[bigshot]

Could alias noise be louder than the signal itself?

 

[gregorio]

Could alias noise be louder than the signal itself?

It’s not just noise, it’s also specific frequencies (alias images). They’ll be the same level in the audible band as they were in the band above the Nyquist freq, they’re mirror images. So although typically low in level (because the ultrasonic content recorded is typically low level), it can have audible effects if the frequency of the alias image/s conflicts with the musical content.

And, if there is relatively high levels of ultrasonic content (for example pitched metallic percussion instruments) the alias images can have an audible effect even if the freq of the images happen to match the frequencies of the musical content.

G

 

[bigshot]

I doubt it would amount to much in the real world. Probably inaudible almost all the time. There are better reasons to not use MQA than that.

 

[gregorio]

I doubt it would amount to much in the real world.

Depending on the music/sound, it can make an audible difference, it’s not so hard to ABX. But how much aliasing MQA allows through I don’t know, I’m sure it’s probably reduced to some extent but whether that’s enough to still be able to ABX I can’t say. I would guess it’s probably around the threshold of audibility and therefore may not amount to much for most people. I doubt they would have allowed it on the market if the distortion was fairly easy to ABX.

G