Looking for excellent DAC without a preamp section

There are lots of great choices. I would recommend that you audition the Perpetual Technology gear (P-1a, P3-a with the Wright mods and the separate Wright power supply). Easily under $10,000 -- way under!! Sounds great, has received fine reviews. Meets all your criteria though I can't confirm the 2 volts out.

Others to consider are the Audio Note and Naim (if I recall, the older Naim 5's, but I may be misremembering).

I think that there is a Muse 296 for sale right now at about 12% of the price you are talking about. Upgradeable to 24/192 status as well.

Audio Synthesis DAX discrete doesn't have preamp section also Meitner DCC 6 doesn't either also the Meitner DCC 2 has a output which bypass the preamp section

I love my Musical Fidelity Tri-Vista Tube DAC. It outputs 24/192 or 20/96 with a switch on the back of the unit. It also has a digital passthrough and accepts SPIDIF and Toslink inputs. Great sound IMHO although I have not compared it to any other DAC's. Price is $2400.00 new. Not sure if there are many still available as it was a limited run.

How about the Dodson or Audiologic DACs?Any feedback?

The Weiss Medea does not have a preamp portion and the Theta Gen VIII is available without it.

Why care if the DAC has a variable output? You don't have to use it, and at unity gain the output stage is not really in the picture (to varying degrees). Most high end DACs do have a variable output.

Why discount a Meitner DCC2 or Wadia 27ix because it has a variable output? Especially something like the Wadia 27ix where the volume control is digital. At 100% volume, it is the same as no volume control. Being "out of the picture" may not be entirely true for DACs with analog volume controls.

Few standalone DACs do not accept 24/96 inputs. It is easy for them to do as most of the off the shelf chip sets support it. What is hard to come by is a 24/96 source.

Also, I hear Wadia has a new DAC coming out.....

I know there will be a lot of EMM labs recommendations (for good reason), but would suggest you should be sure to audition some of the most recent Audio Note DACs too - the latest generation (especially 4.1x) are exceptionally musical and are my own personal choice - for the $0.02 that's worth... The latest will be unfortunately hard to come by used but are a significant step forward in extension - particularly at high frequencies IMO.

In this range, there is a lot of great gear out there, so it becomes a matter of tastes and system priorities I think. Regardless, you shouldn't wind up with any glaring compromises regardless of which aspects you prioritize (assuming the selection is more recent I suppose)... so enjoy!
Jacob

Add to your list the Muse Model 192 DAC (a 24/192 DAC). Only about $4000 or so new.