Lol I'm no genius as I'm sure most people here can tell ya!
The Procedure
The original digital file. That would be the gold standard - that a person could listen to on their current DAC. It should be made accessible.
Then use a high quality ADC (which has been tested) to record the best measured DACs followed by DACs which measure in lower tiers.
So 120db DAC. 115 db, 110, 105, 100, 96 (CD quality), 90, 85, 80, 75, 70 and 65 (if any can be found).
To take it a step further - if there is a way test it with a combination of an amp and DAC recorded.
Try to level match the recorded levels if possible before recording.
The music could be two categories- one a regular popular piece of music. The other an acknowledged well recorded piece of music that has low distortion in the parts of silence and a good dynamic range preferrably one available in higher resolution. If desired the third piece of music could be a vinyl rip just to see what the threshhold is.However, It mustn't be different pieces of music used with different dacs. Stick to the same choices of music samples over a wide range of dacs for consistency.
Optional: Obviously these categories could be expanded to include genres like heavy metal, electronica and classical if one desires but not necessary since it could be time consuming. A piece of music that appeals to me is to also have some music made with stereo microphones in a low noise non close miced environment - one with no alterations made to it.
It seems relatively straightforward. This could be incorporated into standard testing that Amir does.
The main limitation here I think would be Amir's time. It does take more time to hook these up and run these tests especially with combinations of equipment. But it doesn't have to be Amir. If it's somebody else, the limtiation would be time, equipment, as well as a confirmed high quality ADC. Maybe they could send in their ADC to Amir to test if the measurements are not already published.
What use would this be?
The whole point of this is to allow users to see for themselves what significance the measurement variable of SINAD has when choosing a DAC to them. It's good to quantify exactly how significant listening to less than 110db SINAD is for music use. I am unaware of any studies done on ASR for music. The reason I was given is "what music is the standard?" But it also means I haven't seen any data.
I've seen multiple threads where new buyers come and basically show me that they are using the SINAD chart to entirely base their decisions on DAC buying. They would ignore a DAC with 105 db for a 120 DB DAC.
Some may ignore DACs with useful features like processors like the Emotiva XMC-1 which doesn't get even near 110 db but offer tremendous flexibility like room correction and bass management because of worry of the "sonic impact". So knowing what one is actually getting when looking at SINAD is useful.
How would they do this:
It would allow people with very high performance dacs and/or amps to test for themselves what significant sonic effect (if any) they would encounter if they used a worse performing DAC (for SINAD).
They could perform double blind tests with them and post results or any impressions they care to impart. People with lower performing dacs could look at the results and impressions of these tests and form their opinions.
If a 100 people with a benchmark dac were unable to hear any difference between the original digital file and a DAC recording at 80 db in a DBT, I think that would be some good evidence.
Also people with lower quality older dacs - say one at 95db SINAD may be eyeing a dac upgrade. But if they listen to a 80 db DAC and still hear no difference, then they may wonder why they would want to upgrade their current DAC and focus on what else may be causing dissatisfaction. Perhaps it's their rooms or their speakers which are much more likely to provide larger distortion.