Gopher,

Having spent a fair bit of time with NOS RCA-GBs (straight, fat bottle) 5U4Gs, I think I can say that they would likely bring a "splash of seduction" to your Torii. I found some tall bottle ones labeled Sylvania, and some short bottle RCA label on ebay for 25 and 40 (shipped) and both seem to bring texture and open freshness to the midranges and more deep bass compared to the more "liquid" RCA 5U4G-STs. In my system/room, I actually had to slightly EQ out some bass (a very nice, and good sounding refinement feature of the Pure Music software player) and once done, these tubes have become a favorite for me. But I have a history of low bass issues with my Torii in this room.

Anyway, if your low bass is better controlled than mine, you might really like them???

I had a hard time falling asleep this evening, and my girlfriend is at her house tonight, so I started futzing with the stereo and figured out how to add the CSP2 back in using an antique cherry end table that was my late wife's grandmother's, and a Mapleshade platform. I've got 6N2Ps in the CSP2 and one of my spare pair of RCA 5U4G rectifiers and I'm so far enjoying the added bit of warmth and dimensionality the CSP2 always delivers. It's a bit awkward to adjust (the table is behind the Samson rack and the TV stand) and I will have to work on footers, but I think this is going to be a nice setup at least for a while til I can afford another Samson rack, which I think is the ultimate solution to my situation.

It's all just warming up and getting good sound, I'm going to enjoy this tomorrow as it settles in. Thank goodness for music. It sustains a large portion of my consciousness these days.

I'm still experimenting. Right now I am using the volume control at 100 percent most of the time. I aggravated making judgments by doing some tube-rolling.

Lon, you still have the CSP2 out of the loop with your Perfect Wave DAC?
I also have a PW DAC and leave it at 100% output to the CSP2 and then to my Torii MKII.  I kinda like fiddling with the CSP2 levels and the Torii levels to achieve slightly different results.

Think I will run the PW DAC direct for a few days though to experience the sound.  I know PSAudio recommends no preamp.

I have tried the PWDAC both through my Ultra and straight into the Torii. Sounds great both ways. The PWDAC is very good as a preamp. But I like the flexibility of the Ultra, and I am about to start taking more advantage of its tube rolling.

Having said that, I think if I was only driving two channels, I would be very inclined to run the PWDAC straight to the Torii. And the reports of the PWDAC upgrade suggest even greater dynamics, along with the balance adjustability, making it even more suited to being its own preamp.

Like you, I like to see good equipment put to good use. That's why I am glad I found a home for the ZSTAGE. I love that little box, but I just don't know when I would ever put it to use again.

Morgan:

Happy to chime in here, though I will observe at the outset that there are so many variables at work that you may still have some difficulty teasing out any meaningful commonalities. But I am game.

1. For tubes in the Toriis, I currently run Ediswann 6922 inputs, Shuguang Treasure 6CA7 outputs, RCA rectifiers and Raytheon regulators. I love this combo, but I will be shortly trying out Amperex 7308 PQ valves for inputs. All tubes except for the Treasures are NOS. I have some early 1970s Voskhods to try in both the Toriis and Ultra as well. On first test listen, those were quite nice.
2. All types, even some high energy hip hop in small doses. My preferences are for classic rock, large scale classical, e.g., Verdi's Requiem, jazz, fusion, the AIX Acoustica series, good live recordings of all types. For accuracy and tonality, I will turn to the Telarc John O'Conor Beethoven Piano Concertos and the Stereophile Robert Silverman Variations. Sublime.
3.  I am all about the music, but I believe that detail and soundstage are very important to musicality. I value micro dynamics and air that contribute to tonal accuracy. But I don't want the music to sound clinical. Precision in instrument and voice location is very important to me. I can listen to this rig for hours in end without fatigue.
4. Room: I have a mix of a very open room with odd asymmetrical angles, large absorptive furniture, partially reflective walls, and a large plasma display. There is a fair bit of window in the room, but with thermal and acoustic treatments. Overally, somewhat on the reflective side.
5. Preamp: yes, the Decware Ultra running National NOS 6922 valves, an RCA NOS 1964 black plate 54UG big bottle rectifier, and 0B3 regulators, if memory serves. The Nationals are about to be replaced with Siemens Halske 1960s NOS EC88 valves.
6. Speakers: 6 ERRs in a 5.0 configuration. Two of them serve as a center channel speaker with the ribbon tweeters directed at the plasma screen. They are powered by a Decware SE84ZS running in mono.  Bob is working Ina pair of Deathbix DBK212 subs to match the ERRs. They will be sloped in by a Paradigm X-30 and powered by a modified Carver M1.5T.
7. I don't think you asked about sources, but primarily my PS Audio PerfectWave DAC w/ Bridge pulling files from an NAS or Mac mini running eLyric Music Manager, all files AIFF. My transport is an Oppo BDP-95, but I may add a PE Transport just for two channel discs. As good as the Oop and its DAC are, they are no match for the PWDAC.  
8. You didn't ask about power, but I have two PS Audio Power Plant Premier units connected to the Power Port receptacle. All cords are either Decware power cords or PS Audio Statements.

Hope this helps.

Greg