Audio Control Architect 100, Installer'S Manual

The Architect

Model 100 & Model 200

Installer’s Guide

The Truth About

Bass & The

Programmable

Frequency

Match Filter

15

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 100Hz.
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 intermodulation 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, founda-

tion-shaking bass from an in-wall speaker, you should add in a separate
subwoofer, a somewhat expensive approach. A more economic ap-
proach 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

tm

 Model 200’s

45Hz control. The prevention part is handled by The Architect

tm

 Model

100 and Model 200’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.

AudioControl’s Programmable Frequency Match circuit is an

adjustable subsonic filter which cuts off low frequencies. The PFM
filter’s cut-off point is adjustable via a small screwdriver adjustment on
the rear of The Architect

tm

 Model 100 and Model 200. When you

receive your unit, it is programmed with a 40Hz bass cut-off. Depend-
ing on the application, your custom installer or dealer may suggest
changing the filter frequency. Don’t let ego get in the way and set the
PFM too low because somebody thinks that a 6" woofer should be able
to play down to 20Hz.

Highpass filter control on back
panel