I finally threw together some pictures and posted them on my website. The url is:
http://homepage.mac.com/butterworthfam/AudioDIYLast night, I performed a little bit of tube rolling with the 12AX7s. This is what I noticed.
1. My stock tubes were Tung-Sol 12AX7 new production. These sounded good in comparison with my very cheap solid-state phono. The bass was strong and solid, highs were clear, etc. In other words the Cornet2 sounded great.
2. I swapped these for old Telefunken 12AX7s. They are not matched and the sections are possibly not balanced. However, in terms of sonic clarity, they beat the Tung-Sols. The highs were cleaner and crisper, but not harsh. The bass initially sounded weaker, but really it was less boomy. My wife described the Tung-Sols as muddy in comparison with the Telefunken.
3. Old, used GE and an old used Amperex (Bugle Boy) 12AX7s. Both made in Gt. Britain by Mullard, and probably of the same era. Anyway, we liked these the best. Where the Telefunken was a little shy in the bass, the "Mullards" were warm smooth, but not boomy like the Tung Sols. The highs weren't as crisp as the Telefunken, but still exceptionally clear.
Anyway, I am not going to go into a great deal of detail on the tubes, as I am unskilled in this sort of thing. We used the original vinyl of I-Robot by Alan Parsons for our comparisons.
I describe on my webpage that the 12AU7 is the input tube and the 12AX7s the output tubes. Is this really the case, or the best way to describe their roles in the Cornet2.
Finally, my website is under construction and I'll be adding more photos and diagrams.
Regards,
Charlie
