Smyrna times., 1921-03-09
HARDING USED LOUD SPEAKER
Device Installed Which Threw Voice
Over Vast Distance on March 4.

Device Installed Which Threw Voice |
Over Vast Distance on March A.
For the first time in the history of
the United States an inaugural adj
dress was heard by everyone of the
hundreds of thousands of men and
women who crowded the broad open
space which stretched for fifteen hum
dred feet in every direction around
the inaugural stand in front of the
Capitol Building. The reason for this
was found in the loud speaking device
which was installed for the benefit of
the public, and which was the Only
feature of thee entire simple inaugural
ceremony. outside of the taking of the
oath. By means of this device, which
is hidden from the eye, the human
voice is made to carry half mile un-
der perfect conditions.
1t was a system of motors, genera
tors, wires, transmitters, amplifers
and other electrical machinery design
ed by the experts of the Bell Tele-
phone System, which contributed the
speaker to the inaugural ceremonies
for the benefit of the public. 1t is not
commercial device, it is not patent
ed, nor is it for sale or for rent. To
the experts, the system is the exposi-
tion of the development of everything
scientific in the telephone world, for
the principles involved are those of
the telephone and the engineers and
research men of the Chesapeake and
Potomac Telephone Company and the
American Telephone and Telegraph
Company, simply brought into play
some of the marvellous discoveries and
developments of the Bell laboratories.
All Apparatus Hidden
Although there were three rooms
full of machinery and electrical de-
vices in connection with the loud
speaker, none of it was in evidence,
and the huge horns through which the
speech was heard were camoufaged
by being made a part of the roof of
the speakers stand. So far as the
speaker himself is concerned he saw
nothing Of the apparatus except small
transmitter boxes which were sci
somewhere in front and to the sides Of
his speaking desk; so that his voice
: was caught in the workings of the
loud speaker no matter which way he
turned.
When the President-elect spoke, hi!
voice gathered energy by means o.
, the transmitters. This energy wa
- o.,oI - x,-;,.o- - 4I,o oo,,,,,l =,
apparatus installed under the Capito
steps. The energy is led into a lttl
: glass bulb, which the experts call
, vacuum tube amplifer," the function
9 of which is to receive energy, multi
: ply it and send it on the other ampli
fiers until it reaches a stage suficien
to turn it loose in voice form through
. the hidden horns out to the distan
: crowds.
v While the speaking was in progres:
: a dozen experts were watching eac
:, bit of apparatus. There were men q
i certain points on the capital plaz
= connected with the machinery room
by telephone, to report to the men q
: the amplifers. The working lou
II speaker requires a crew as large as
= small vessel.
IF Amplifies Millions of Times
The voice, when it emerges from tn
horns, is almost an exact duplicatio
he of the original, but greatly increase
at in power. It's possible for the lou
Sc speaking system to obtain an amplii
~ cation of several millions times witt
to out. great distortion Of the originl
en- wave form.
re The mouths of the hidden horns al
t. depressed just enough so that the al
p dience near at hand within range
he the speakers voice direct, hear vel
he little from the horn, those furth,
to away hear both the speaker and Il
nd loud speaking system, those furthe
in away hearing the horn only.
sw 1t might seem that this addition
no source of sound, might create do
or bic effect or an unnatural effect, but
les does not. The sound from the ho
tn is exactly in phase with the speec
of and almost exactly the same oualit