Well, it's funny how one thing leads to another. A discovery by accident.
I was tube rolling in the Modwright TP. The new PS upgrade (hyper-drive) adds a considerable amount of weight and authority to the sound, and therefore a different set of tubes pre and post upgrade. The 6H30 DR's just couldn't coexist in both the TP and the 36.5, and I'll be damned if I move them out of the 36.5
(note: in fact, other than the stock 6H30's and some other plebian variants I'm not sure there ARE other tubes to roll in the 36.5 signal section). So there i went tube rolling the signal tubes in the TP, (posted on the TP tube rolling thread...duh).
David (Rydenfan) and I chatted today about the 36.5/TP combo possibilities and he mentioned that maybe a solution would be to wait until I had a pair of higher end 5AR4's for the 36.5 and then pull the metal base out of the TP and use a GB there. (I currently use a pair of the very nice and airy Tung Sol 5U4GB's in there, and my 5AR4 inventory is made up of single versions) Hmmm....got me thinking. I DO, in fact, have a pair of very hi-end 5AR4's...the frickin metal bases!!!! BIG problem though; one of them died, or more accurately, dies frequently, while placed in the TP. But I never tried it as a second half of a pair to use in the 36.5. Maybe the current/voltage in the 36.5 is different, or maybe it's just a TP socket thing. yeah right. Well....Worth a try I guess.
I found it, pulled the other MB from the TP and set them in the PS 36.5....grabbed a black base Mullard 5AR4 and put it in the TP, and flicked on the switches. We have dual metal base liftoff!!! In fact, the TP 5AR4 was not lit, but a little jiggle and it was back in business (I think I might have a slight issue with the rectifier socket in the TP and maybe that's all it was with my "dying" metal base).
The combo of three 5AR4's was nice, a musical extravangza with nice prat (best I've ever had). The only thing missing was a little air I was used to in the soundstage depth. So I swapped out the TP rectifier and went with David's suggestion...the wonderful TS 5U4GB. YES!!!!! AND IT COUNTS!!! (Marv Albert voice). Wow! Best sound yet. Wow! (Did i say that before?) Overall, after all this, my soundstage just took a leap forward in prat, depth, air, musicality, detail and what i call "wetness" or organic qualities (acoustic harmonics sounding like acoustic instruments in the room, etc.)
Thank you, David, for the suggestion....albeit not aware that I would act on it so quickly... cuz you and I assumed I had no viable pair of 5AR4 candidates. Oh yes I do!!