So my question is - is there any other method to determine authenticity of lossless file? Any software tool that uses better algorithm than auCDtect, or just different algorithm tuned specifically for detecting HQ AAC transcodes?
Sometimes listening to the SIDE channel signal of mid-side encoding (i.e Left - Right sample values), will reveal lossy encoding effects, as can using very clean but extreme EQ to try to de-mask the varying quantization noise at certain frequencies. However, even that isn't definitive, especially with the number of legitimate DSP effects around, some of which will leave signatures that would be fully masked in normal listening (especially de-noise algorithms).If you think you've found one, I guess you COULD post a short (<30s) lossless sample from a certain time in a certain track and ask for people with the CD version to bit-compare or upload the equivalent section of a CD release for comparison in compliance with the TOS.
Because someone revoked TOS and I think he said about TOS#8 (ABX-ing) I have to explain something. I am not trying to find transcodes because of my "golden ears" (which I don't own - I hear quiet but constant hiss above ca. 14~15kHz).