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CAV any CLV?
It has something to do with the speed of outer and inner grooves on lap and data

Constant Angular Velocity(CAV) vs Constant Linear Velocity(CLV).

Vinyl is CAV and CD is CLV.

What about tape?

mix4fix wrote:What about tape?

CLV, except for some VERY early units...

Roscoe

Tape is Constant Linear Velocity over the heads.

Because it is reading the information at constant rate (laser reading 1s/0s, reading the tape at a set speed)?

If converting from analog to digital, you think quality of the conversation changes from outer to inner grooves

50 years ago I worked on a Honeywell computer that used a bank of 6 tapedrives. No disks. It would have been similar to these.

https://www.pinterest.co.uk/pin/536772849315564139/

and

https://www.ebay.com/itm/1964-Press-Photo-Vintage-Honeywell-200-Tape-Drive-Computer-1960s-/202671838463

The tape went from the reel down into a vacuum well, up to the tape head, down into another vacuum well and then to the takeup reel. Towards the bottom and top of each well were photocells that either stopped or started the movement of the reels so that the movement of the tape across the read / write heads was CLV and independent of the movement of the reels. They were very reliable.

Back in those days in Australia, it was standard practice to go to the pub each Friday for a boozy lunch. Eventually, I would get back to the office and have to make a decision about my ability to program. My test was to walk into the computer room and look at the row of tape machines while they were performing a sort. If I could work out what was going on by the movement of the reels, I stayed and went to my desk. Otherwise, I just staggered home. However, on Monday I would throw out whatever I had done on Friday afternoon if I had actually managed to produce anything.

ray

ratbagp wrote:50 years ago I worked on a Honeywell computer that used a bank of 6 tapedrives. No disks. It would have been similar to these.

https://www.pinterest.co.uk/pin/536772849315564139/

and

https://www.ebay.com/itm/1964-Press-Photo-Vintage-Honeywell-200-Tape-Drive-Computer-1960s-/202671838463

The tape went from the reel down into a vacuum well, up to the tape head, down into another vacuum well and then to the takeup reel. Towards the bottom and top of each well were photocells that either stopped or started the movement of the reels so that the movement of the tape across the read / write heads was CLV and independent of the movement of the reels. They were very reliable.

Back in those days in Australia, it was standard practice to go to the pub each Friday for a boozy lunch. Eventually, I would get back to the office and have to make a decision about my ability to program. My test was to walk into the computer room and look at the row of tape machines while they were performing a sort. If I could work out what was going on by the movement of the reels, I stayed and went to my desk. Otherwise, I just staggered home. However, on Monday I would throw out whatever I had done on Friday afternoon if I had actually managed to produce anything.

ray

Great story.

Pelliott321 wrote:If converting from analog to digital, you think quality of the conversation changes from outer to inner grooves

The A/D conversion does not change, but the vinyl replay depends on how well the cartridge is tracking outer vs inner grooves.

I prefer minimum phase anti-aliasing filter A/D's for analog inputs like phono for recording.