SV Subwoofers
Page 6
ting ALL speakers to “Small” works best. Let your sub make the bass! Also, is
your subwoofer turned “ON”? We don’t mean “is your subwoofer
amplifier
on?” (that’ll be important later too) but rather,
is your receiver sending a bass signal
to your sub amp?
This can only happen if you say “Yes” (or “ON”) in the
“Subwoofer” selection during the all-important setup menu of any typical Dolby
Digital/DTS capable receiver. If you have a choice of “crossover points” for your
bass, usually “80Hz” works best, unless you have unusually small main speakers.
•
I
s your receiver connected to the sub amp?
Use a well-shielded RCA cable
(sometimes called a “patch cord”) to connect the subwoofer output of your DD/DTS
receiver to
either
input jack of your subwoofer’s dedicated amplifier. As mentioned
earlier, you’ll need to “split” the bass signal with a “Y Cable” if you bought a pair
of subs. You only need feed
one
of the two inputs (either Right or Left) of any sin-
gle Powered Box SVS however.
•
I
s your Radio Shack ® sound pressure level (SPL)
meter ready?
This tool is simply
vital
to proper home thea-
ter audio setup. It’s akin to a tire pressure gauge for your car.
The manual which comes with the SPL meter is excellent; we
recommend you read it entirely. Haven’t got the meter yet?
Head down to your neighborhood Radio Shack ® and snag
one. We prefer the analog instead of the digital display model
but both work well. Ask for part number
#33-4050
. At about
$45, it’s a bargain. Proper configuration
without
this meter is
practically
impossible
.
Getting ready to start now: Make sure your receiver/processor master volume is set
at “00 dB” or some other easy to remember reference level. Finally, ensure your SVS’s
volume control is set no more than 1/4 to 1/3rd up at first. It’s also critical to check the
subwoofer level control of your surround receiver before you begin the test tones. Set it
to no higher than “-5 dB” initially (that’s one quarter way up, given a typical receiver’s
subwoofer channel level limits of –10 dB to +10 dB) . Your LFE “trim”, if you have one,
should be set to 0dB to start (that’s full up) but this can be dialed down later to tame
peaks if needed. IMPORTANT: Turn off ANY sound-field processing modes, “peak
limiters”, “mid-night mode” etc.
Set the SPL meter to “Slow” and “C-weighting” (turn
the range dial to 70dB).
Now play your receiver's internal test tones so you have something to
measure with your SPL meter. Better yet, buy a calibration disk, such as the Video
Essentials, Sound and Vision HT Tune Up, or Avia DVDs. A test disk’s tones ensure
your entire signal path, from the DVD player to your speakers, is set correctly. Whatever
you use, when the tones start alternating from speaker to speaker (watch your sound me-
ter now), set each full range speaker’s level to about 75 dB (or 85dB if using Avia or
S&V), by using the receiver’s dedicated channel controls (leaving receiver’s master vol-
ume the same). We recommend you turn down the receiver’s subwoofer output level
before you significantly lower your sub’s volume/gain control. This helps keep input
distortion to a minimum. You should not be set much lower than –5 dB however, since
some adjustment room is needed to lower bass as needed. If your subwoofer reading is
still too high then turn down the sub’s amp volume a little with each run.