Well, I admit I was wrong about tube rolling.
Up until yesterday I've only had 4 tubes for my Crack; Ratheon 6080, Sino 6AS7G, Electro Harmonix 12AU7, and JJ 12AU7.
I had tried the 4 combinations I could do with these tubes, all of which sounded relatively similar, so I kind of ruled tube rolling as being audiophile BS and wishful thinking.
On a whim I looked into RCA clear top 12AU7s and found a good deal for a strong tube for only $10. I figured why not try it? This is the tube that always seems to be described as an affordable jack-of-all-trades-master-of-none.
I have to say this tube fixed some issues that I had noticed that I didn't realize were being caused by (or at least emphasized by) the new production 12AU7s I had. The RCA tube smoothed out this weird distortion I was hearing in the upper mids or lower treble that sounded like static or a glassy grating sound. The RCA also sort of bumped and rounded the bass a bit. Enjoying my Beyer DT880s even more now.
I wouldn't say the sound has drastically changed like you read on other forums where people go on a long tangent peppered with pretty words about how the sound could save the lives of starving children in Africa, it's not
that drastic of a change, but its enough be noticeable and improve the listening experience and I'm all about that.
Pretty cool!
Just thought I'd share the moment I had my tube epiphany.