Genesis Advanced Technologies Speaker S4 8 User Manual

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OwnersManualandSet-upGuide:  
GenesisServoSub4/8  
Contents  
A QUICK START SET-UP GUIDE  
3
SAFETY TIPS  
CONNECTIONS  
PLACEMENT OF THE SUBWOOFER  
ADJUSTING THE CONTROLS  
3
3
4
4
SETTING-UP THE S4/8  
6
POSITIONING AND CONNECTING THE S4/8  
LFE GAIN  
LFE OUTPUT  
POWER  
SPEAKER-LEVEL CONNECTIONS: HIGH LEVEL INPUTS  
LINE-LEVEL CONNECTIONS  
PHASE SWITCH  
6
7
7
8
8
9
9
MAKING YOUR SYSTEM SOUND RIGHT  
10  
THE MAIN CONTROLS  
TUNING THE SYSTEM IN  
LOW BASS  
11  
11  
12  
13  
TUNING FOR LOW FREQUENCY EFFECTS (LFE)  
PLACING AND CONNECTING MULTIPLE SUBWOOFERS  
THE TECHNOLOGY  
13  
16  
THE SERVO ADVANTAGE  
500W CLASS-D SWITCHING AMPLIFIER  
THE TRANSDUCERS  
16  
16  
17  
18  
SPECIFICATIONS  
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AQuickStartSet-upGuide  
Now that you have your new Genesis ServoSub 4/8, we realize that  
you are eager to hook it up and start listening! Nevertheless, please  
read this quick start guide NOW before you begin setting it up.  
Safety Tips  
The S4/8 is a powered subwoofer with a built-in amplifier: it needs to  
be connected to a power socket that is always on. Make sure that you  
are providing the correct voltage, and keep the S4/8 away from water  
and direct heat.  
Connections  
There are two common options for hooking-up the  
S4/8 to your existing system. For dedicated music  
systems and bass extension of satellite speakers,  
we recommend connecting the high-level speaker  
binding posts on the S4/8 to your power  
amplifier’s speaker outputs, or connect them to  
the “speaker through” binding posts on the  
associated speaker, using a short run of cable as  
a jumper.  
Please note that the binding post inputs on the  
S4/8 are high impedance inputs. This means that  
you can connect as many of them as you like to  
the output of a power amplifier, and the amp will  
never “see” the load. This also means that you  
should use an interconnect-type cable to connect  
the S4/8 even if you use the high level inputs.  
Speaker cables are designed for low-impedance  
connections. Hence, unless it is a very short  
jumper, a thin, small interconnect-type cable is a  
better choice than a thick speaker-type cable.  
The second option for connecting the S4/8 to your  
existing system is to hook it up to your preamp out  
using the line level inputs. In this case, if you have  
two outputs on your preamp, use one set for the power amp, and the  
second for the S4/8, avoiding a Y-connector if possible.  
You can use a single S4/8 to augment a pair of speakers, as it  
provides for two high-level inputs.  
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For traditional subwoofer use in audio/video systems in multi-channel  
home theater applications, connect the line level LFE output of your  
processor to the LFE input on the S4/8.  
Our unique LFE Blend™ technology allows you to use the S4/8 in  
BOTH your music system and your home theater system at the same  
time by using the high-level speaker inputs to augment the bass  
response of your satellite speakers and connecting your processor’s  
LFE output to the LFE Input. You are able to blend the two signals  
together for better bass management of your listening room.  
The S4/8’s LFE out can be used to daisy-chain multiple Genesis  
subwoofers together for better control of the bass modes in your  
listening room. This makes bass management easier, and makes for  
tight, fast, articulate bass.  
Placement of the Subwoofer  
One of the most common reasons to buy a subwoofer is to augment  
your existing loudspeakers when they do not provide enough bass for  
your liking. In general, the S4/8 is used to augment front main or center  
speakers in a multi-channel system, and would be placed near the  
center channel or in between two main front speakers.  
In this case, you should also connect the LFE input of the S4/8 to the  
LFE/Subwoofer output of your processor (or daisy-chained from the  
nearest Genesis subwoofer with an LFE output). Since the S4/8 has  
speaker-level inputs for two channels, you can place a single sub  
between the two front speakers of your multi-channel system.  
In a stereo system, you could place the S4/8 in between the left and  
right speaker and connect them to both. In general, it is never  
advisable to have your subwoofers placed symmetrically in a room.  
Hence, we recommend that it be placed nearer the right speaker.  
Adjusting the Controls  
Locate the spec sheet for your existing main L/R loudspeakers or  
center channel, and adjust the Low Pass frequency on the S4/8 so it  
matches the –3dB point of your speaker’s frequency response (If you  
can’t find that the -3dB frequency, set the S4/8 to 63Hz – the 12 o’clock  
position on the knob – and tune by ear from there). For speakers of  
general sensitivity (around 88dB to 93dB), the Bass Gain and LFE  
Gain can also be set at the 12 o’clock position.  
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The Phase switch allows you to reverse the phase of the S4/8. By  
flipping between 0° and 180°, the correct position for this switch will be  
apparent by the greater low frequency output of the system.  
Note: Should your woofer amplifier unexpectedly turn off and you are  
unable to turn it back on, you may have overheated or over-driven the  
amplifier. It can take up to thirty minutes for the amplifier to cool down  
enough to turn back on.  
