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How CD pregaps gained their hidden track superpowers

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Re: How CD pregaps gained their hidden track superpowers

#61

Post by ssl-3 »

kevin_thibedeau wrote: post #42
ssl-3 wrote: post #37

Earlier quoted context omitted.

That's probably the best way to do it, given common toolsets and players. I also rip pregaps as lead-outs (rather than the lead-ins that the structure may appear to suggest). It's things like this that make me wish that we'd landed on on a good, popular way to store albums (with metadata!) instead of individual tracks -- or to at least reassemble individual tracks' files properly into whole albums without glitches an…

In addition to lossy compressed track files I also generate a FLAC with embedded cue as a master copy of the original. It's useful for recreating the whole recording for mass editing. I have a few discs mastered with preemphasis that needed correction. I too hope there will be a day when all FLAC players support track navigation. The reality is the music album has had its day in the sun and will largely be a forgotte…

You're not wrong. New music isn't frequently recorded with the intent for it to be heard in an album-oriented way.

But the albums I like to listen to as albums will remain cohesive albums for an eternity.

Lots of stuff from Roger Waters is cohesive in that way, which is perhaps something a person might expect me to say.

But also lots of stuff from Maynard James Keenan, Trent Reznor, and even Marilyn Manson is also this way, which is perhaps less expected.

(And sure, I can rip an album as an album and convert that to a singular MP3 that I can play as an album almost anywhere, and it needs to be a single file since MP3s can't be perfectly concatenated. But then, I can't easily skip around on that singular album when it behooves me to do so.

I could do both things when it was still in CD format.)

Re: How CD pregaps gained their hidden track superpowers

#62

Post by ssl-3 »

qingcharles wrote: post #60
ssl-3 wrote: post #37

Earlier quoted context omitted.

That's probably the best way to do it, given common toolsets and players. I also rip pregaps as lead-outs (rather than the lead-ins that the structure may appear to suggest). It's things like this that make me wish that we'd landed on on a good, popular way to store albums (with metadata!) instead of individual tracks -- or to at least reassemble individual tracks' files properly into whole albums without glitches an…

I'd love a new solution that wasn't "break the CD data into pieces." I've never looked inside a CUE file, but it's just text and I don't think it supports meta data, right? We need like a new CUE file to go with the FLAC, right? p.s. https://news.ycombinator.com/item?id=40923646

Ideally, I think I'd want a singular container (of whatever sort) that has the album's audio, the music-related timing metadata (as applicable), and whatever other metadata may be appropriate (lyrics? liner note graphics? music videos? sure!).

The audio should be able to be FLAC. But it should also be able to be anything else, like Vorbis or MP3 or AAC or IDK. It needs to be able to be played continuously without aberration (which can't actually be done with a group of MP3 streams).

The audio needs to be able to be seekable, like a CD is also seekable. By track. By index. (With pregaps, where appropriate -- because CDs also have pregaps.)

Other potential metadata must be able to include whatever subcodes are involved in things like CD+G[0] and HDCD and CD Text, since all of those are supersets of the regular datastream and playback is compatible with any CD player.

And it needs to be a singular container file because...well, that's just easier to keep track of as the years go by and data migrates.

Only then, will we have the beginning of a valid archive format for audio CDs as they actually still exist on [some] store shelves today.

(Some stuff can be optional, just as lots of things are optional inside of an MKV container for a film.)

[0]: Almost nobody ever used this outside of the 1990s karaoke world, but Information Society's self-titled album includes an illustrated sequence, with lyrics, that is completely implemented in CD+G and that runs for the entire length of the album. And I should be able to render that locally here in 2024 from a container on my pocket supercomputer instead of watching a bad rip from a Sega Genesis: https://www.youtube.com/watch?v=b89sSa8QlLg

Re: How CD pregaps gained their hidden track superpowers

#63

Post by kevin_thibedeau »

qingcharles wrote: post #60
ssl-3 wrote: post #37

Earlier quoted context omitted.

That's probably the best way to do it, given common toolsets and players. I also rip pregaps as lead-outs (rather than the lead-ins that the structure may appear to suggest). It's things like this that make me wish that we'd landed on on a good, popular way to store albums (with metadata!) instead of individual tracks -- or to at least reassemble individual tracks' files properly into whole albums without glitches an…

I'd love a new solution that wasn't "break the CD data into pieces." I've never looked inside a CUE file, but it's just text and I don't think it supports meta data, right? We need like a new CUE file to go with the FLAC, right? p.s. https://news.ycombinator.com/item?id=40923646

Cue is a bodge that should never have become a defacto standard. Joerg Schilling's cdrdao tool has its own TOC format that faithfully captures everything including index marks, various flags, and multilingual CD text but it was ignored by everything else in the heyday of the ripping era. Nowadays we'd be better off with a standard yaml/json format that duplicates what cdrdao provides.

Re: How CD pregaps gained their hidden track superpowers

#64

Post by ssl-3 »

pseudosavant wrote: post #59
ssl-3 wrote: post #29

One less-secretive way I've seen pregaps used is for live recordings. The crowd noise betwixt songs can be contained in a pregap, so that it is only ever heard when listening to the album straight-through (instead of in shuffle or track-program mode). --- Another fun feature of audio CDs is indexes. A disc can have 99 tracks, and each track can have some pregap (including track 1, as the article discusses). And each…

I mastered a CD in 2000 for a band that wanted a secret track at the end. I came up with a novel way to do it. There were a dozen regular tracks. A bunch of empty ones. And the final track over about a dozen tracks of varying length with no gap. Used all 99 tracks. I could only pull it off with this CD burning software that didn’t have a UI. It took a text file as input at the command line. But it could do everything…

I've had visions of putting a CD together that was that way, but with pregaps and indexes utilized as well.

