Jbl S4S User Manual

JBL SYNTHESIS®FOUR

S4S

LUSH-MOUNT

F
LOUDSPEAKER

Two units minimum

OWNER

’

S GUIDE

THANK YOU FOR CHOOSING JBL

®

For more than 60 years, JBL has been involved in every aspect of music and film recording and reproduction, from
live performances to monitoring the recordings you play in your home, car or office.

We’re confident that the JBL Synthesis loudspeaker you have chosen will provide every note of enjoyment that you
expect – and that when you think about purchasing additional audio equipment for your home, car or office, you will
once again choose JBL.

Please take a moment to register your product on our Web site at www.jblsynthesis.com. This enables us to keep
you posted on our latest advancements, and helps us to better understand our customers and build products that
meet their needs and expectations.

JBL Synthesis

INCLUDED
S4S

(1) Loudspeaker with grille
(6) Small grille spacers (for applications requiring one layer of wallboard)
(6) Large grille spacers (for applications requiring two layers of wallboard)
(6) Grille cups

IMPORTANT NOTE: A complete S4S loudspeaker system includes the S4S
in-wall subwoofer and the S4SBB back box, which must be purchased sepa
rately. A high-quality, external two-channel power amplifier, such as the JBL
Synthesis S800, is also required, and must be purchased separately. The
amplifier should be capable of outputting up to 500 watts per channel with
flat frequency response from 20Hz – 500Hz. Although this manual describes
installation with reference to all three components, they must be purchased
separately

.

2

Template and paint shield

-

SPEAKER PLACEMENT

Low-frequency sounds are normally omnidirectional, meaning the listener can’t tell where they are generated from.
However, frequencies between 75Hz and 150Hz can be localized, especially at higher volume levels. Positioning your
subwoofer as recommended will provide the most natural soundstage and imaging from your loudspeaker system.

It is generally recommended that you install your S4S in-wall subwoofer along the same wall as the front loud­speakers. The S4S subwoofer is not video-shielded and should not be placed near a video display. Installing the
S4S near a corner will tend to maximize low-frequency output. Be cautious when installing in a corner, to avoid a
“boomy” sound. Also take into consideration any unusual features of the room, such as an alcove, which may tend
to create a localized node that may affect bass response in that area of the room.

It is also recommended that the speaker be installed so that the bottom of the speaker is approximately 12" from the
floor. Using the S4SBB back box enclosure will ensure that the loudspeaker is installed at the ideal height. This is to
help with the low-frequency loading (bass reinforcement). This also helps hide the speaker in a less visible place. In
special circumstances it is acceptable to install the speaker at any height on a wall.

Remember that these are just guidelines. Since every listening room is different, JBL strongly recommends experi­menting with the positioning of your subwoofer prior to cutting the wall to obtain the most pleasing results in your
room. One technique that can help you find the ideal subwoofer location is to temporarily borrow a stand-alone sub­woofer and place it near the main listening location. Then move around the room and determine where you hear the
most pleasing bass performance. This would then be the ideal location for the subwoofer.

A single S4S subwoofer system meets THX
THX Ultra2

™

requirements for a 3000-cubic-foot room, two or more S4S subwoofer systems are required, using
a total of four woofers. For every additional 3000 cubic feet of room volume, it is recommended that one
additional S4S system be added.

When using two S4S in-wall subwoofer systems, you may need to be concerned about phase, as the sound waves
may cancel each other out. If bass response seems low
the (+) terminal on the amplifier to the (–) terminal on the speaker, and the (–) terminal on the amplifier to the (+)
terminal on the speaker.

®

Select requirements for a 3000-cubic-foot room. However, to meet

, try inverting the polarity on one subwoofer – i.e., connect

3

SPEAKER CONNECTIONS

Connection Tips

Speakers and electronics have corresponding (+) and (–) terminals. Most
manufacturers of speakers and electronics, including JBL, use red to denote the (+)
terminal and black for the (–) terminal. It is important to connect both speakers iden­tically: (+) on the speaker to (+) on the amplifier, and (–) on the speaker to (–) on the
amplifier. Wiring “out of phase” results in thin sound, weak bass and a poor stereo
image. With the advent of multichannel surround sound systems, connecting all of
the speakers in your system with the correct polarity remains equally important in
order to preserve the proper ambience and directionality of the program material.

If two S4S subwoofers are used, the wires for both speakers should be the same length. If one speaker is placed
closer to the amplifier than the other, hide the excess wire behind the wall. If bass response seems low, there may
be a phase problem, with the sound waves from the two subwoofers canceling each other out. If bass response
seems low, try inverting the polarity on one subwoofer – i.e., connect the (+) terminal on the amplifier to the (–)
terminal on the speaker, and the (–) terminal on the amplifier to the (+) terminal on the speaker.

To use the push-type terminals on the S4S baffle, depress the colored cap until the pass-through hole in the binding
post is revealed. While holding the cap down, insert the bare end of the wire, or a banana plug, into the pass­through hole. Release the cap and tug gently on the wire to ensure that it is secure.

To use the binding-post speaker terminals on the terminal cup located on the top panel of the S4SBB back box enclo­sure (sold separately), unscrew the colored knob until the pass-through hole in the center post is visible under the
knob. Insert the bare end of the wire through this hole, then screw the knob down until the connection is tight. The
hole in the center of each knob is intended for use with banana-type connectors.

Since the S4S is a passive loudspeaker, only speaker-level connections are available. Use the S4S with a high-quality
dedicated subwoofer amplifier as recommended by your JBL Synthesis custom installer
S800. The amplifier should be capable of outputting up to 500 watts per channel with flat frequency response from
20Hz to 500Hz.

Connect your main receiver or processor’
amplifier.

After you have installed the S4SBB back box enclosure as described in the next section, connect the speaker termi­nals on your subwoofer amplifier to the speaker input terminals in the terminal cup located on the top panel of the
back box, making sure to observe the correct polarity.

You will observe two wires hanging down into the opening of the S4SBB enclosure. These are to be connected to the
terminals on the back of the S4S loudspeaker baffle just before installing the S4S in the enclosure. Again, remember
to connect the wires to the correct terminals to maintain polarity. The solid black wire is to be connected to the nega­tive (–) terminal on the baffle, and the solid red wire is to be connected to the positive (+) terminal on the baffle.

You may prefer to use two S4S subwoofer systems in Stereo mode for improved performance and superior imaging,
and to meet THX Ultra2 requirements. Use two mono subwoofer amplifiers, each connected to either the left or right
subwoofer output on your receiver/processor
and right line-level subwoofer outputs on your receiver/processor to the corresponding inputs on your amplifier
connect the positive and negative terminals for each channel to one S4S subwoofer system.

s line-level subwoofer output to the line-level input on your subwoofer

, or use a single two-channel subwoofer amplifier and connect the left

, such as the JBL Synthesis

. Then

Wire Length Recommended Size

Up to 20 ft.
Up to 30 ft.
Greater than 30 ft. 10-gauge

16-gauge
12-gauge

4