Re: pseudo-YASID: Spang on, but no cigar

Christian Weisgerber  <naddy@mips.inka.de> wrote:

On 2024-12-24, Joy Beeson <jbeeson@invalid.net.invalid> wrote:
>

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


--
"C'est un Nagra. C'est suisse, et tres, tres precis."