Best DAC

op

to answer you

1) i am not a computer streaming expert (i use a dedicated streamer) but as i understand it it is the whole computer that generates electrical noise, not just the drive ... the computer has many elements that are not optimized for noise suppression in conveying data through its usb output for hifi music (you may want to search youtube for john darko videos on streamers and computers, he is easy to understand yet also complete with his explanations)

2) yes any dac translates conveyed bits back into an analog signal fed into the arc tube preamp, yet all dacs do so with a certain ’voice’ and ’tonality’ - just like a phono cartridge does with the grooves cut into a record ... your tube preamp does add some warmth to the signal fed to it, but only to a degree... if the signal fed into it is too lean, treble centric, ’digital’ sounding, it still won’t sound too good coming out of the preamp with its mild, flattering coloration ... the trick is to find right balance - the job of a dac is not just to ’dredge out detail’, it is to make the bits sound like real music again

of course this depends so much on one’s taste... some listeners are detail freaks who like a ’hyper-real’ sound, some value natural tonality as one would hear in a live unamplified voice/guitar or jazz or string quartet performance... there is detail but it is conveyed within a context of warmth, dimensionality, wholeness, naturalness of tone

good luck have fun

the arc sp-6 is a fairly honey colored unit (a good thing) but with decent high end extension and an expansive image (i used to have one many moons ago) - you did not mention which version you have... of course you can roll the 12ax7’s or 6dj8’s inside to shift more or less honey colored

of the dacs mentioned so far which i have tried i would break into the following groupings - for your benefit in system matching for tonality

smoothest/most analog/warmest mids-midbass: mhdt, audio mirror, a-n - bear in mind these dacs can have tonality tuned with tube choice as well

slightly brighter: denafrips, schiit mb (gumby and yggy)

brightest/leanest/’fastest’: rme adi2, mytek bb

others to consider which are exceptionally natural sounding and great sq for $ -- metrum and ayre codex (fitting in 1st group), ava valve dacs (second group)

you should get a usb cleaner if you plan to continue to stream from your computer - that is the source and my bet is that is a source of deleterious noise into the system along with the originating digital signal

otherwise buy a dedicated streamer such as a bluesound node 2i (use it as a good cost effective streamer only, and not as a dac although there is one on board ... it is poor)

then consider outboard dacs... search - there are many threads on good dacs fitting various budgets