pseudo-YASID: Spang on, but no cigar

[Joy Beeson]

In a story I wrote on a typewriter, I predicted that everyone in my
far-future setting would carry a pocket terminal.

I also said that a terminal that included a sound system would be
twice as bulky as everyone else's. (The length of sound waves
controls the sizes of microphones and speakers, so they can't be
tiny.)


Are there published stories in which predictions are laughably
correct?

[Robert Woodward]

Post by Joy Beeson
In a story I wrote on a typewriter, I predicted that everyone in my
far-future setting would carry a pocket terminal.
I also said that a terminal that included a sound system would be
twice as bulky as everyone else's. (The length of sound waves
controls the sizes of microphones and speakers, so they can't be
tiny.)
Are there published stories in which predictions are laughably
correct?

Don't you mean laughably INcorrect? After all, every cellphone has a
microphone and speaker and it is the size of the video screen that
determines the size of smartphones.

[Christian Weisgerber]

Post by Joy Beeson
I also said that a terminal that included a sound system would be
twice as bulky as everyone else's. (The length of sound waves
controls the sizes of microphones and speakers, so they can't be
tiny.)

Tell us more. The traditional frequency band for transmission of
human voice is 300 to 3,400 Hz, which in air corresponds to wavelengths
of about 0.1 to 1.1 meters.

[Scott Dorsey]

Post by Christian Weisgerber

Post by Joy Beeson
I also said that a terminal that included a sound system would be
twice as bulky as everyone else's. (The length of sound waves
controls the sizes of microphones and speakers, so they can't be
tiny.)

Tell us more. The traditional frequency band for transmission of
human voice is 300 to 3,400 Hz, which in air corresponds to wavelengths
of about 0.1 to 1.1 meters.

This sets the limit of an efficient voice-grade speaker in free air to
about the size of a transistor radio. If you want to make it smaller,
you either need to stop working in free air (like using earplugs) or use
long folded tubes and sacrifice a lot of efficiency (which is what cellphone
speakers do.)

You can draw a triangle with regard to speakers: each apex marked
SIZE, LF EXTENSION, and EFFICIENCY. You can be anywhere inside the
triangle but you can't get out of it.
--scott