CD Format Cheat Sheet

Edits in Bold. Thanks everyone!

I wasn’t able to find a concise listing on this forum of the various cd formats so I’m posting this here. If it’s wrong in any way, please let me know and I’ll edit accordingly. If someone else already did this an my search skills are just rubbish, please lmk and I’ll edit accordingly.

Red Book - the normal Audio CD format. Search CD Rainbow Books for context.

Gold Discs - manufactured using gold instead of aluminum for the shiny “B” layer. Gold doesn’t make things sound better, it just makes the shiny layer less susceptible to degradations called perforations. Occasionally platinum is used.

SHM /Platinum- Super High Material discs upgrade the materials used in layers A,B, & C of a traditional CD making the product less susceptible to perforations caused by light getting through the thin layers of aluminum. Sometimes they use Platinum for the shiny layer and call that out to market against more costly and far less common Gold these days.

Bluspec & BS2 - manufacturers write to cd discs using a different laser developed by Sony for Blu-ray discs. This doesn’t change the quality of the sound, it simply reduces manufacturing errors inherent in a traditional cd pressing process and therefore improved margins for manufacturers or at least a nice little royalty for Sony.

HQCD - another manufacturing technique that aims to reduce error correction which is an intellectual exercise at this point as it doesn’t make any difference to sound quality due to built in error correction mentioned before. Simply put, longevity due to material upgrades (platinum, etc) started to plateau and they rebuilt to process of manufacturing cds thus gaining an edge in pressing/read error reduction. Super cool in my opinion but purely a material / manufacturing quality exercise with no bearings on sound quality as the amount of information on the Audio CD hasn’t changed.

SACD - Requires special equipment and/or software and another little royalty to Sony. The SACD layer sounds different from the Red Book layer as it’s a different mastering since the format holds a lot more data than a CD. SACDs often sell as hybrids which contain both SACD and RedBook masterings. Why wouldn’t I just buy a red book cd for $10 if I’m not going to listen to the SACD encoding you might ask. Read on! This format is a little weird given Blu-ay exists but it’s still popular with nerds (me) who have the old equipment and don’t want a Blu-ray player.

Many original releases are being made available in new masterings which is to say choices the original master made might have been limited due to the source files she had access to or even the mastering tech in the studio. New masterings are often from the original tapes and they have more tech now so theoretically they can produce a more accurate representation of the original sound. They can also just reduce drum reverb and sell it for more money. Your ears will be the judge. Occasionally, a new mastering is released only on a new format such as hqcd or even an SACDs redbook layer and that’s why one might buy and SACD just for the new redbook master which is otherwise unavailable. For fun, one can often find a remastering available only in Hyrbrid format in the US on redBook CDs in Japan for less money. Same mastering and therefore the same sound. It’s a very cheap way to get certain white label MoFi masterings.

Hopefully this saves you some time and money. Happy listening!

 

It's ok, if it ever comes into question, I will vouch for your CD Format cred.

 

I don't mind at all if Japan wishes to experiment with variants of the standard CD format ..... SHM-CD, Blu-spec, UHQCD, Platinum etc ...

They still have an interest in the future of the humble CD, so for that I give them a big one of these

 

XRCD is also Redbook format. JVC uses a different mastering process.

 

DSD is PCM lossless so is CD audio whats your point there the same thing. Now a uncompressed wave file that is different

 

DSD audio is not PCM, thus single-layer SACDs do not belong in CD lineup, IMO (only hybrid SACDs do).

 

The question was about whether or not I could hear above 20 khz. My answer to that is relevant to the question.

 

What about HDCD?

 

Easily ripped this using an older version of EAC (Exact Audio Copy Version 0.95 Prebeta 3) that still allowed TOC manipulations. (This feature was removed in later EAC versions.)

 

SHM-CD - Is actually: Super HIGH Material Compact Disc....(not HARD)

(Super High Material CD) is a superior quality CD fully compatible with all CD players. SHM-CD utilises a higher optical grade polycarbonate material originally developed for LCD screens, and the enhanced transparency of the SHM-CD results in more clarity, depth and definition of sound, bringing the listener ever closer to the music of the original master.....(apparently)

 

Why would the SACD layer of an SACD necessarily have a different mastering than the CD layer?

 

I recall some DG SACDs that didn’t. I don’t own any. I do have a 4+ hour two channel SACD (possible because it is single-layer and has no surround content).

 

Thank you. Someone else mentioned that so I posted an update but it’s impossible to update the original so I will forever hang my head in shame. See above for details. I will never live this down

 

OP: I believe SHM-CD stands for Super High Material not Super Hard.
You may be confusing it with a porn flick.

 

Sorry Christian, missed your quote.
I use that prebeta for SUBQ pre-emphasis detection, no go-doesn't even detect the disc.
"No audio CD in drive"

 

Not on this forum, but: Compact disc - Wikipedia

I'm not sure what you are trying to achieve here. The Red Book refers to the color of the specification book, but the format itself is Compact Disc-Digital Audio (CD-DA, but commonly just CD). All the following named 'formats' (except for SACD) are merely special cases of CD-DA!

The different metals have slightly different reflectivity at the laser wavelengths used (as I recall, silver is the best for CD), which can affect the level of the signal at the photodetector of the laser pick-up. Also, I'm pretty sure the 'grain size' is different, so metals like gold can more accurately coat the information layer during the sputtering process. Forum member @ffracer may have more info on this topic.

So, use of gold (or other metals) can produce CDs that MEASURE better/differently to standard CDs. However, since standard CDs work, there is no indication that gold (or other CDs) will sound any better.

