Hi again.
I have been working with diff amps a la Allen Wright and promised to return when I have made some more work on it. Before I write my stuff a lot of thanks to all the helpful people here on TubeDiy Asylum.
The schematic below worked out fine: 
This sounded very well, more details, better bass, more dynamic and so on.
I have a few remarks. Poul Joppa pointed out that the negative supply should at least be in a size equal to (mA though CCS) x (resistance between cathode and CCS) + (min. voltage that make the CCS work). In my case it is 66mA x 101 ohm + 5-10V = somewhere between -11.5 and -15.5 V.
The second remark are that Allen Wright somewhere here on the Asylum writes that the current difference between each half of the output transformer shoul be less than 1mA. In my case it was easily done. My output tubes was matched so there where 3mA difference. With the balancing arrangement on the schematic it is posible to adjust around 5 mA between the tubes. But in other cases it may not be enough. They drifted around 1.2mA in 3 weeks.
I used a LM317 as current source in a previus version. It do not sound good, which a lot of people told me and they were right.
So what! My intention was to use the pentode part of the 7199 as a CCS, but then I added another diff amp as driver instead. Again with a single ended input. The schmatic is a bit ugly:
Again the sound was better, more details and clear sound, a bit more "fast". A few new problems; a pop noise when the CD stops, a little noise when I turn the volume knop. A bit of hum in one channel.
Still I miss some of the SE magic to some records and time at day. (Billie Holliday and good redwine at night to give you a clue) Maybe two power amps in the system is the only solution.
I still work on the Dynaca-SCA35 original pcb. They are starting to fall apart, so my next project is a major rebuild with better parts, new tube sockets and so on.
If anyone have good ideas I would appricipate that. Else I think I wait for Allen Wright's PowerAmp CookBook before I work more with my amp.
Regards puff
P.S. I still impressed with the huge difference in the sound from changing the schematics but still mostly reuse the same parts.
