I'm probably not going to make anything out of this, but a new web-dl has appeared of something never physically released.  My old version, while still 1080p is inferior in video detail... except the old Dolby 5.1 audio track is 384kbps, while the new one is EAC-3 5.1 at 256kbps.
I'm not great at understanding spectrum analysis, but to my eye, the old version should be superior.  How certain can I be of that?
I'm open to opinions.

OLD:

NEW:

The old one has more information, and a higher bitrate, but something odd is happening at about 16 kHz in the old file -- a strange frequency especially from 30-35 minutes.
I assume they both sound fine but the old version might have a little more detail. The only way to be sure is to A/B the two and just listen.

Wait. I vaguely remember reading a post or article somewhere about source errors (conversion from analog? old hardware?) causing lines like that in the spectogram.
That's gonna bug me.

You can manually remove them in Izotope RX or something like it.

I think that when E-AC3 bitrate goes to 256 Kbps and under for 5.1 mixes, it cuts off at around 15-16khz, and the difference is Unaudible to the Human ear. Here is an example from a rip of American Ninja Warrior which has a bitrate of 192 Kbps 5.1, and it cuts off at 15khz.




   

(2022-03-05, 02:48 PM)Doctor M Wrote: Wait. I vaguely remember reading a post or article somewhere about source errors (conversion from analog? old hardware?) causing lines like that in the spectogram.
That's gonna bug me.

It's found in any analog conversion/recording that was done near CRT monitors, they emit that frequency that ends up in the final audio and only younger people can hear it. I can't find the discussion about it, must have been on Originaltrilogy.
I found this though https://hydrogenaud.io/index.php?topic=77743.0

Like Lio said, it has to be removed with softwares such as Izotope.

Any audio editing software with a notch filter can remove the CRT line. Obviously when CRTs were the predominant display tech any artifacts in the audio would have been masked by the audio emission from the display itself, I must say I've listened to many a laserdisc at volume and not been aware/distracted by it

I usually take a good strong CRT line as a sign that a mix has not had any heavy NR applied.

A CRT line would be constantly horizontal, right? OP's thing is jumping between three different frequencies.

It should be constant but who knows how many variables come into play when dealing with analog media.