Sherbourn PT-7020A, Owner'S Manual

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The PT-7020A can be configured for one or two surround
back speakers. Ideally, all the surround speakers should be
of the same make and model, and fitted at similar heights
to produce a smooth continuous sound field. If you are
connecting one surround back speaker, connect its amplifier
input to the PT-7020A LEFT CHANNEL SURROUND
BACK output. Place the speaker behind your listening
position.
Subwoofer Location
The PT-7020A has two subwoofer outputs, the unbalanced
RCA output and the balanced sub output.
Placing the subwoofer in a corner usually creates the best
possible situation for the sound to speak to the room,
allowing even distribution of the bass frequencies. Often
the corner that offers nearby placement to the front speakers
may yield the best results, but you should try several
locations before settling on just one.
The best location for a single subwoofer can be found by
playing a couple of different low frequency test tones (or
some music with heavy sustained bass passages) and
proceeding with the following easy 1-2-3 process:
1. Place the subwoofer right on the seat of your couch or
listening chair.
2. You can then either run the calibration (noise) signal
through it, or simply plug the analog outputs of a CD player
directly into your subwoofer’s low-level inputs. Turn down
the subwoofer’s volume level before turning on the CD,
then play the test tones or some music with heavy sustained
bass passages.
3. Walk around the room, standing in all the positions where
you might be able to place the subwoofer. Again, this is
usually near the corners of the room. Try locations fairly
close to the front speakers.
Try a few different setups to determine where in the room
the bass output from the subwoofer sounds the loudest.
Shut things down and install the subwoofer there. This is
the best position for the subwoofer. The bass will sound
the best when you are sitting in your normal listening
position.
If your subwoofer seems to sound best when it is near the
front speakers (often the case), keep in mind that most
television sets may not react well to the subwoofer if it is
not built specifically for use in a home theater application.
While most front Left/Center/Right speakers do have
shielding when intended for use in a home theater
application, subwoofers are not always magnetically
shielded and may damage the television if placed too close.
If you want to check if this will be a problem, select an
unused video input on the television to bring up a single
color screen. If you see any color distortion anywhere on
the screen, an unshielded speaker is too close to the screen
and should be moved away from the television until the
color distortion disappears.
Note - most powered home subwoofers feature a phase
control with a range between 0-180 degrees. This is present
so that in situations where the optimum location is not
particularly desirable, you can locate the subwoofer
elsewhere nearby and make a slight adjustment to the phase
so that is sound arrives to the listener at the same time as
the other speakers. Ideally, sound arriving at the same time
is what allows the subwoofer to create the illusion of the
main speakers making the bass. This is what enhances the
listening experience.
Bass Management
Unlike higher frequencies, it is difficult to discern exactly
from which direction lower bass is coming.
The PT-7020A has a bass management system which takes
advantage of this effect. It allows you to choose whether
your speakers will play the full frequency range or if the
bass will be redirected to the subwoofer. The advantages
of redirecting the bass to a subwoofer include the following:
ƒ
The overall bass of the system is improved as subwoofers
are specially designed for this frequency range.
ƒ
The subwoofer can simultaneously play the bass from
all the speakers, in addition to its own low frequency
effects channel (LFE).
ƒ
There is no loss in perception of the position of movie
or music sound effects, as the ear cannot easily locate
the position of low frequency sources.
ƒ
Smaller speakers can be used for main front, center and
surround, as they do not have to reproduce the low
frequency range. This leads to a saving in speaker
expense and room space. A subwoofer is required if the
front speakers are set to SMALL.
ƒ
Your amplifiers do not waste power reproducing the low
frequency range when using a powered subwoofer.
Nearly all home audio subwoofers are self powered.
The Sherbourn room correction and speaker setup system
will set all your speaker sizes, distances and crossovers.
These can also be set manually to tailor the settings to
your specific needs.
Dolby Digital and DTS modes are designed especially for
complete systems with front, center, and surround speakers
and subwoofers. You need all of the speakers to get the
best performance from your Home Theater. If you do not
have a subwoofer connected, then you should not use the
bass management system (so set all of the speakers to
Large). Without a subwoofer, you will be missing the 5.1
LFE (low frequency effects) information.