Disks Played with Laser Beams

Topic: Disks Played with Laser Beams (Read 664 times) previous topic - next topic

0 Members and 1 Guest are viewing this topic.

Disks Played with Laser Beams

2020-08-14 00:33:37

I've seen this in the past, a little, but why haven't record players that operate on laser beams directed at the grooves become fantastically popular?

This way the record *never* wears out, and surely by 2020 the technology exists to make a *perfect* reproduction of the information the grooves contain. And any dust is much easier to electronically remove since a needle doesn't actually have to touch the dust and make a noise.

Re: Disks Played with Laser Beams

Reply #1 – 2020-08-14 02:34:06

https://en.wikipedia.org/wiki/Laser_turntable

They exist but are complex and don't work that well.

Re: Disks Played with Laser Beams

Reply #2 – 2020-08-14 03:00:32

The record itself was always weak link (with a good turntable & cartridge) so a better playback system doesn't help that much. If they were able to get good sound out of it, it would have been nice to avoid record wear.

From the Wikipedia article, it appears that it's difficult to get a good signal-to-noise ratio optically. Probably because it was designed for mechanical playback. Film used to have optical sound but it wasn't perfect either (until it went digital).

The first Laserdiscs were analog but I don't know what the quality was like. Probably not that great since they later went digital.

Re: Disks Played with Laser Beams

Reply #3 – 2020-08-14 09:54:40

Quote

fantastically popular?

$20.000 (later $10.000) for a laser turntable by ELP might give you a clue

Re: Disks Played with Laser Beams

Reply #4 – 2020-08-14 17:58:10

Quote from: DVDdoug on 2020-08-14 03:00:32

The record itself was always weak link (with a good turntable & cartridge) so a better playback system doesn't help that much. If they were able to get good sound out of it, it would have been nice to avoid record wear.

From the Wikipedia article, it appears that it's difficult to get a good signal-to-noise ratio optically. Probably because it was designed for mechanical playback. Film used to have optical sound but it wasn't perfect either (until it went digital).

The first Laserdiscs were analog but I don't know what the quality was like. Probably not that great since they later went digital.
/quote]

Laserdisc analog audio was AFM and was similar in quality to Beta HiFi or VHS HiFi. The video was always FM, almost the same spectrum as PAL 1" SMPTE C video tape (even for NTSC discs).
When Laser went digital it added 2 PCM channels and kept the AFM channels.

G²

Re: Disks Played with Laser Beams

Reply #5 – 2020-08-14 19:22:03

Quote

$20.000 (later $10.000) for a laser turntable by ELP might give you a clue

And the Wikipedia article says they don't sound that good (noisy).

If there was enough demand to make millions of them in China with child-slave labor the price could probably come down.

It amazes me that I can buy a Blu-Ray player for less than $50. But "audiophiles" who buy this sort of thing LIKE high prices!

Whenever I see something like this, or any "improvements" with "records" my 1st thought is, Now, if they could make them digital and make the discs smaller...

Re: Disks Played with Laser Beams

Reply #6 – 2020-08-15 00:01:02

The biggest problem with the ELP laser turntable was that the tiniest piece of dust got read and interpreted as signal by the laser. So it was important to scrupulously clean the LPs.
In contrast, a mechanical stylus tends to plough through minor dust and brush it aside.

Re: Disks Played with Laser Beams

Reply #7 – 2020-08-15 07:28:52

Quote from: cliveb on 2020-08-15 00:01:02

The biggest problem with the ELP laser turntable was that the tiniest piece of dust got read and interpreted as signal by the lase

I think the problem is more conceptual as DVDDoug alluded to above. The whole basis for vinyl playback is the physical interaction of the stylus and the grooves of the record and the resulting vibration.

That physical interaction is substantially eliminated with laser playback and from what I've heard the results are really poor. I have some CDs with vinyl rips taken using laser capture where this is marketed as a feature, but the sound is dull and lifeless. Very disappointing.