrade, I am very pleased with the results. Some might say upgrading the power supply (Teradak 9VA) and OpAmps (2 opa2107, 1 opa2604) is false economy and they are most likely right but I have enjoyed the tweaking exercise and improvements along the way

cheers
Andy

HAPPY 2014
Happy New Year to you too, Andy

Yes, the opamp swapping exercise was a lot of fun and a good deal cheaper than, say, swapping interconnect cables. With more discernible results too I'd say.