Originally Posted by aats
You can't prove that
I can prove that anyone reading this, such as yourself, is incapable of hearing a difference in a double blind Foobar ABX test I post, listening through whatever gear they want (and can get their hands on).
In addition to the degradation my iphone's DAC imposes on the digital file (the song), there are additional possible stages of degradation which may occur (and if they are not also transparent then they should make the listener's task of trying to hear a distinction, of any kind
, between song file A and file B even easier
- the cheap, analog RCA wire coming out of my phone's DAC, going to my cheap ADC
- the cheap, outboard ADC used to convert the analog sound back into digital
- the cheap USB cable which the now digital signal travels through to my laptop
- the recording process in my laptop to place that incoming digital music stream onto my hard drive as the new file.
The test of Tiefenbrun shows how to test the transparency of a DAC [and all the peripheral devices/wires in the chain] using an originally analog
source ["Disc" means vinyl LP]:
My test is similar however since my test instead uses a digital
master source the positions of the DAC [labelled "D/A" in the above diagram] and the ADC [labelled "A/D"] are flipped. Also instead of using a hardware A/B/X switch box the free software version, Foobar ABX, is used since we are now comparing a master digital file to a recording of that master source file after it has gone through a chain of (possible) degradation.