The daily banner. (Cambridge, Md.) 1897-2008, 1921-03-04
PRESIDENTS ADDRESS
TO BE HEARD HALF Mile
New Sounding Device Designed BY
Experts OF The G. & p, Telephone
Company Will Carry Sound Long
Distance In The Open Air

For the first time in the history Of
the United States an inaugural ad-
dress will be heard in Washington
by everyone of the hundreds of
thousand of men and women who
will crowd the broad open space
which stretches for fifteen hundred
| feet in front of the inaugural stand
at the Capital Building. The rea-
son for this is found in the loud
speaking devices which has been in
stalled for the benefit of the public,
and which is the only feature of the
entire simple inaugural ceremonies
outside of the taking of the oath. By
means of this device, which is hid
den from the eye, the human voice
is made to carry half a mile under
perfect conditions.
The apparatus is a system of mo-
tors generators, wires, transmitters
amplifiers and other electrical ma
ehinery designed by the experts OF
the Bell Telephone System, which
has contributed the speaker to the
inaugural ceremonies for the benefit
of the public. 1t is not a CONNER
cial device, it is not patented, nor is
it for sale or for rent To the eX-
perts, the system is the exposition
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, have simply brought into
play some of the marvellous discoy-
cries and developments of the Bell
laboratories.
Although there are three rooms
full of machinery and electrical de-
vices in connection with the loud
speaker, none of it is in evidence,
and the huge horns through which
the speech will be heard are camou-
f1aged by being made part of the
roof of the speakers stand. So far
as the speaker himself is concerned
he will see nothing Of the apparatus
except small transmitter boxes which
will be set somewhere in front ana
to the sides of his speaking desk, so
that his voice will be caught in the
workings of the loud speaker no mat
ter which way be turns.
When the President Elect speaks,
his voice will generate energy by
means of the transmitters. This
energy is transformed by wires to
the complex apparatus now being in
stalled under the Capitol steps. The
energy is led into a little glass bulb,
which the engineers call vacuum
tubs amplifier," the function OF
which is to receive energy, multiply
it and send it on to the other ampli-
r Tnanhoc q OF sufficient
to turn it loose in voice form through
the ridden horns out to the distant
crowds.
While the speaking is in progress
a dozen Bell experts will be watch
ing each bit of apparatus. There
will be men at certain points on the
Capitol plaza connected with the ma
ehinery rooms by telephone, to re-
portto the men at the amplifier. The.
e~Srk1ng loud speaker requires o
crew as large as small vessel.
The voice when it emerges from
the horns, is almost an exact dupli-
cation of the original, but greatly in
creased in power 1t is impossible
for the loud speaking system to OBJ
tain an amplification of several mil
lion times without great distortion
of the original wave form.
The mouths of the hidden horns
are depressed just enough so that
the audience near at hand within
range of the speakers voice direct,
hear very little fro mthe horn, those
further away hear both the speaker
and the loud speaking system. those
further away hearing the horn only.
1t might seem that this additional
source of sound might create a
double effect Or an unnatural effect,
but it does not. The sound from the
horn is exactly in phase with the
speech, and almost exactly the same
quality. At any point where the
sound from the horns is heard, it is
practically impossible to tell that
one is not listening to the speaker
himself