Technology in A/V receivers has increased in advancement and sophistication
with the introduction of formats such as Surround EX,
™
DTS
®
6.1 Discrete,
SACD and DVD-Audio. Speaker manufacturers have increased their offerings
in response to these new formats, but most competitive A/V receivers have not
updated their bass-management systems to accommodate the wide range
of choices. For example, many receiver models still apply crossover points globally,
rather than in individual groupings.
Triple Crossover System
Harman Kardon’s newest receivers – the DPR 1001, AVR 7200, AVR 525 and AVR 325 – offer an advanced and
versatile Bass Manager, which allows the crossover to be set to one of six specific frequencies for each of three
different speaker groups (see Figure 1). Within the same surround mode input setup, the six choices are 40Hz,
60Hz, 80Hz, 100Hz, 120Hz and 200Hz. Therefore, one could set the left/right fronts to 80Hz, the center to 100Hz
and the surrounds (side and back) to 200Hz. Also, when the high-pass-frequency point is selected, it automatically
sets the proper matching, compatible low-pass-frequency point (to the LFE out) to ensure that none of the
low-frequency information is lost and that all sound is outputted properly to the assigned channels. (Note that the
software is run at 48-bit resolution using 2nd-order high-pass filters and 4th-order low-pass filters [Linkwitz-Reily].)
Triple Crossover and Multichannel
Digital Bass Manager
Figure 1.
Harman Kardon 7.1-Channel Home Theater System Using Triple Crossover
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