HDCD rescue - it's possible, but man...


I spent the better part of today sick, but working on finding a way to decode music I might have that is HDCD encoded.

As a refresher, HDCD was an enhanced CD format. In some ways the predecessor to MQA. HDCD was an engineer's toolbox, allowing the mastering engineer to select a number of features. This would then be decoded by a matching chip on a CD player or DAC. The most famous feature of HDCD was bit-compression. Getting a 24 bit signal encoded in a 16 bit music file.

As an aside, the Pacifics Microsonics AD converters were highly prized by engineers for their sound quality. Anyway, the format got bought by Microsoft and died.

Of the 670 CD's I have ripped only about 11 were HDCD encoded. But man, what a pain. I ripped everything to FLAC, but the HDCD decoder only does WAV. I had to download source, compile it, then write a script to go through every CD and decide if it's HDCD or not. Once found, I have to convert from FLAC (44/16) to WAV, decode the WAV file (now 24 bits) and convert back to FLAC to compress again.

The discovery process was pretty fast.  About 10 minutes to go through them all by cheating. :) More time was spent figuring out how to pass apostrophe's in file names than finding the files.  Nathalie Merchant was one author who consistently used HDCD by the way.
erik_squires
georgelofi

it appears to be a "gold" CD. These always fetch a little more at auction.
it appears to be a "gold" CD. These always fetch a little more at auction.
Yes it is gold.
What perplexes me is that both the HDCD version and the non HDCD version came from the same one off recording session.

Not that I'm a recording engineer, but they (the studio) must have done this recording master using two different methods, HDCD and Non HDCD??? Is this correct???

Cheers George   
@dtc

I'm sure the mistakes were honest. :) I only meant to point out that many think they've discovered unmarked HDCD disks (like a bonus track on an album) when in fact they are plain-Jane Redbook CD's. This is probalby why they don't have HDCD branded on the covers.

Best,

Erik
Hi @ptss

Well thank you kindly. I was very fortunate to be able to observe a true master, Dr. Marshall Leach Jr. when I was very young. That exposure sparked a life-long interest. My humble memorial to him is here. Later on I was able to work in circuit board and industrial design for motion picture sound systems, before digital sound for film existed.

While I have an interest in many things, my main focus right now is achieving high-end movie and music sound for apartment living. Meaning small and affordable but not quality limited.

Best,


Erik
I agree -George,
different mastering (codex) methods for the HDCD moniker.
I find a more interesting aspect, in that, there are HDCD discs that are not "branded" as such.

In the early 1990's before the big "remastering" boom in 1994 and forward to this day, there are plain CDs of various titles/genres that were "remastered" and not branded as such.  Weird or testing the waters by studios and record companies?