[Avodah] Explaining boneh/electricity to a non-religious person

[rabbirichwolpoe at gmail.com]

R Zev Sero:
> 1. A computer's *purpose* isn't to make sound.  One is allowed to knock
> on a door, because it is not a sound-making tool; one is not allowed to
> use a door knocker, because it is.

--

IIRC this is a machloqes rishonim
The Rif and X

Some say the g'zeira extends to any "sound maker" such as knocker and
others say ONLY musical instruments - and therefore knockers Are OK -
provided one does NOT use it to tap out a musical beat.
I'm looking @ Orach Hayyim 339:2 and I'm not finding it.

There is a macloqes re: snapping thumbs to quiet a Tinoq...and whether
derech M'shor'rim is applicable

-----------------------

Tangentially
Re:
Klei shir
Microphone
Bicycles

We had a debate offlist

Is microphone a klei sheer - and as such part of the original g'zeira
OR
It's an extension of the original g'zeira - shema yetaqein...?

If included, then extending to a bicycle makes no sense

If an extension, then further extension to apply to bicycle could
indeedmake sense, [albeit one is not compelled to agree to that extesnion]

+++++++++++++++
Tangent
IIRC I asked a sheilah from my late Rosh Yeshiva RSY Weinberg OBM
"what's the issur of microphone on shabbos?"
His answer: "hashmo'as kol"

AIUI then, this would apply to a non-electric megaphone, too

KT
RRW
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