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So I'm archiving a laserdisc, and here's a fun fact about laserdiscs: Some of them have both analog and digital sound tracks! Obviously I'm archiving both of them, but ran into a weird problem: They're out of sync! I'm demonstrating this in an audio editor, by playing them both at once.

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Maybe it's on purpose? The digital signal you have to decode, which takes a moment, and you can buffer it. The analog one you just bang into the amplifier.

I knew about the digital audio track for LaserDisc releases as the main reason why audio archivers actually edit and synced carefully (timing and voices) to the Blu-ray and 4K Ultra HD counterparts (including Dolby Digital AC-3 and DTS 5.1 mixes) to retain the dynamic far field mixes of the media.

Cool! Have you ever seen a Domesday system in action? I once did, working at Broxtowe Further Education College, Nottinghamshire in late 1989. It was hooked up to a BBC Master. The first multimedia system I’d ever seen!

The discs from the Galaxian 3 arcade game have speech on the analog track and music on the digital track. They're routed to different speakers via the outputs on the back of the LD players.

Oh how do they "encode" the analogue signal? I guess it's something like a vinyl record but with light? Does that mean you could dj scratch with them

Nice. I concur with others: The early digital signal is likely to allow for a longer (in time) path for the digital signal to be buffered / decoded / turned back into analog again. It's also easier to delay audio than video, so the large delay is likely just playing it safe.

If you ever want me to take a listen to some audio stuff (and aren't on a time crunch), lmk! In my past life I worked in audio for video games and would enjoy poking at esoteric audio things.

I didn't include a good image with the video, but here's a better one: You can see there's a desync, and that the same audio is on both tracks. You can also see the difference between the analog and digital soundtracks: The analog (top) is way noiser!

0.1s is generally the Max until audio-video offset becomes sup noticeable (lip-sync-error is another term used for this) Somebody must be missing something (that might be you or someone else)

Is there any chance that the digitization process you used for the analogue track might have introduced the lag? I'm not sure how to easily check, though.