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One theory I saw argued the punch card size was the reason for 80x24. But why were punch cards that size? They were designed off of the cards used for the cens

One theory I saw argued the punch card size was the reason for 80x24. But why were punch cards that size? They were designed off of the cards used for the census. Why were the census cards that size? Because they were modeled after the dollar bill size. I do love thought experiments like this but do believe they’re insatiably unresolvable.

ronsor 7mo ago
In the end, all reasons resolve to either "it's what we had at the time" or "someone thought it looked good."
- theamk 7mo ago
  Not always, for example original CD disks had capacity of 74 minutes to accommodate Beethoven's Ninth Symphony.
  - rasz 7mo ago
    That one also turned out a myth :) CD size was determined by Cassette tape dimensions (diagonal, human can still hold one in one hand) and that combined with conservative pits/lands/track pitch choice drove the play time. thus CD runtime was derived from something "what we had at the time".
    - antiterra 7mo ago
      The story as told may be inaccurate but it wasn’t simply ‘what we had at the time’ either. The 74 minute length resulted from Sony rejecting the Philips 60 minute 11.5cm diameter “Pinkeltje” disc size in favor of a 12cm diameter. It’s quite possible that Sony’s Norio Ohga simply argued that the 9th symphony or various operas fitting would be enough of an advantage for the slight size increase without meaningfully decreasing portability.
      - rzzzt 7mo ago
        Meanwhile the LP crowd was flipping sides like it was Ultima VIII (slight exaggeration). Why would it be critical for a new format to do away with multi-disc releases if the customer base has already grown accustomed to them?
        rbanffy 7mo ago
        Because it was annoying to flip the disk in the middle of the thing.
        ndiddy 7mo ago
        For classical music it's a problem because the long track lengths mean that you'll have to flip the record over in the middle of a piece. This was enough of an annoyance that one French label in the 70s created special records just for classical music with extra tightly packed grooves that could hold close to an hour on each side (https://www.discogs.com/label/184887-Trimicron https://www.discogs.com/label/184887-Trimicron). The downside of this is that the maximum recording volume is significantly reduced so there's a lot more background noise than on a normal record.
    - theamk 7mo ago
      You got any source for this? The symphony story might be a legend, but it's pretty well known that the original design was somewhere in 10-11cm range, but this was eventually increased to 12 cm. The "diagonal cassette size" seems extremely far-fetched - first, who cares about this? If you are worried about boxes, shelves etc.. you want horizontal size, which 10 cm. And you are worried about holding in hand, 12cm is not very convenient for the smaller hands, a smaller size would be better.
      - rbanffy 7mo ago
        When respectfully handling them out of the box, I always stuck my index finger in the central hole and the thumb on the border. I have large hands but I rarely held them by the borders.
      - tracker1 7mo ago
        If anything, I'd have guessed that the size of an 8-track in a car stereo was probably a larger influence on potential form factors for CD audio. Since car stereos were at least somewhat normalized in the early 80's. Not speaking to an adapter, just in terms of what would "fit" in a typical stereo hole in a car. That said, I doubt that's the reality either... it's probably a number of factors. I am slightly surprised that a USB based read-only media format standard for players hasn't materialized, though it seems that online/rental models are what the industry really wants.
      - rasz 7mo ago
        Source is Dr. Kees A. Schouhamer Immink. Philips’ principal engineer in the joint efforts of Sony and Philips to develop the Compact Disc (CD) https://www.turing-machines.com/pdf/cdstory.htm https://www.turing-machines.com/pdf/cdstory.htm: >The disk diameter is a very basic parameter, because it relates to playing time. All parameters then have to be traded off to optimise playing time and reliability. The decision was made by the top brass of Philips. 'Compact Cassette was a great success', they said, 'we don't think CD should be much larger'. >As it was, we made CD 0.5 cm larger yielding 12 cm. (There were all sorts of stories about it having something to do with the length of Beethoven's 9th Symphony and so on, but you should not believe them.) > The 8-14 bit channel code was agreed and all the specifications between them led to a playing time of 75 minutes.
- rzzzt 7mo ago
  "Everybody just liked it that way and it costs too much to change it now": https://www.exocomics.com/743/ https://www.exocomics.com/743/
staplung 7mo ago
And the reason they were modeled after the dollar bill size is because there were already many types of systems for storing and organizing them. That came in handy for the census. The old BBC Connections series has a segment with James Burke using the old census tabulators. https://www.youtube.com/watch?v=z6yL0_sDnX0&t=2640s https://www.youtube.com/watch?v=z6yL0_sDnX0&t=2640s
rbanffy 7mo ago
> But why were punch cards that size? Something related to the width of a two-horse Roman carriage… Not sure ;-)

ronsor 7mo ago

In the end, all reasons resolve to either "it's what we had at the time" or "someone thought it looked good."

