MartinLogan pmn Speaker User Manual


 
Placement 7
Imaging
In their final location, the Clarity’s should have a stage width
somewhat wider than the speakers themselves. On well-
recorded music, the instruments should extend beyond
the edges of each speaker to the left and to the right, yet a
vocalist should appear directly in the middle. The size of
the instruments should be neither too large nor too small.
Additionally, you should find good clues as to stage depth.
Make sure the vertical alignment, distance from the front
wall, and toe-in, is exactly the same from one speaker to the
other. This will greatly enhance the quality of your imaging.
Bass Response
Your bass response should neither be one note nor too
heavy. It should extend to even the deepest organ pas-
sages, yet it should be tight and well defined. Kick-drums
should be tight and percussive—string bass notes should
be uniform and consistent throughout the entirety of the
run without any booming or thudding.
Tonal Balance
Voices should be natural and full, cymbals should be
detailed and articulate yet not bright and piercing, pianos
should have a nice transient characteristic and deep tonal
registers as well. If you cannot attain these virtues, read the
section on Room Acoustics (pages 8–9). This will give
you clues on how to get closer to those ideal virtues.
Final Placement
After obtaining good wall treatments and the proper angle,
begin to experiment with the distance from the wall behind
the speakers. Move your speaker slightly forward into the
room. What happened to the bass response? What hap-
pened to the imaging? If the imaging is more open and
spacious and the bass response is tightened, that is a supe-
rior position. Move the speakers back six inches from the
initial setup position and again listen to the imaging and
bass response. There will be a position where you will have
pinpoint imaging and good bass response. That position is
the point of the optimal placement from the front wall.
Now experiment with placing the speakers farther apart.
As the speakers are positioned farther apart, listen again,
not so much for bass response but for stage width and
good pinpoint focusing.
Your ideal listening position and speaker position will
be determined by:
•Tightness and extension of bass response
•Width of the stage
•Pinpoint focusing of imaging
Once you have determined the best of all three of these
considerations, you will have your best speaker location.
The Extra “Tweak”
A major cable company developed the following procedure
for speaker placement. As a final test of exact placement,
use these measurements for your speakers placement, and
see what can happen to the ultimate enhancement of
your system’s performance. These two basic formulas will
determine optimum placement of your speakers to minimize
standing waves.
1 Distance from the front wall (the wall in front of the listening
position) to the center of the curvilinear transducer. To
determine distance from the front wall, measure the height
of your ceiling (inches) and multiply the figure by 0.618
(i.e., ceiling height in inches x 0.618 = the distance from
the front wall to the center of the curvilinear transducer).
2 Distance from the side-walls to the center of the curvilinear
transducer. To determine distance from the side walls,
measure the width of your room (inches) and divide by
18. Next, multiply the quotient by 5 (i.e., room width in
inches/18 x 5 = the distance from the side-walls to the
center of the curvilinear transducer).
Enjoy Yourself
The Clarity is a very refined speaker and benefits from care
in setup. With these tips in mind you will find, over your
months of listening, that small changes can result in
measurable differences. As you live with your speakers, do
not be afraid to experiment with their positioning until
you find the optimal relationship between your room and
speaker system that gives to you the best results. Your efforts
will be rewarded.
You are now armed with the fundamental knowledge of
room acoustics and the specific fundamentals of the Clarity
loudspeaker. Happy listening!