In the era of high-resolution digital music downloads, classical music collectors are often confronted with a confusing array of formats and sampling rates within formats. One eventually learns about the different sampling rates available for PCM releases, and does his best to make an informed decision about which one has the best sound quality for his requirements. For legacy classical releases which have been marketed as "remastered" at a certain bit-depth and sampling rate, one generally expects his purchase to reflect what was advertised. Unfortunately this may not always be the case.
Are some record labels essentially repackaging redbook-CD-resolution data as high-resolution? A friend of mine and I have consistently raised this question about a number of recent digital releases from "Alexander Bak Reference Recordings" and "Praga Digitals" on Qobuz. But most recently we may have discovered an Australian affiliate of music titan Universal doing the same. I make no accusation here, but simply lay out our analysis for you to decide.
Here is the spectrogram of the first track from Henryk Szeryng's Beethoven Violin Concerto, recently released from Universal Music Australia on Qobuz. You can see the truncation of the Nyquist frequency between 22kHz (RBCD) and 24kHz:
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Beethoven: Violin Concerto (Hans Schmidt-Isserstedt Edition 2, Vol. 1), Ludwig van Beethoven by Henryk Szeryng - Qobuz
Some might argue this is could be 24/44.1kHz data, but then why use 48kHz? Attempts to contact Universal Australia for inquiry have been unsuccessful. We did contact Alexander Bak Reference Recordings, who chose not to disclose their sources (though larger labels routinely state if original sources were used). At best this is misleading, as Universal has the resources to provide true high-resolution music. We've found other questionable examples from Universal Music in Japan, who distribute some 24/192 releases which appear to have been downsampled from DSD (SACD) releases, when the mastering studio uses 24/192 for the working master (in the interest of keeping this article brief, I've omitted this spectrogram with tell-tale, out-of-band noise from a recent purchase of mine).
For collectors who've bought the same releases multiple times over the decades, and believe these distinctions are significant and audible, one solution is to buy only a track and analyze it with the free Audacity editor. Ideally, labels would disclose what they're doing.