I have built this headphone amp twice. It sounds awesome.
http://www.pmillett.com/wheatfield/manual.pdf
I would like to use a toroidal power supply and go to a solid state rectifier bridge.
If the tube gurus on this forum wanted to go from the 5u4 to solid state, what would the transformer voltage be, and what would you use to clean up the ripple, etc. That is my goal.
Ultimately, I guess I could wreck the sound. What I am trying to do is eliminate the 5u4 and the need for the 5 volt filament voltage. This would allow me to easily find a transformer that would meet my goal. I guess you never know unless you try. I just want to get my B+ just right the first time.