Do readers know what you mean by layers A, B and C?

Unfortunately, some in the audio press have tried to suggest that there are all kinds of tweaky, analog-like phenomena in CD. It's nonsense, of course, but that hasn't stopped manufacturers (mostly in Japan) from playing to these fears with high-priced 'improved' products. It is true that you can use more optically pure polycarbonates or other materials like cyclo-olefin to make the discs, and they may well measure better than standard polycarbonate CDs. However, this is a solution to a problem that does not exist. CD works! If you were making some special archival disc (for very long term storage or launching to a remote galaxy) you may want to use the most optically pure materials with gold or platinum to prevent oxidation, etc., but you don't need any of these things for a standard CD.

It should be pointed out that sputtering using gold or platinum targets is much more expensive than using aluminum because so few clients want it.

The theory behind using a blue laser in glass mastering is that it can produce a much smaller feature size, hence it can more accurately delineate the pits/lands. This may well be true, and, again, may well result in a disc that measures differently/better in some/all parameters than a bog-standard CD. However, as stated above, CD works. You can prove that your CD mechanism extracts the data perfectly from the disc. So, what is there to improve?

I have no idea what you mean by 'aims to reduce error correction which is an intellectual exercise at this point as it doesn’t make any difference to sound quality due to built in error correction mentioned before'. The CIRC encoder/decoder design is specified for CD, and disc manufacturers have to make discs which conform to a ton of parameters. However, the one thing they do not have to do is make error-free discs! A pressed CD is considered within spec if it has less than 220 bit errors per SECOND. The discs we buy typically have less than 10, and I have seen CD-R measurements that approach zero.

A case could be made that use of exotic materials could result in a higher margin for disc damage, since you started with fewer errors. However, I've not seen this case being made for SHM, XRCD, etc.

So, all the above fall under CD-DA, since only the materials used, or manufacturing processes, have changed. The same is true for discs which use noise-shaping like Sony's Super Bit Mapping (which is probably all of them these days but the method used is not explicitly stated on the CD booklet). SBM, and its rivals, were psychoacoustic-based improvements to CD playback that were still 100% compatible with all CD players.

In contrast, HDCD required an additional decoder, and it was unfortunate that Warner Bros. used it so extensively since the major chip/player manufacturers were never going to adopt it (not invented here syndrome). Fortunately, software decoding now allows us to get around this limitation.

I don't know what you mean by software as SACD is not compatible with computer drives! You need an SACD player of some form, even if you have the necessary PS3 or Blu-Ray player which enables ripping and subsequent file playback.

As for the royalty situation, I don't know why Sony keeps getting mentioned in isolation, but the ace that Philips and Sony played with regard to SACD was that they granted SACD license rights to all existing CD license holders:

Sony Global - Press Release - Philips, Sony Announce Licensing Plans for DSD, Super Audio CD

"Licensees of the current CD format would have the option of expanding their agreements to include the Super Audio CD under the same royalty structure used for the audio CD"

That was something DVD-A could not compete against, since all the key players already had a CD license!

The Scarlet Book gives the artistic community the freedom to do what they want. Hybrid SACDs have been produced with:

1. completely different program in the CD and SACD layers;
2. different masterings of the same program in the CD and SACD layers (e.g., SH has explained that he did this for the AF SACDs)
3. the SACD mastering rendered to CD quality, usually using something like Sony's SBM-Direct processing

In case 3, the only thing that would account for any difference in sound quality would be the higher resolution of SACD.

 

Doing some more research on what that two disc De/Vision comp uses CC wise, looks like it has a 'data' section on the outer side of the disc. Think I need a ripper that rebuilds the table of contents. I tried cue-tools/ripper with no luck.

 

I have a couple of those, Moody Blues' Days of Future Passed and Santana's Abraxas.

I also have at least a couple of CDs that feature Dolby Surround, but are compatible with stereo playback, Victory at Sea V.1 (1959 rerecording) and Voices of Ascension From Chant to Renaissance.

... and a few DualDiscs.

 

Somehow I seem to have missed this thread. I would add Rock Ridge format, even though it was for data on UNIX systems. Supposedly universal in that context, it still played hell with some versions of UNIX. No reason it couldn't contain audio.

 

I know this is late, but you can rip HDCDs and decode them. I use dBpoweramp, and with it, while you're ripping CDs you can select the "HDCD" DSP and it will decode the HDCD and save the output as 24/44.1 files. It makes the one HDCD I have, Green Day's Nimrod, sound fantastic with the peak extend it has

 

Oh and there's even a Mac version!
NOW this makes me wonder what the heck gets streamed from Apple Music etc-are those titles correct? Or does someone carelessly upload the HDCD encoded master...

 

Yeah, like the clipped CD layer of Dark Side Of The Moon, what idiocy. SACD was interesting, too bad Sony bungled it so much. Did Philips ever even do much with it? I don't recall much from them- a couple players, I don't even remember if any SACD releases.

 

That's the same program in both layers, just different masterings. There are SACDs with completely different music in the different layers/zones.

Philips solved some of the key technical challenges like the hybrid disc and DSD lossless encoding. At the time of SACD's launch, Philips still owned Marantz, so most SACD products carried the Marantz name. Unfortunately, just before SACD was launched, then relatively new CEO Cor Boonstra, faced with conflict between PolyGram and the CD-R division of Philips Consumer Electronics, opted to sell PolyGram to Seagram for nearly 11 billion dollars (I'm not sure any of the remaining majors would be worth a fraction of that today).

Seagram buys PolyGram from Philips for $10.6bn