From what I can tell I am looking for the answer to what appears to be a fairly common problem.  

I am interested in getting as much bloom/saturation as possible in my music at low listening levels.  I know that their are limits of how much detail the human ear can hear at low volumes, but I know that some amp speaker combos give more bloom for lower volume listening.  

My gut is that the 2 wpc Super Zen Triode paired with the Betsy open baffle speakers might be the answer.  Maybe I am a bit backwards though.  Maybe the amp needs to feel a load to give more current, so maybe the Super Zen Triode paired with the DM945 so they have to work a little harder?

It does seems like a SET class A amp would be key for my goal here.  

If memory serves I remember watching a paul mcgowan video where he says that every amp has a sweet spot.  I.E. when the volume pot is turned to a certain level it performs the best.  

I listen in a relatively smallish room so I hate having to turn the volume up to get bloom from the music.  I don't want to listen that loud to get as much detail as possible!

Thanks All!

John

Which ever amp you end up with include the ZR2.  I had the UFO2 and it was excellent for low level listening.  I now have the UFO25 and I consider it an end game solution, in a league of it’s own, low level, high level, mid level, doesn’t matter.  My system includes the CSP3 but I don’t know if you would need it.  Start with one of the ZEN UFO amps with the ZR2.

Here, here. I would recommend the ZROCK2 as well.

I would think you would put together a system with low gain as one factor. Which then relates to the volume control. Resistance volume controls convert unwanted signal to heat, and as you use lower settings you are throwing away more signal to get low volume. That's going to affect the sound. Many say the very best volume control is a TVC or transformer volume control, or similarly AVC autoformer volume control. Those are expensive and Decware doesn't use them as far as I know. So with Decware you would want an attenuator. You would look for low gain so to get your desired volume, you would turn the attenuator up to near the max setting. Then most of the signal is passed through and not thrown away. That would also mean using speakers that will be at the desired volume with the attenuator turned up. Finally lower volumes roll off low and high frequencies, so something like a ZROCK2 as mentioned is designed to compensate for that. All those factors combined in a system should sound better than other systems at low volumes.

I probably play about 80 percent jazz. . . maybe more. The rest is classical, Brazilian, funk, blues, sixties and early seventies rock.