DAC's : The missing feature: Signal quality

If it sounds good, it is.I use a retro rotel RDP 980 and it does make a difference.

S/N 110dB, THD 0.0025%.

Depending on your budget Ifi Audio has a Usb -3 purifier$129 a steal,  that 
removes 40 dB of noise , plus regenerates a totally new signal 
parts qualityexcellent , they also have  productcalled the defender buy 1-2 removes crap associated with computer noise $59 computer switching  tons of High frequencygsrbage  both come with full
money back satisfaction , also there AC purifiers at $99 I have 3 
i have great isolation dedicated lines, Copper audio outlets 
good line conditioning and these AC purifiers are cumulative. 
Plugin line conditioner , and AC outlets . Many people usethem
Abbington music - UK is the mother company.
they have a headquarters in theUS. No risk ,Results or full money back . I am a Amazon prime member shipping is -0  even on returns something to consider if buying .  Go to IFi audio cite 
best bang for the $$ out there IMO.

Todd -
I didn't know they had that! That's pretty awesome.

E

audioman -

The issue there is the same. I’ve read technical reviews on iFi purifiers that show them to be a really mixed bag. They don’t do enough to control power supply noise, and end up just moving noise from one area to another. See if you can find it on google. Lots of charts and measurements in it.

The problem for us consumers is if there is an audible change, we don't really know which is better. What if the purifier, or digital cable is actually awful, but we buy it because it sounds different?

I'd rather have some way, built into my DAC, that tells me. Like signal strength meters or tuning centering meters on old FM tuners.

Best,
Erik