Matching up speakers and amps

The Acurus can probably be improved upon. You didn't give us a budjet to work with. As a generic answer I like what tubes do a lot and have them in almost every place I can. What sound are you aiming for? An older ARC piece may be affordable to you, they typically clean up your sound, as they say precision instruments or something like that. If you want a little more warmth an old Conrad Johson or even a Cary. I like the Cary because he uses 6SN7s in his (tube) designs.

Sorry, I should have mentioned I am budgeting around $2500.00.

Based on reading about the DNA 0.5, & having one in one of my systems (with Spendor S3/5 SE's), I'd keep the McCormack--very nice sounding amp, unless you have very hard-to-drive speakers perhaps.

PS--what are you looking to do, i.e. what's bugging you about the sound now, etc, that you want to improve?

A possible upgrade for your McCormack DNA .5 is to try and score a used DNA .5 that has been upgraded by SMc Audio. Sometimes you can find them here on A'gon for about $900- $1000+. If not you can send it to SMc Audio for mods. Whenever I've spoken to Kris or Steve they always are willing to customize the mods to your needs and give you the most for your buck. To me if you are happy with the McCormack just stay along those lines.