Oversampling/Increased dither: a lot of hype?


Is there any clear evidence that longer bit lengths and higher frequency sampling actually improves the accuracy of sound reproduction or does it simply add coloration and superflous "digital noise" that if anything, only taints and distorts the original signal?
I have recently spent a lot of time listening to non-oversampling DAC's (SN Tube Dac being one of them...)and have literally have been blown away by the transparency, the "blacker than black" noise floor and a much more forward and natural sound.
I have to admit that I was extremely reluctant to evan audition the non-oversamplers secondary to all the hype surrounding oversampling. I was absolutely stunned by what these non-oversamplers were putting out...or maybe what they were NOT putting out. It was as if a thick veil of digital noise that I have really heard before was suddenly cancelled out.
Anybody else have similar experiences? If possible, i'd be interested to hear sound arguments for either one.
cohenlt

Showing 1 response by bombaywalla

Eldartford,

Are you quite sure that it's the DAC reconstruction (analog) filter that is responsible for the degraded sound in oversampled/upsampled systems??
I feel that it is the over/upsampling (digital) filter - the one that various manuf. use to do the estimation - that is largely responsible for the degraded sound. By the time it gets to the reconstruction filter, the sound is botched already & the analog filter cannot fix this. Yes, it can degrade it further! However, I still feel that the principal damage is done in the digital domain.
Afterall, over & upsampling were used so that the manuf. could get away from designing a nearly brick-wall filter, which had a transition band from 20KHz-22.05KHz.
It's those estimation (digital) filters that change the harmonic structure of the sound. The algorithms are manuf. dependent & you might like one manuf's & hate another's.

(In the Scott Nixon tube DAC he uses the output tube as a filter by just relying on the vacuum tube's natural freq. response characteristic to low-pass shape the music signal).