gets e HEADACHE
out of its SYMPHONIES
By Norman Siegel
HE broadcasting of symphonic
music is an exciting and serious
business. It offers one of the
knottiest problems the radio net
works have to face.
To begin with, most symphonic pro
grams are “remote control” broadcasts.
That is, when you hear the Cincinnati,
Cleveland, Boston or Detroit Sym
phonies you are not hearing them from
radio studios in those cities, but you are
hearing them from concert halls under
conditions which are often bad for
broadcasting.
Some of these orchestra halls were
built long before the days when any
thing was know'n about acoustics, much
less radio broadcasting. Of course the
age of an auditorium may not mean
that it is not acoustically perfect. Thej
Academy of Music in Philadelphia, for
instance, which was built in 1847, is
considered by experts to be one of the
finest halls for symphonic concerts in
America. New York s Carnegie Hall,’
too, is an ideal concert hall, and that’s
an old standby of the Metropolis. ° j
However, when the broadcasters
move in and begin setting up_ their
wires and microphones, they run into a
number of problems. In planning for
the Cincinnati Symphony series under
the direction of Eugene Goossens, Co
lumbia engineers discovered that their
microphones picked up a disconcerting
echo in the Cincinnati Music Hall.
It seems that1 the walls and ceilings
of the hall are of hard plaster construc
tion, causing the sound waves to bounce
back instead of being absorbed. The
microphone hanging somewhere about
row H would catch these sound waves
on the rebound about three seconds
after they originally came from the or
chestra. At the same time pew sound
waves from the orchestra would be
coming into the microphone. The re
sult was a hazy waving distortion of
too*.
'T’HIS might have been corrected by
placing the microphone closer to the
orchestra, something that's often done
to escape an echo. But they couldn't
get too near the Cincinnati Orchestra,
for in concert arrangement it spreads
out over a radius of 65 feet. A micro
phone placed too close would pick up
only the central section and miss the
outskirts.
Therefore, there was only one solu
tion to this problem—a new type of
microphone. It is known as the “uni
directional microphone,” and is now
also used on Detroit Symphony and
Andre Kostelanetz Orchestra programs.
The mike is closed at the back. Un
like the “bi-directional” microphone,
which picks up sound wav«s at both
front and back, it has a pick-up angle
of but 120 degrees. That means that
spreading over the front and sides of
this microphone is an area of sensitivity
in shape something like a crescent slit
across the front of a bomb. This curve
faces the orchestra, thereby eliminating
all echo.
The Detroit Symphony programs on
Sunday night offer another problem.
During this broadcast, which originates
at Masonic Temple in Detroit, the audi
ence is part of the program. In most
•other symphonic broadcasts the audi
ence merely listens and applauds, but
in Detroit, the audience of almost 5000
persons stands up and sings some fa
mous and familiar hymn at the end of
the program.
This means that the engineer han
dling the broadcast has to worry about
several different “live areas.” When
the orchestra is playing, he turns on the
“uni-directional” microphone. When a
soloist is playing or singing with the
orchestra, he has to blend the soloist’s
mike with the "uni-directional” one of
the orchestra. When the audience
chorus is singing, a number of other
microphones are turned on to pick it up.
Part of (he born section of the Detroit
Symphony orchestra, above. Radio dis
torts the tone of these instruments un
less they are played very “mellowly.M
.At right, Eugene Goossens, di
rector of the Cincinnati Symphony, who
discovered a disconcerting echo when
his orchestra first went on the air
waves.
T EOPOI.D STOKOWSKI S Philadel
* ' phia Orchestra broadcasts its week
ly Friday night program from a small
hall in which there is a minimum of
audience. It is the small chamber music
auditorium for students at the Curtis
Institute of Music.
Here the greatest difficulty is the
width of the room. The musicians oc
cupy the space where the audience
would normally sit. for there is not
enough room on the stage. Unless they
are all seated correctly their instru
ments will play into the wall, or will be
facing so as to cause reverberation.
In an effort to eliminate this, Stokow
ski spreads the orchestra out in a sort
of wide battalion.
Carnegie Hall, where the New York
Philharmonic broadcasts its programs,
presents few problems to the engineer
on the job. The acoustics are so good
that an ordinary microphone is used tc
pick up the program. The microphone,
hung about 25 feet above the stage
level and inclined at an angle of about
15 degrees downward and five degrees
toward the first violins, registers the
concert as it would sound to a man
seated in the choicest seat in Carnegie
Hall—about Row H Center.
Another problem that faces radio in
airing symphonic programs is the mat
ter of the set-up of the orchestra.
The audience witnessing these con
certs expects .to see the orthodox or
chestral arrangement. As a result the
microphone has had to adapt itself to
the exigencies of this set-up. It has
only been in the past season that the
orchestral set-up of the Philharmonic
has been varied for broadcasting.
The basses and timpani, instead of
running along the back of the orches
tra, have been pushed to the farther
side of the stage.
Engineer A. B. Chamberlain claims
the acoustical reason for this change is
that basses, timpani, and bassoons emit
a low frequency vibration which is
non-directional. These sound waves
don’t travel in a stra.ght line but slug
gishly spread out in all directions. They
are bound sooner or later to hit a hard
surface somewhere which causes dis
tortion and spoils the entire concert.
Many other instruments could well
be moved around and rearranged, were
it not for the presence of the audience
The piano has to be carefully watched
for broadcasting purposes. The same is
true of the harp.
‘ timing the concert. The broadcaster
can attend the rehearsal of the orches
tra but he can not be exactly sure of
the timing, for at such rehearsals the
conductor is working over the music,
stopping and starting again, and it Is
seldom that the piece is rehearsed
through without a number of interrup
tions.
As a result of not being able to clock
the program before it goes on the air,
the broadcasters use the intermission of
the program as a safety valve against
running over or under the program's
allotted time. |
Symphonic broadcasting is still in the
research state. Engineers have made
great stride in the last few years in
reproducing with greater and greater
fidelity the pure quality of the instru
ments, in eliminating echo, in overcom
ing the difficulties of the concert halL
But there is still much to be done.
For instance, the full volume of tho
symphony orchestra can not yet be car
ried by the airwaves. It is too im
mense, too powerful. If the engineers
tried to transmit it ail, the broadcasting
equipment would be so overloaded as
to cause terrible distortion and dam
age to the large water-cooled tubes in
the transmitting plant.
The present solution of the problem
has been to compress the volume of the
original orchestra to the volume which
the radio equipment is capable of car
rying. This is left to the engineer who
handles the program.
there is also the problem of