First Watt F8, passive preamp, DAC

@johnk 

Yes, I definitely see the wisdom in that approach.  I heard a loaned Nelson Pass D.I.Y. First Watt S.I.T. Paired with my Coincident Statement Line stage (101D tubes) and it was exceptionally good sounding. I do understand that the goal per topic is however  DAC direct to amplifier.

Charles 

As I type I am running the same DAC with the volume at about 1:00 (so roughly 1.0V output?) into my preamp at 14db gain into the SIT-3 with 11.5 db of gain.  1V output with 25.5db of gain is plenty on my 94db speakers.  I typically listen around 83-84db average, so pretty loud.

The OP's scenario could "possibly" work BUT...

System gain is still 10 db less than yours. Not insignificant.

DAC voltage is 1.44 vs 1.8.

His speakers are 3 db less sensitivity than your 94 db.

Perhaps cutting it a bit close it seems.

Charles

1 Speakers are 91 db sensitivity.

2 Amplifier has 15 db of gain.

3 No use of an active preamp.

4 Desire to use DAC with volume control direct to amp.

5 Definitely a high voltage output DAC is required. With this scenario probably at least 4 to 5 volts or higher.

Charles

1.44v is pretty low.  Most DACs output 2v and higher. With that low voltage coupled with a low gain amplifier, unless your speakers are high sensitivity, you’ll likely need an active preamp to provide additional gain.

Charles

The DAC output is 100 ohm unbalanced, 200 ohm balanced. I guess that's pretty good. 

Those specifications (In ohms) are referring to the output impedance. What is the output "voltage" of your DAC?