VANDERSTEEN 3A - SPEAKER PLACEMENT; ODD DIMENSIONS PLACEMENT

Vandersteen speakers will produce excellent, satisfying sound
placed almost anywhere in a room. With all the possible variables
in room layout, there are no magical formulas for determining the
best speaker placement in every room. Since every room is
different, we recommend that you try the speakers in every
domestically acceptable location to find where they sound the
best in your particular listening environment. The following
sections contain suggestions that may be helpful in your
placement experiments.
Speaker Placement
Problems can arise when you attempt to place a
given loudspeaker, either front radiating or dipole, into
a typical domestic environment. These problems are a
function of the physical dimensions of the room. The
room’s dimensions dictate where in the room a node or
anti-node will occur. Frequency response dips and
peaks caused by nodes and anti-nodes can easily over¬
whelm the inherent accuracy of a loudspeaker.
If, for example, you place a loudspeaker with excel¬
lent frequency response characteristics in the corner of
a room, you will increase response below about 200Hz
by 6dB. This particular condition is a worst case ex¬
ample, but similar conditions apply throughout the
room to some extent.
Odd Dimensions Placement
Research on speaker placement has produced a
method for reducing the nodes and anti-nodes in many
rooms by positioning the loudspeakers on the odd
dimensional intersections of the room. The odd dimen¬
sional intersections are the intersections of the imagi¬
nary lines you would draw if you divided the length of
your room and the width of your room by odd numbers.
As an example, we will use a rectangular room
measuring 14 feet wide by 18 feet long. We’ll assume
that you want to set the speakers on one of the short
walls, although this method works equally well for long
wall placement.
The first step is to take the length of the room,
(18 feet in our example) convert it from feet to inches,
(18x12 = 216) and divide the result by odd numbers.
216 divided by 3 is 72 (all to the nearest inch)
216 divided by 5 is 43
216 divided by 7 is 31
216 divided by 9 is 24
216 divided by 11 is 20
216 divided by 13 is 17
(And so on, eventually the lines start to pile
on top of each other or the speaker runs into
the wall.)
The results are the distances in inches that the
center of the speakers can be placed into the length of
the room, away from the wall behind them, to minimize
nodes and anti-nodes.
Now we can graph these odd dimensions distan¬
ces on a drawing of the room. We only need to graph
them for the wall where we intend to place the
speakers.
We use the same method to figure how far the
centers of the speakers should be from the side walls.
We take the width of the room, (14 feet) convert it from
feet to inches, (14 x 12 = 168) and divide the result by
odd numbers.
168 divided by 3 is 56 (all to the nearest inch)
168 divided by 5 is 34
168 divided by 7 is 24
168 divided by 9 is 19
168 divided by 11 is 15
The results of these odd number divisions are the
distances in inches that the center of each speaker can
be placed into the width of the room, away from the
side wall, to minimize nodes and anti-nodes.
Now we can graph these odd dimensions distan¬
ces on a drawing of the room.
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Model 3A Operation Manual