I purchased a soundtrack disc from eBay and have archived it on an external HDD as FLAC/CUE.

However, when I checked the spectral dispay in Audition I found it looked, well, 'strange'.




I'm not sure whether the disc was produced from a lossy source or not. The noise at 19-22kHz looks dubious.


Is this a lossy sourced disc or just dodgy mastering?

You'll need to zoom in. Try a one-second window and from 14kHz up.

Okay, here you go - 1s window, 14kHz and upward.




Is it me or are those blocks that are characteristic of lossy files?

Yep, looks lossy to me.

Thanks for verifying that for me

Someone is gonna get a nasty email tomorrow

Also looks like computer monitor bleed into a mike, or something of that sort.

Do you think someone recorded the original files (maybe mp3) through line-in, maybe from one PC to another? Producing that 'noise' between 19 and 22Hz.

You're right, there's also an element in the recording that wasn't sourced form lossy.

"Unfortunately" more and more people become convinced that lossy coding can be transparent or at least of very high quality. As a result we see an increasing amount of supplied lossy sources for subsequent cd/film/etc. mixing and mastering. A lot of people don't know or underestimate the risks of processing lossy audio, so the best advice for those involved in the audio production chain is to stick to lossless as much as possible.

The really prominent frequency line is at ~15,75khz, which is NTSC hsync frequency. IMO the files you have are an analog recording from TV (or close to a TV). Modern computer monitors wouldn't have such a low hsync frequency.

There you have it. I didn't think the whole time that this was lossy compressed, the HF range looks much too virgin and the >20 kHz band is just normal quantization and/or dithering noise. The only thing I hadn't yet an explanation for was the 15,75 kHz line. And that's really NTSC's hsync frequency!

I hope you haven't written that email, yet...

I've purchased a pressed CD on eBay that was sourced from lossy. Orbital's Blue Album. The telling detail was that there was no publisher or catalog number information anywhere on the CD. The track listing was identical to a bogus scene release that included several tracks not on the official album.

I think it's had noise reduction applied.

While there's probably a TV involved, I reject the idea that this is an analog recording from a TV or close to a TV. You'll see that the 15.75 kHz line is broken in places (just prior to transient events). This makes a strong case that it was part of the element that is lossy.