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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

#112
post #81

I read this whole thing twice and I now know what pregaps are and the history but still have no idea why people would put them on a CD or why they’re useful for hidden tracks.

The writing is not good; I gave up part way through. It's weirdly elliptic and almost autistic in its focus on details and an almost complete absence of a big picture. It could do with some kind of proper context-setting introduction, at the very least.

A CD audio frame is defined as exactly 1/75th of a second (588 samples per channel). I don't know why the article waffles around with these poor wordings (emphasis mine):

> These albums all had a pregap of either 32 or 33 “frames,” with a frame representing a length of about 1/75th of a second, per Hydrogen Audio’s Wiki.

> To offer a small correction to the original question now that we know we’re talking about 74 frames per second rather than 60 or 100

It's needlessly confusing and undermines my confidence of the entire article.

Re: How CD pregaps gained their hidden track superpowers

#113

Earlier quoted context omitted.

Yes, there's been a serious issue recently reported. Apparently, it has triggered bureaucrats on the internet who can't acknowledge something innocuous that's never caused any problem for decades.

Link?

https://news.ycombinator.com/item?id=40922903

Re: How CD pregaps gained their hidden track superpowers

#114

Earlier quoted context omitted.

How much hidden audio could be stored? Was it limited to something negligible like a couple of seconds? Or could you store a whole five-minute recording in there or something?

There doesn't seem to be a limit, this https://en.wikipedia.org/wiki/List_of_albums_with_tracks_hid... mentions a 27 minute live recording.

I guess the limit is some milliseconds short of 74 minutes.

Re: How CD pregaps gained their hidden track superpowers

#115
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 have an early CD (Bach's Goldberg variations, played by Glenn Gould) which is one track with 31 index markers.

My (early) Philips CD player dealt with it fine, but since then it's been a bit of a problem...

Re: How CD pregaps gained their hidden track superpowers

#116
post #64

Earlier quoted context omitted.

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 Inde…

I thought I'd really (ab)used the CD specs, but don't recall ever trying indexes. Curious how most CD players, which only had a two-digit track indicator, handled indexes. I would have used that if I had known about it.

Re: How CD pregaps gained their hidden track superpowers

#117
post #10

I've been using https://github.com/whipper-team/whipper to digitize CD's, and it supports identifying Hidden Track One Audio (HTOA) when it exists and is not blank. Add in MusicBrainz Picard and Navidrome and you have a really nice solution.

Whipper user here also. If you've not yet encountered it, as it's not as prevalent in repos as Whipper, Cyanrip is always very much worth a look and has come on in leaps and bounds, with recent updates adding (non compliant) .cue sheet support.

Re: How CD pregaps gained their hidden track superpowers

#119

Earlier quoted context omitted.

I had a set of cds that went with an intro to music theory textbook around ~2009. It did also made heavy use of indices in tracks to do exactly the same thing. My car stereo listed each index as a track. I wish I could remember the name of the textbook because I really liked a lot of the baroque music on the CDs and can't remember who they were by or the titles of the songs...

Do you remember if the textbook was orange (possibly with a two-tone cover design)? I had a really good textbook in college that had a... 4? CD set (with the big jewel case) that had a bunch of tracks and like you I really enjoyed it.

It was a reddish (could be orange, could have been maroon) color lightly mottled in black with a picture of a violin (or cello, idk) set in the lower 2/3 of the cover. I'm somewhat certain it had 6 cds because it filled my disc changer in my stereo, although that detail is fuzzy too.

Re: How CD pregaps gained their hidden track superpowers

#120

Earlier quoted context omitted.

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.

There wasn't really much effort involved. Pick a few discs off the CD rack that I thought will clash interestingly, load up the cd tray of the cheap all-in-one turntable/tape deck/radio/cd unit I had in my room, hit the 'shuffle' button until it tells me it's gonna shuffle everything together, hit play.

Looking Fantomas up on Wikipedia makes it sound like they'd go pretty well with "twenty tracks that sound like the choruses of twenty different songs" and "ninety-something 1s blank tracks plus a few industrial songs", though.

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