Introduction
For the first time, the new McIntosh XRT2K Loudspeaker
System is capable of reproducing the full dynamic range of
a symphony orchestra including pipe organ without audible
distortion. McIntosh Acoustic Engineers have refined the
line source Column Loudspeaker concept and the XRT2K
Loudspeaker System is the 6th in a generation of that pat-
ented design
. It provides
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superior quality midrange
and high frequency sound
reproduction in a full
range system.
The High Frequency
Section utilizes a patented
Column Design
with mul-
1
tiple two inch Midrange
Inverted Titanium Dome
Drivers and three-quarter
inch Titanium Dome
Tweeters. Refer to fig-
ures 1 and 2. Since the
audio power fed to a
column is distributed
among all the drivers,
each driver does not
have to work as hard,
resulting in greater
power handling capa-
bility and a dramatic
reduction in distortion.
The Sound Waves from
the Column produce a
Cylindrical Wave Front
with a stable symmetrical horizontal sound dispersion while
minimizing undesirable floor and ceiling reflections that de-
tract from a
stable
sound im-
age. Refer
to figure 3.
In the illus-
tration, the
Loud-
speaker on
the left side
produces a Cylindrical Wave Front and the Loudspeaker on
the right side produces a conventional Spherical Wave
Front.
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COLUMN Pat. No. 4,267,405
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Figure 1
Figure 2
Figure 3
The Low Frequency Section of the System consists of
six 12 inch Aluminum Cone Woofers capable of long cone
excursions. The sound produced has very low levels of har-
monic dis-
tortion and
a fre-
quency re-
sponse
down to
16Hz.
They have
a large mo-
tor assem-
bly made
with High
Tempera-
ture
Neodymium magnets with inherent shielding to greatly re-
duce any external magnetic field. Refer to figure 4. The
woofer design also utilizes an aluminum shorting ring, cop-
per capped pole piece, three inch diameter voice coil and
two cone centering devices. This results in lower distortion
due to more linear magnetic flux in the voice coil gap. A
good example of this low distortion is incredible smoothness
and effortless clarity in the reproduction of the human voice.
The Crossover Networks used in the XRT2K Loud-
speaker System are designed to ensure a smooth frequency
response over the entire audible range. The Low Frequency
Crossover Network is a quasi-second order design. Refer to
figure 5. Along with the column arrangement, this network
acoustically sums to a fourth order Linkwitz-Riley low
pass. The Midrange Crossover Network is a second order
high pass and low pass design. Refer to figure 6. Acousti-
cally, the high pass sums to a fourth order Legendre and the
Figure 4
Figure 5