• WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required as is 20 years of participation in forums (not all true). There are daily reviews of audio hardware and expert members to help answer your questions. Click here to have your audio equipment measured for free!

Watermarking: what do we know?

111MilesToGo

Member
Joined
Nov 18, 2020
Messages
5
Likes
12
Addendum to my post #56 above: I did now compare purchased (in 2018) tracks from four download stores, HighResAudio, HDTracks, Acoustic Sounds, and Presto. I couldn‘t find any difference between any two stores to yield a null all over the frequency band. Very bad result given this is all purchased music!

I will try three approaches when my time allows:
  • If mattmontag is correct in saying (April 2020) that all UMGs are clean now, one can hope that the stores replace their files. I‘ll check whether a store allows me to re-download those older purchases of mine. But then, how to find out whether I‘m getting a clean copy now?
  • I might check how a purchased downloaded CD quality file compares to a dBpoweramp AccurateRip of an original physical CD. The AccurateRip fingerprint or the flac audio checksum will be the easiest things to do.
  • The most difficult thing to do with DeltaWave will be to evaluate the difference between a purchased downloaded hi-res file and its physical CD rip. Most of the time, those will be different masters; and even if they are from the same mastering, it might be challenging to align them perfectly.
I will report back. Happy to receive hints and recommendations from you.

Remark: I did not look into streaming services (yet).
 
Last edited:

adam2434

Member
Joined
Apr 28, 2019
Messages
58
Likes
42
Not sure if this is the best place to post this.

Does anyone have the interest and capability to take a CD FLAC rip and the same FLAC track on Tidal and capture/compare the Chromecast Audio digital output bitstream for both.

One would have a make their best educated assumption that the CD and the Tidal FLAC track are from the same label release/master by looking at the label, release date, etc.

If the two bitstreams from the Chromecast Audio are identical, then I think one could assume that the Tidal FLAC track is identical to the CD and that the Chromecast Audio is passing it bit-perfect.
 

Katji

Major Contributor
Joined
Sep 26, 2017
Messages
3,002
Likes
2,200
hmmm, @sajunky particularly concerned about this. ...No longer around, neither here nor there...

Everything you stream is watermarked, It doesn't depend on the streaming service, but a label supplying a stream. Some labels use very robust method, it is designed to survive MP3 compression, so is audible.

In addition, they frequently fail to dither properly when converting from hi-res format to 16-bits, resulting poor tonality and harshness on the top end.

Most of downloaded content is also watermarked, it also depend on a label. If doubt, read the Amazon T&C, they mention something (in a slightly obfuscated way).
 

Belker

Member
Joined
Feb 20, 2021
Messages
41
Likes
78
Location
Sweden

sarumbear

Major Contributor
Forum Donor
Joined
Aug 15, 2020
Messages
4,445
Likes
4,003
Location
Southampton, UK
Do any of you know what app would have been used to create this spectrograph? I might be onto something more with being able to look at watermarks.

SvFhJav.png
Audition has similar view
 
Top Bottom