theamk 7mo ago
Not always, for example original CD disks had capacity of 74 minutes to accommodate Beethoven's Ninth Symphony.
- rasz 7mo ago
  That one also turned out a myth :) CD size was determined by Cassette tape dimensions (diagonal, human can still hold one in one hand) and that combined with conservative pits/lands/track pitch choice drove the play time. thus CD runtime was derived from something "what we had at the time".
  - antiterra 7mo ago
    The story as told may be inaccurate but it wasn’t simply ‘what we had at the time’ either. The 74 minute length resulted from Sony rejecting the Philips 60 minute 11.5cm diameter “Pinkeltje” disc size in favor of a 12cm diameter. It’s quite possible that Sony’s Norio Ohga simply argued that the 9th symphony or various operas fitting would be enough of an advantage for the slight size increase without meaningfully decreasing portability.
    - rzzzt 7mo ago
      Meanwhile the LP crowd was flipping sides like it was Ultima VIII (slight exaggeration). Why would it be critical for a new format to do away with multi-disc releases if the customer base has already grown accustomed to them?
      - rbanffy 7mo ago
        Because it was annoying to flip the disk in the middle of the thing.
      - ndiddy 7mo ago
        For classical music it's a problem because the long track lengths mean that you'll have to flip the record over in the middle of a piece. This was enough of an annoyance that one French label in the 70s created special records just for classical music with extra tightly packed grooves that could hold close to an hour on each side (https://www.discogs.com/label/184887-Trimicron https://www.discogs.com/label/184887-Trimicron). The downside of this is that the maximum recording volume is significantly reduced so there's a lot more background noise than on a normal record.
  - theamk 7mo ago
    You got any source for this? The symphony story might be a legend, but it's pretty well known that the original design was somewhere in 10-11cm range, but this was eventually increased to 12 cm. The "diagonal cassette size" seems extremely far-fetched - first, who cares about this? If you are worried about boxes, shelves etc.. you want horizontal size, which 10 cm. And you are worried about holding in hand, 12cm is not very convenient for the smaller hands, a smaller size would be better.
    - rbanffy 7mo ago
      When respectfully handling them out of the box, I always stuck my index finger in the central hole and the thumb on the border. I have large hands but I rarely held them by the borders.
    - tracker1 7mo ago
      If anything, I'd have guessed that the size of an 8-track in a car stereo was probably a larger influence on potential form factors for CD audio. Since car stereos were at least somewhat normalized in the early 80's. Not speaking to an adapter, just in terms of what would "fit" in a typical stereo hole in a car. That said, I doubt that's the reality either... it's probably a number of factors. I am slightly surprised that a USB based read-only media format standard for players hasn't materialized, though it seems that online/rental models are what the industry really wants.
    - rasz 7mo ago
      Source is Dr. Kees A. Schouhamer Immink. Philips’ principal engineer in the joint efforts of Sony and Philips to develop the Compact Disc (CD) https://www.turing-machines.com/pdf/cdstory.htm https://www.turing-machines.com/pdf/cdstory.htm: >The disk diameter is a very basic parameter, because it relates to playing time. All parameters then have to be traded off to optimise playing time and reliability. The decision was made by the top brass of Philips. 'Compact Cassette was a great success', they said, 'we don't think CD should be much larger'. >As it was, we made CD 0.5 cm larger yielding 12 cm. (There were all sorts of stories about it having something to do with the length of Beethoven's 9th Symphony and so on, but you should not believe them.) > The 8-14 bit channel code was agreed and all the specifications between them led to a playing time of 75 minutes.
rzzzt 7mo ago
"Everybody just liked it that way and it costs too much to change it now": https://www.exocomics.com/743/ https://www.exocomics.com/743/

staplung 7mo ago

And the reason they were modeled after the dollar bill size is because there were already many types of systems for storing and organizing them. That came in handy for the census. The old BBC Connections series has a segment with James Burke using the old census tabulators. https://www.youtube.com/watch?v=z6yL0_sDnX0&t=2640s https://www.youtube.com/watch?v=z6yL0_sDnX0&t=2640s

rbanffy 7mo ago

> But why were punch cards that size? Something related to the width of a two-horse Roman carriage… Not sure ;-)