Running DCS Vivladi DIRECT?

my listening levels for the tracks were between 9.5dB and 14dB cut on the DAC

I'd try the 0.2V output setting on the Vivaldi if you attenuated between 9.5dB and 14dB; this way you'd be able to run the volume control to max, with no more than 5dB of attenuation.

Why do you need to match the output level between your DAC and phono stage? I mean, are you doing on the fly changes between inputs on the preamp while listening simultaneously to your TT and DAC? In that case the Vivaldi would be quieter than your phono stage at the same volume level on the preamp.

The 0.2V setting on the Vivaldi might sound better when run direct into the amps since you'd hardly get to use the volume control at all, keeping it mostly at max.

If you attenuate between 9.5dB and 14dB on the Vivaldi with the 0.6V output setting going direct, running 0.2V into the preamp won't need its 12dB gain at all.

Using your preamp you first attenuate the signal from the source and then amplify it back to the level required for your listening anyway, since you're forced to apply the preamp gain to the signal no matter what. (the gain stage in your ARC preamp is fixed not variable like in Ayre's preamps btw)

If you have a TT you need a preamp anyway and it's irrelevant to the discussion what output setting you prefer on the Vivaldi through the preamp for various reasons; the discussion is about differences between DAC direct vs preamp and I think the Vivaldi direct should be used in its optimal configuration to the amps in question, for the result to be as meaningful as possible.

My take is that if you wouldn't prefer the Vivaldi direct on its 0.2V output setting to the preamp route, you don't really like how the DAC sounds and prefer the coloration/enhancement that the preamp gives you.

Sorry, but you're confused.

If you keep the volume on the Vivaldi between -9-14dB for a -20dBFS signal, the volume level on the Vivaldi will still be at -9-14dB for a 0dBFS peak signal. The attenuation level stays constant irrespective of the source's signal amplitude, the same attenuation level is applied to a -20dBFS signal and a 0dBFS signal.

-20dBFS signal + 9dB attenuation = -29dBFS signal
   0dBFS signal + 9dB attenuation =   -9dBFS signal

So you always listen at -9-14dBFS peak levels.

Keeping the volume between -9-14dB on the Vivaldi for the 0.6V setting means the output level is too high.

Yes, to have some range to go louder above the "comfortable listening level", but if the max SPL you listen to has the volume control always set at -9-14dB then the 0.6V output is too hot.

Here’s another way to look at it, maybe this way you’ll get it:

0.6V @ 0dBFS = -2.21 dBu
0.2V @ 0dBFS = -11.76 dBu

Now apply 9dB of digital attenuation to the 0.6V signal, you get:

-2.21dBu - 9dB = -11.21dBu = 0.21V

So whether you use the 0.6V (with 9dB of digital attenuation applied) or the 0.2V (with no digital attenuation) output setting, the DAC outputs the same voltage basically at 0dBFS.

Aside from the 0.2V  output setting for the direct connection, I'd also toggle between the different filters available since the one you prefer when listening through the preamp might not sound the best when going direct.