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CHAPTER 4: INTEGRATING ACHERON LF LOUDSPEAKERS

INTEGRATING ACHERON LF LOUDSPEAKERS

To meet the SPL and low frequency headroom requirements
of large rooms, the Acheron 100 or Acheron 80 can be
daisy-chained with the Acheron LF loudspeaker, creating a
system with three low frequency drivers and one high fre-
quency driver. Adding an Acheron LF yields approximately a
10 dB boost in the low frequency range, depending on load-
ing conditions and room acoustics.
The Acheron LF has been carefully designed so its fre-
quency and phase responses compliment the Acheron. The
Acheron LF has the same low end frequency response as
the Acheron (38 Hz) and rolls off at 320 Hz to avoid any
interference in the crossover region of the Acheron.
At 38 Hz to 150 Hz, all three low frequency drivers are
active. At 150 Hz, the bottom Acheron LF low frequency
driver rolls off.
At 150 Hz to 300 Hz, two low frequency drivers are
active: the top Acheron LF driver and the Acheron low
frequency driver. At 300 Hz, the top Acheron LF low fre-
quency driver rolls off.
At 300 Hz to 580 Hz, only the Acheron low frequency
driver is active, which enables a smooth crossover to the
high frequency driver.
This unique multi-way, gradated design offers smooth cov-
erage and maximum low-frequency impact with all drivers
active at the lowest frequencies and each rolling off, one at a
time, via the internal active crossover. This technique elimi-
nates interference between drivers that would otherwise
occur at shorter wavelengths, enabling the system to main-
tain ideal polar, phase, and frequency responses throughout
the low and low-mid operating ranges. As a result, the sys-
tem can deliver the necessary power to completely fill a
large theatre.

Achieving a Flat Frequency Response with an

Acheron / Acheron LF Stack

When the Acheron and Acheron LF are daisy-chained (using
the Loop output connector on the user panel) an approxi-
mate boost of 10 dB at 110 Hz results, depending on the
loading conditions and room acoustics. To achieve a flat fre-
quency response in this configuration, a single parametric
filter with the following characteristics can be applied to the
signal:
CAUTION: When daisy-chaining Acherons and
Acheron LFs, make sure the audio cables are
wired correctly to avoid polarity reversals.
Acheron 100 with Acheron LF
Acheron LCR System with Acheron LFs
Low frequency
Low frequency
Low frequency
High frequency
Acheron LF
Acheron 100
Screen
Right
Center
Left
Filter type Parametric
Frequency 110 Hz
Bandwidth 2 (Q = 0.6667)
Amplitude –10 dB
!