What set of measurements can be performed on 2 DACs such that if the two sets of measurements were identical, we could accurately predict that nobody could tell them apart in an ABX test?
Clever, but I’m looking for a serious collection of measurements.
This is where I want to get to, though:
If we have 2 "validated transparent" DACs, one selling for $299 and one for $29,999, is it fair to make the claim, based on science, that the $29,999 is over-priced snake oil that sounds the same as the one for $299?
Is it true that given 2 DACs have equal Noise and Distortion measurements, we can predict that they are indistinguishable in an ABX test?
And if someone can create a DAC with SINAD < -115 dB that can be reliably distinguished by ABX testing, then we need new measurements.
@BDWoody So now my question becomes:
Is it true that given 2 DACs have Noise and Distortion measurements below -115 dB SINAD, we can predict that they are indistinguishable in an ABX test?
I understand that on this metric (SINAD), they *should* be indistinguishable to human ears.
And if this is the only measurement that matters, they will be indistinguishable to human ears. Provable through ABX testing.
But are there other measurements that we're missing? We need a falsifiable hypothesis to conduct science, right?
The hypothesis then is: Given 2 DACs have Noise and Distortion measurements below -115 dB SINAD, we can predict that they are indistinguishable in an ABX test.
And if someone can create a DAC with SINAD < -115 dB that can be reliably distinguished by ABX testing, then we need new measurements.
Consider a device constructed from a low-noise high-Q 1kHz sinusoidal oscillator. The device takes a PCM input which it rectifies and LP filters to well below 1kHz, which is then used to set the amplitude of the generated 1kHz tone. This device would score very well on the DAC SINAD test despite the fact that it's not a DAC at all! You need at least a frequency response test and probably also the IM distortion test to show that a device is even a DAC.So now my question becomes:
Is it true that given 2 DACs have Noise and Distortion measurements below -115 dB SINAD, we can predict that they are indistinguishable in an ABX test?
And if someone can create a DAC with SINAD < -115 dB that can be reliably distinguished by ABX testing, then we need new measurements.