HD Certifier

Origin
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I tried out the Origin’s HD Certifier for the first time today. Here are a few results:

  1. I recently purchased the 24/96 download of The Flower Kings’ Back in the World of Adventures remaster. Some people had speculated that the original recording from 1995 was done with 16 bit digital technology. Sure enough, the HD Certifier noted that the frequency limit was just short of 22khz and labeled it a “Dubious HD Recording” with a bandwidth that was “Not HD”. However, the HD Certifier does claim that the bit depth is HD. Can anyone explain the significance of that last finding?

  2. Rush’s Moving Pictures was one of the first albums to be mixed with digital technology, which was 16 bit. The hi res version were allegedly created by transferring the digital master to analog tape and then converting the analog playback to 24/96 or 24/48 digital. This makes all hi res versions of the album fraudulent. However, the HD Certifier gave readings of “Confirmed HD recording” to both the Sector 2 version and the 40th Anniversary version. Perhaps it was picking up noise from the analog tape and interpreting it as music? The Sector 2 version, which is a 24/96 download, had a sharp drop off at 22 hz, perhaps indicating the end point of the original recording.

  3. I looked at the title track from Molly Tuttle’s recent Crooked Tree album, an all digital 24/96 recording. It came back as a “Confirmed HD recording” with frequency response up to the expected 48 khz.

Has anyone else here been using this tool?

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:notes: :eye: :headphones: :eye: :notes:…

Bit Depth defines the ‘Dynamic Range’ of a PCM recording… It is calculated as: 6db x (number of bits) + 1.75, where: (1-bit = @ 6dB)… ‘Bandwidth’ or ‘Frequency Range’ is defined by the Nyquist limitations of the Analog to Digitization process (A/D)… An analog-tape recording typically has limited dynamic range (Signal to Noise) and frequency response and these factors determine what may be analyzed by the HD Certifier from any given “Master” file… It is difficult to know what the origin of older analog to digital transfers are coming from, because many older analog master-recordings were digitized at 16bit/44.14kHz… Today there are high-resolution products derived from analog-tape master recordings but they are generally limited by the digitization process… Warner Bros. had the myopic business decision of digitizing their entire catalog of analog-tape masters using 24bit/96kHz and 192kHz A/D mastering… Others take it further, like this label: 2xHD that produces DXD and DSD products from archived analog-tape masters…

2 Likes
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Thanks for the info. So, if the HD Certifier says that a recording has HD bit depth, does this mean that the dynamic range exceeds the limits of a 16 bit recording?

The new Flower Kings remasters are allegedly remixes. I’m wondering if they could have exceeded 16 bit dynamic range for the master even if the track tapes are 16 bit.

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:notes: :eye::headphones: :eye: :notes:…
16bit,20bit,24bit/44.14kHz or 48kHz is considered “HD” …

“High-Resolution” PCM is in the realm of 24bit,32bit/88.2kHz, 96kHz, 174.6kHz, 192kHz and DXD 352.8KHz, 384kHz, 705.6kHz and 768kHz…

Direct Stream Digital (DSD) is a one-bit “High-Resolution” encoding scheme using Delta-Sigma A/D sampling at frequencies of 2.8MHz, 5.6MHz, 11.2MHz, 22.4Mhz and 44.8MHz (DSD64, DSD128, DSD512 and DSD1024)… Bit depth is irrelevant in DSD as the encoding scheme records amplitude and time in every sample representing a signal more akin to analog signal voltages.

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:notes: :eye: :headphones: :eye: :notes:…

The resolution of any given PCM “master recording” is defined by the frequency of samples (Fs) and the bit depth… a 16bit/44.14 or 48khz master can be up-converted to, or, ‘interpolated’ to a higher bit-depth and sampling-frequency… for instance 24bit/88.2, 176.4kHz, 24/96kHz, 192kHz or to DXDxxx… that same master-file can be remodulated to DSDxxx.

Edit:
How a 16/44.1 or 48kHz master is “re-digitized” depends on factors like: was the remix ‘mastered’ to digital or back to tape? These days it makes little sense to remix to tape, when we have DXD and DSD as archival formats.

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Thanks again.