"WTF? The time counter keeps going forward, and then sometimes it goes backwards! And using the track seek buttons completely eliminates some parts that I can hear if I don't touch anything!

It's a whole different song entirely when you program tracks 39, 40, and 52 in a loop, and IDFK what it is with this Index number that only always showed "1" before.

Oh wait. Srsly? From tracks 71-93, it's using the index to count beats...and the track number to count measures? No, that can't be it. Except...."

Re: How CD pregaps gained their hidden track superpowers

#65

Post by chaboud »

pseudosavant wrote: post #59
ssl-3 wrote: post #29

One less-secretive way I've seen pregaps used is for live recordings. The crowd noise betwixt songs can be contained in a pregap, so that it is only ever heard when listening to the album straight-through (instead of in shuffle or track-program mode). --- Another fun feature of audio CDs is indexes. A disc can have 99 tracks, and each track can have some pregap (including track 1, as the article discusses). And each…

I mastered a CD in 2000 for a band that wanted a secret track at the end. I came up with a novel way to do it. There were a dozen regular tracks. A bunch of empty ones. And the final track over about a dozen tracks of varying length with no gap. Used all 99 tracks. I could only pull it off with this CD burning software that didn’t have a UI. It took a text file as input at the command line. But it could do everything…

The Nine Inch Nails “Broken” EP had a couple of tracks at the end of 99, though the middle tracks were all 1-second blanks.

Re: How CD pregaps gained their hidden track superpowers

#66

Post by eyelidlessness »

egypturnash wrote: post #46
cainxinth wrote: post #31

Earlier quoted context omitted.

> Broken was re-released as one CD in October 1992, having the bonus songs heard on tracks 98 and 99 respectively, without any visual notice except for the credits, and tracks 7–97 each containing one second of silence. https://en.wikipedia.org/wiki/Broken_(Nine_Inch_Nails_EP)#Pa... Amarok (1990) by Mike Oldfield is a single hourlong track with 53 index marks. https://en.wikipedia.org/wiki/Amarok_(Mike_Oldfield_album…

Broken was absolutely perfect to put into a multi-disc player along with TMBG's Apollo 18 , which contains "Fingertips", a suite of 21 very short songs. Set it to shuffle songs from everything in the player, and enjoy your sonic whiplash

If you want sonic whiplash without so much effort, you can also listen to a Fantomas album in its original order.

Re: How CD pregaps gained their hidden track superpowers

#67

Post by qingcharles »

sho wrote: post #49
d332 wrote: post #36

Earlier quoted context omitted.

But that's not my goal. I'd like to be able to observe every grove, the physical encoding of data, and see if I could implement decoding from scratch. First problem is though that I don't know how to get a microscopic image of the disc.

this seems responsive: https://superuser.com/questions/140874/is-it-technically-pos...

I wonder if you could just tear the controller out of a CD/DVD drive and build a new one from scratch, kind of like the new floppy controllers being used now to read the raw magnetic data. You could just command the head to move to the center, find the beginning of the data and just keep reading until you hit the buffers.

Re: How CD pregaps gained their hidden track superpowers

#68

Post by LeoPanthera »

Semi-related: "Minidisc" is an album by Gescom (who are really Autechre in disguise) released, as the name suggests, only on Minidisc, containing 88 tracks which are designed to be played on shuffle, because Minidisc, unlike CD or any other physical format, can be shuffled with no audible gap between tracks.

Each track is designed to segue into any other so the album is different every time you play it.

Re: How CD pregaps gained their hidden track superpowers

#70

Post by ssl-3 »

qingcharles wrote: post #67
sho wrote: post #49

Earlier quoted context omitted.

this seems responsive: https://superuser.com/questions/140874/is-it-technically-pos...

I wonder if you could just tear the controller out of a CD/DVD drive and build a new one from scratch, kind of like the new floppy controllers being used now to read the raw magnetic data. You could just command the head to move to the center, find the beginning of the data and just keep reading until you hit the buffers.

Sorta, kinda? It's a bit of a different game.

Floppies (most of them, anyway) have fixed track widths, and these tracks are arranged cylindrically, and these cylinders align with the steps of the stepper motor that is used to actuate the head assembly.

It's relatively easy, with the right ratio betwixt step advancement and track width, to get the head moving properly on a new implementation of a floppy controller. Want to read track 1? Step to the head N times to reach track 1 from wherever it started, and read it. Next, want to read track 33? Step the head N times to track 33, and read that.

But tracking the spiral groove of a CD is a very different problem to solve. Steps tend to lose their meaning. Instead of electromagnetic steps, it involves 3 different laser beams: Two to continuously keep the head centered where it needs to be on the ever-changing groove using a servo feedback loop, and a third to read the data from the pits and lands from the middle of that groove.

Is it do-able? Sure! People with far less advanced tech than we on HN might have laying around did it 40+ years ago.

It's just a very different nut to crack than reading a floppy is, even if the mechanical and optical bits are recycled.

(And that's just head positioning. The pits and lands still needs to be read, and those reflect back from the disc as optical phase shifts, not as changes in magnetic polarity and/or amplitude.)

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