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Instruction Manual

the bass from that channel to the subwoofer. If your processor/receiver
offers this choice, all Atlantic Technology satellite speakers should be set
to Small, regardless of their size.
For those of you who may have heard otherwise, the choice of Large or
Small is not a matter of opinion, preference, taste, or based upon the
phases of the moon. So please ignore any and all free and helpful (and
many times incorrect) advice and set them to Small. In fact, the vast
majority of speakers on the market today should be set to small. As a rule
of thumb, if any satellite speaker in your system doesn’t have a 10-inch
diameter or larger woofer, it most probably should be set to Small, as far
as Bass Management is concerned.

The PHASE Control

A subwoofer operating out of phase with the rest of
the system won’t provide optimum low frequency
performance. Also, the correct subwoofer phase can
help compensate for room acoustic anomalies. There-
fore, a PHASE switch that will alter the phase of the
PedWoofers is provided on the amplifi er. It has 4 posi-

tions (0°,90°,180°,270°) for added fl exibility. To set the PHASE control,
insert the supplied Atlantic Technology/Sencore Test and Training CD in
your CD/DVD player and select the broadband bass test tones on Track
16. Have someone sit in the prime listening position to evaluate the sound.
Pay particular attention to the transition of bass from the subwoofer to the
satellite speakers. You can also listen to a musical source such as a CD or
DVD, with strong bass content that spans the range from deep bass to mid
bass (a well recorded jazz disc with someone playing a full stand up bass is
always a good choice). It’s best not to use a “one note” special effects track
like a big explosion or dinosaur stomping to test the subwoofer. Experiment
with the position of the PHASE control(s) to get the best transition from
sub to satellites. We suggest you unplug the input to one PedWoofer chan-
nel at a time to set the PHASE control for the other channel (always turn off
the power before unplugging or plugging in any connections). It should be
obvious which is the correct setting. In particular, there will be a smoother,
more integrated transition between the satellites and the subwoofer when
they are properly phased.

Parametric Room Equalizer (EQ)

In order to optimize the performance of your PedWoofers the parametric
equalizer should be utilized. The built in Parametric EQ(s) allow you to
select the frequency you want to adjust, and how wide a band on either
side of that frequency you’re going to adjust with it. They are designed
specifi cally to remove (turn down) unwanted peaks in the bass. The
procedure is fairly simple: the included Atlantic Technology/Sencore
Test and Training CD is used along with a SPL meter to defi ne the single
largest bass peak at the prime listening position and then reduce it with
the Parametric EQ.
The test and setup CD also includes a wealth of general information con-
cerning sound reproduction and home theater, in addition to the test
tones.

Although the test tones can be used to set the EQ “by ear” we very

strongly recommend using a Sound Pressure Level meter or a Real Time
Analyzer to set the Parametric EQ.

Adjusting the Parametric EQ Using a Meter or

Real Time Analyzer (RTA)

IMPORTANT NOTE:

During all set up operations except setting the

Phase control it will be benefi cial to shut off or disconnect all the
speakers except the PedWoofers.

It’s important to complete the preceding steps regarding speaker setup
before adjusting the parametric equalizer. Once they’re complete, insert
the Atlantic Technology/Sencore Test and Training CD into your CD or
DVD player and go to Track 16, which is a full range test signal includ-
ing all bass frequencies from 20Hz to 120Hz. Set the BASS LEVEL of a
single 8200 PedWoofer to 75dB at the primary listening position. With the
6200 system set the total PedWoofer output to 75dB at the prime listening
position. If you are using an RTA, set it to at least 1/6

octave resolution

and slow response (Use slow response to allow the meter to average the
standing waves that build up in the room). Continue using Track 16 to
observe the overall response of the PedWoofer. It is highly likely that you
will fi nd at least one signifi cant peak (between 20Hz and the crossover
point set on the amplifi er or in the processor). Write down the center fre-
quency of the peak, how wide the peak is (by noting the upper and lower
frequencies where it starts and stops) and how large it is, in dB.

Begin setting the para-
metric EQ by adjusting
the FREQUENCY control
to the approximate cen-

ter frequency of the peak.
Next adjust the WIDTH
control to the approximate
width of the peak. Note
that the WIDTH control is

calibrated in octaves. An octave is a doubling or halving of any chosen
frequency. For example, if the chosen frequency is 40Hz, 1 octave higher
would be 80Hz, and one octave lower would be 20Hz. Since the WIDTH
control ranges from 0.2 octave to 1.5 octaves you see that you can adjust
from a fairly narrow band to a fairly wide band on either side of the center
frequency. Next, set the ATTENUATION control to the approximate minus
dB value to compensate for the peak. Measure the bass response again
and see how much you have reduced the overall peak. You may need to
fi ne-tune the controls to smooth the response as much as possible.

Setting the Parametric EQ Using an SPL Meter

If you only have an SPL meter, set the meter to C Weighting and Slow
response. Set the PedWoofer(s) output to 75dB at the listening position
as outlined above using Track 16 of the test disc. Sit in the prime listening
position with a pencil and paper play Tracks 1-15 sequentially to measure
the subwoofer response. Take enough time with each measurement to
allow the meter to stabilize. Write down the measured level for each fre-
quency, covering the range from 20Hz to the crossover point selected on
the subwoofer amplifi er or in the receiver/processor. Once again, you will
most likely fi nd one or more signifi cant peaks in the bass response. Pro-
ceed as detailed above to reduce the largest peak as much as possible.

System Setup and Operation

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