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16
Programmable
Frequency Match
Filter
The Truth about Bass and The
Programmable Frequency Match
Filter
Now that digital audio is the favorite musical source,
there’s more low bass running around in a typical system.
Low bass injects large amounts of power into ANY kind of
speaker — up to 60% of your amplifier’s output is being used
to reproduce frequencies under 110Hz. That can really tax
a system, which is driving multiple speakers from a single
amplifier channel. The second problem is that bass produces
heat in the speaker. If more heat is built-up than the speaker
can dissipate, the driver coil can literally go into meltdown
(or worse).
In addition, ultra-low bass and small speakers don’t
always get along, ESPECIALLY when you DO have ample
power. The low bass music content can cause over-excursion:
The speaker cone attempts to travel farther than its physical
limits, potentially causing damage (in some cases you can
actually hear a clacking sound!). Even before destruction sets
in, there are other problems with feeding super-low bass to
small speakers. Most bookshelf and in-wall loudspeakers are
2-way systems. That means that the woofer also handles a
large part of the critical midrange area. When the woofer is
bashing around trying to reproduce unrealistically low bass,
its ability to produce midrange is compromised due to inter-
modulation distortion. So not only don’t you get low bass, you
get lousy vocal and instrumental reproduction.
Pragmatically, it boils down to this: If you want ultra-low,
foundation-shaking bass from an in-wall speaker, you should
add in a separate subwoofer, a somewhat expensive ap
-
proach. A more economic approach is to equalize the speaker
for maximum low bass output WITHIN IT’S PRACTICAL
RANGE and eliminate lower frequencies which either can’t
be reproduced or which incite excessive cone travel.
The equalization part is handled by the Architect Model
210’s 45Hz control. The prevention part is handled by the
Architect’s Programmable Frequency Match (PFM) filter
circuitry. While it may seem surprising, actually cutting off
some of the lowest bass, will make the bass sound cleaner,
punchier and even louder.
