There's no such thing as an audibly perfect DAC, is there?
Yes, there is - look at all the DACs in the blue and pretty much all the green sections of the chart here.
When the imperfections (noise distortion and frequency response) are so small that the human ear is not capable of detecting them - so audibly perfect
Our ears have neither infinite sensitivity, nor infinite bandwidth.
They don't all sound the same.
If you have two dacs that are audibly perfect (and a majority of modern ones are) then they must -by definition, sound the same.**see below the line of ******** at the bottom of this post for more detail on this.
In my (subjective, unblinded) listening 'test' I had no difficulty in immediately recognising that the iPower2 power supply made a substantial improvement to sound quality in my system, it wasn't subtle.
I'm not surprised. In unblinded subjective listening tests there are all sorts of things going on in your subconcious brain that will alter the sound before it reaches your conscious brain. This is not a criticism - everyone's brain is doing this all the time - it is how we are built - it helps us to function.
Assuming the devices you are comparing are half way decent, if you tested blind, and controlled (including accurate level metching) I am confident those unsubtle differences would evaporate.
Do you mean the Wiim Pro, or Pro Plus? I've heard the analogue out (DAC) of the Pro and it's extremely poor, the analogue out (DAC) of the Pro Plus far superior.
Yes, I did mean the pro+... BUT: the pro, like the mini has a sinad of around 90dB - while this is not guaranteed inaudible for everyone, it is for the vast vast majority (in blind tests the vast majority can't hear -45dB distortion - let alone -90dB). Purely on a statistical basis the odds of you being one of the tiny minority who can hear the difference is vanishingly small. If you are over the age of 30 I would say zero. Most likely the reason you hear it as worse is you have read that it measures worse, and your perceptive biases ensure that is how you hear it.
**********
** A DAC has one, and only one job, and that is to accurately convert the digital representation of music from the source into an analog representation of that music. Well measuring DACS do that with inaudible levels of noise and distortion, and with flat frequency response in the audible band. In other words the analogue output is (audibly) a perfect representation of the digitally encoded music.
If two DACS both achieve this (and well measuring DACS do) then the analog signal from both must be identical within audible limits. By definition, they must sound the same.
Or at least, assuming the amp and speakers are the same, will result in identical sound waves reaching the ear of the listener. What the listeners brain does with that sound information, and how it mixes in the environment, expectations of the listener, mood of the listener etc etc to "colour" the
perception of that sound has nothing to do with the performance of the DAC.