[NJARC] Record speeds

[amagoun]

Jim,

Actually Berliner's challenge with earlier patents wasn't form or speed,
but the manner in which he made the grooves.  When he developed disc
recording, Edison and Columbia were selling in a quite different market
for different purposes.  In 1887 neither record format nor speed were a
patent issue; the method of making grooves was.  Instead of engraving or
indenting, Berliner traced vibrations in soot on glass, photoengraved
them, and made a reproduction master by etching the grooves with acid.
He used a disc because mass production was simpler and he traded off
fidelity for loudness.  He cranked his initial records at 30 rpm and
then doubled it to 60.

Through mass production of discs for the new market of home
entertainment that Berliner envisioned, he could sell records for less.
His first commercial records were intended for playback around 70 rpm,
with the stylus's movement activated by the lateral movement of the
groove walls.  Edison and Columbia used vertical, "hill and dale"
recording on cylinders for the sake of playing time, driven by a feed
screw.  The playback stylus was duller than the engraving stylus because
otherwise you'd simply gouge the groove.  The volume was much lower
because the stylus didn't draw on the up and down motion of the groove,
requiring an earphone.  But at that time, Edison nor Columbia were still
pushing phonographs and graphophones for commercial stenography, while
their lessors were beginning to adapt them to jukebox parlors.

As for price, after Victor began cleaning Columbia's clock, it fought
back by doing outrageous things like songs on both sides of the disc for
the same price.

You can read about this at much more length in my dissertation, which
I'm looking forward to revising for publication by the end of the
summer.

cheers,
Alex

Message: 7
Date: Sun, 4 Mar 2007 20:44:58 -0800 (PST)
From: Jim Whartenby <antqradio at sbcglobal.net>
Subject: Re: [NJARC] Record speeds
To: New Jersey Antique Radio Club <njarc at mailman.qth.net>
Message-ID: <212580.20795.qm at web82703.mail.mud.yahoo.com>
Content-Type: text/plain; charset=iso-8859-1

Alex and Nick
It is my impression that Berliner and Johnson got around Edison's
patents by making some obvious changes in method.

Using a disk instead of a cylinder.

Encoding the sound in the record grove sides instead of the grove
bottom.

Changing the speed from 80RPM to 78RPM.

Most important from the consumer point of view, charging less then a
buck for a record!
Regards,
Jim

--
Alexander B. Magoun, Ph.D.
Executive Director
David Sarnoff Library
201 Washington Road, CN 5300
Princeton, NJ 08543-5300

609-734-2636
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