any ideas on what these artifacts are in Qobuz stream (captured)?

[fatoldgit]

The album stream sounded a little strange so I captured the output (via a Slimdevices Transporter into my pro Denon ADC recorder with the capture via the digital outs/ins respectively).

The stream is 44.1/16 and as the Transporter doesnt upsample (which is a plus in my opinion) the capture path is bit perfect.

The album is from 1975 so before the recording chain/mastering would have involved digital devices (?).

It has obviously been digitized from tape but I wonder what the artifacts are at ~9.5k, ~18k and ~19k

We also see no HF energy above ~20.5k but that might be due to limitations in the original recording chain or the digitization process?

I doubt the artifacts are any kind of water marking.

Thanks,

Peter

 

[Daverz]

You often see continuous tones like that in CD spectrograms, though having one under 10 kHz does seem unusual. Cutting off at a little above 20kHz is also not unusual in older recordings.

I was just looking at this spectrogram of a recording from the 90s

From a New Albion CD:

 

[fatoldgit]

agree on the older recordings not always hitting 22k.... but many I have looked at from the late 50's achieve that (taken from tape masters obviously).

Maybe early'ish CD releases done with a full DDD chain fail the 22k "test"?.

I have also seen single continuous artifacts in CD spectrograms but this puppy has three (though one could conclude that the ~9.5k and the ~19k) are related.

Would really like to understand what these are. They dont appear to be audible.. but you know.. paranoia and all that!!!!

Peter