CD vs SACD in STEREO

Someone said that redbooks are not 24 bit . I have a lot of them. SACD is one bit. Same guy says SACD was always about 5.1 surround. The original single layer ones from 1999 on mostly blue colored discs only play on dedicated SACD players and none were surround only 2 channel stereo like music has always been. The multi channel discs came in when they started to produce hybrid with 2 layers , top one is redbook and imbedded layer is SACD.

@yoyoyaya 

The state of computer technology at the time would not have made it feasible to mix it digitally, and it wasn't recorded to hard disc in the first place anyway

The computer technology was there, but the cost would have been prohibitively high if the mixing had to be computed in real time!

My understanding is that Brothers in Arms was recorded direct to a 24-track Sony digital tape recorder.  Being digital, it really does not matter what the medium is.  The first 'mainframe' I programmed had direct access storage devices (to use IBM's name for disks) which were actually based on 2-m continuous loops of 2" wide magnetic tape blown round by compressed air.

The record scandal was the other way round - disks were marketed as all-analogue but used digital files!

Anyway, happy new year

@zx10 

Someone said that redbooks are not 24 bit . I have a lot of them. SACD is one bit. Same guy says SACD was always about 5.1 surround. The original single layer ones from 1999 on mostly blue colored discs only play on dedicated SACD players and none were surround only 2 channel stereo like music has always been. The multi channel discs came in when they started to produce hybrid with 2 layers , top one is redbook and imbedded layer is SACD.

That would have been me.  I did not quote this earlier, but ChatGPT is absolutely right on this one:

A "24-bit Red Book CD" is a contradiction because Red Book CD (Standard CD) is strictly defined as 16-bit audio at a 44.1 kHz sample rate, offering about 96dB dynamic range, while 24-bit audio is a higher-resolution format (like Hi-Res Audio) with significantly more dynamic range (up to 144dB), used in streaming or downloads, not standard CDs. You can’t natively burn 24-bit files to a standard CD; they must be converted down to 16-bit/44.1kHz for playback on CD players, although professionals use 24-bit for better mixing headroom before creating the final 16-bit master

SACD is similarly defined by Philip’s Scarlet Book available under licence. 

ChatGPT says:

Key aspects of the Scarlet Book and multichannel audio:

• High-Resolution Audio: SACD is a high-resolution format, primarily using Direct Stream Digital (DSD) technology, offering superior dynamic range and frequency response compared to standard CDs.
• Multichannel Support: The format was designed to support both high-quality stereo and multichannel surround sound (e.g., 5.1 surround). Multichannel SACDs provide a more immersive listening experience with discrete back and center channels.
• Mandatory Stereo Layer: While early SACDs could be multichannel-only, revisions to the Scarlet Book in March 2004 made the inclusion of a 2-channel stereo content layer mandatory on every released SACD.

So SACD was always multi-channel from the get-go, the two-channel inclusion was mandated 5 years later.

Like Compact Discs, the format was designed around classical music, not pop/rock.  Classical music dominates SACD production.  North America in this regard is an outlier compared with Europe and Japan.

@richardbrand @big_greg is right.. The first SACD's were 2-channel only. They only had a left and right analog out and usually one digital out for pcm on cd playback. And the first discs were only two channel. Only DVD-A was multi channel for a very long time after that. I sold them both in '99.

Alot of the dac chips have 8 channels in them and it's nice. I do like akm and ess pro as I have numerous generations over the years.even burrows some older ones have 8 chips in them . Enjoy the digital to analog phase.