This Thread has introduced me to a good variety of suggestions across a broad price range on DAC's that are available, some at very attractive used purchase values.
I would be very confused if I were attempting to produce a shortlist, there is very little way to learn about the Sonic models suggested are capable of.
It does seem the OP is needing to receive demo's of a few types of DAC in systems with hopefully other ancillaries that are quite popular in use. By making it known what type of DAC and System was used for the Demo's, creates more avenues to receive comments on experiences had by others.
The follow up reports that can then be offered, these will certainly jog memories and help others who have had a similar encounter, which may have resulted in making a decision on purchasing the DAC demo'd, or alternatively discovered something else to be more attractive / or more of a repellent. This type of exchange of info, is one that prompts, experiences can be called on and the supply of ones thoughts/recollections on the impression that had been made are able to be offered with a useful and dependable description.
I would certainly want to know what the Sound being produced is like, prior to releasing the $3.5K - $5K funds. Nobody can describe a sound to the way a listener is to perceive it, this is a seat in from to the device experience only, I do not know any other method to accurately evaluate.
I feel confident, that if the OP was to sit down in front of my CDT>Bespoke Built Valve DAC > Bespoke Built 845 mono's > Modified ESL Speakers, they would thoroughly enjoy the experience, to the point where they have been very influenced by what has been shown. The complication with this is that the whole system is bespoke, and not understood by non-listeners, resulting in little help being forthcoming.
After the dust settles, there is always the 'but' moment, as the Honeymoon Fades and the reality appears, and it realised something that was uniquely important to them from a produced sonic, failed to manifest just as they like it.
As an Old Friend, now deceased used to inform me in jest, " when she starts farting in the bed, you now know the Honeymoon is over".😏