is not credit Edison disc line
. Although the larger, free-standing
cabinet models were well received Edison's faithful
customers, the low price models were heavily criticized as
inferior. During this period Edison gained
over patents and his researchers the disc project were
granted several more.. This, in
turn, was the logical extension the success the sapphire. The
disc development encompassed two periods intensive work:
from 1909-1912 produce the first models and then from
1912-1915 improve them. Yet this intense R&D effort had not
produced immediate success.
Compared with the research work done laboratories this
time, Edison's laboratory was embarking easier, and more
mundane task; the important trade secret the new Edison
product was the method fixing the piece diamond the
shank the reproducer. One dissatisfied jobber wrote that: "it does not
give satisfaction.IX-13
the focus R&D the phonograph; the diamond disc was an
offshoot the years development the cylinder phonograph
rather than change direction the Edison laboratory. The
only part the machine that could justifiably called an
innovation was the diamond point the reproducer.
After continually denying that was going introduce
a disc machine, the Company announced the Edison disc
phonograph 1913.. Yet took more than two more years to
introduce whole line disc machines, and even these models
were not fully satisfactory, especially Thomas Edison