Be patient. The two most common causes for this are poor ventilation  
and too much amplifier gain (ie, the amp is being driven too hard). If  
the amplifier is well ventilated and it still shuts down then you may have  
the volume control turned up too high. Refer to the section on  
increasing the low frequency response of your speakers without  
turning up the volume control.  
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Setting-uptheS4/8  
While it is relatively easy to add a subwoofer into your system and hear  
more bass, it is not as easy to integrate a subwoofer seamlessly into  
your system. The Genesis ServoSub 4/8 makes system integration far  
easier than most other subs because the servo system makes the  
S4/8’s bass quick, clean and articulate. This means that no matter  
which main speakers you use, the S4/8 will integrate well with them;  
even fast electrostatic or magnetic planar speakers.  
Positioning and connecting the S4/8  
When the S4/8 is used to augment the low-frequency response of a  
loudspeaker, place it as close to it as is practical.  
In typical use, the S4/8 can be used to augment the low-frequency  
response of the Genesis 6.1c center channel. In this case, the G6.1c  
can even be placed on top of the S4/8. Because of the mass-balanced  
design, there is minimal vibration of the S4/8 cabinet caused by the  
woofers.  
When the S4/8 is used to augment a stereo pair of speakers, place it in  
between the two speakers, and not too near the wall. In general, it is  
not advisable to place subwoofers symmetrically in a room. We  
recommend that the S4/8 be placed nearer the right loudspeaker. This  
is because in an orchestra (and also in a jazz band) the bass  
instruments are on the right.  
LFE Input  
The Low Frequency Effects (LFE) input allows the S4/8 to be used for  
augmentation of center or main loudspeakers as well as for the  
reproduction of LFE for your home theater system. The LFE input  
blends the low frequency effects signal from the home theatre  
processor into the normal input signal on the subwoofer. We call this  
our LFE Blend™ technology.  
The LFE input bypasses the internal crossover, and hence uses the  
home theatre processor’s crossover. This means that the S4/8 can be  
used to augment center or front main speakers as well as deliver the  
LFE channel without resorting to digital bass management on the  
processor.  
On the home theatre processor, set the front and center speakers to  
“LARGE” and sub-woofer to “YES”. Then, connect the sub-woofer  
(LFE) line-level output from the processor to either the single-ended  
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RCA or balanced XLR “LFE IN” connector on the S4/8. Do not use  
both of these inputs at the same time.  
We recommend that single-ended interconnects be no longer than 10  
feet (3m). Hence, we have provided balanced LFE inputs. If your  
processor is further than 10 feet from the S4/8, please use a high-  
quality balanced cable.  
If your processor has only single-ended outputs and is further than 10  
feet from the S4/8, we recommend that you consider using an active (or  
passive) signal balancing device to convert the unbalanced output signal  
from your processor to a truly balanced signal. A truly balanced signal  
will give you the benefit of maximum noise rejection and maximum  
signal fidelity over long cable runs.  
The unbalanced interconnect which connects your preamp to the  
balancing device should be shorter than 4.5 feet (1.5 meters). You can  
then use a balanced interconnects to connect the output of the signal-  
balancing device to the input of the S4/8.  
An added benefit of the S4/8 is that the servo-amplifier incorporates an  
active signal-balancing device built in. This means that if your processor  
has only single-ended outputs, but you can place an S4/8 close enough  
to use a single-ended interconnect, then the balanced output of that  
S4/8 can be used to daisy chain to the rest of the system.  
LFE Gain  
The S4/8 has a control for LFEGAIN that is separate from BASS  
GAIN. This allows you to have the S4/8 augment your surround  
speakers as well as deliver LFE around the room at the same time  
without conflicts. The usual way to control the level of the LFE output is  
to set the LFE gain to 6 – the twelve o’clock position – and then use  
the home theatre processor’s level control to dial in the level. However,  
different locations in the room may have different room gain in the bass  
frequencies. The LFE gain control allows you to tune each subwoofer  
for optimum balance.  
LFE Output  
Along with the LFE input, the S4/8 has the unique capability of  
providing an LFE output. This buffered output can be used to daisy-  
chain the LFE signal from the S4/8 to the LFE inputs of other Genesis  
subwoofers including other S4/8’s, S2/12t’s or G928’s. Thus, it is  
possible to channel the LFE signal from your home theatre processor  
to one S4/8, and then from that to another, and another, and another!  
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You can even use BOTH single-ended RCA and balanced XLR LFE  
outputs to daisy-chain even more subwoofers when either the single-  
ended input or the balanced input is used.  
In the case of bass and LFE, using more low frequency sources  
(not higher level) is better than using less. The point is not to  
achieve a higher level of bass response but rather, by using multiple  
subwoofers to distribute the LFE signal around the room, dramatically  
reducing and evening-out room modes and increasing the bass  
capability of the system.  
Distributing low frequency information is also helpful for reproduction of  
Multi-channel Music because you get incredible articulation and detail  
in the bass all around the room.  
Power  
Make sure the ServoSub 4/8 is plugged into a wall outlet that is always  
on. The S4/8 has an auto-on feature and will automatically power up  
from “stand-by” when it detects a signal, and will switch itself to power  
saving after about 10 minutes of being idle.  
We recommend against the use of an  
extension cord for providing AC power.  
If you are forced to use an extension  
cord, make certain that it is as heavy  
duty (a minimum wire thickness of 12  
gauge) an extension cord as you can  
find. The S4/8 running at full tilt can  
draw up to 1200Watts from your power  
supply, so make sure that whatever  
you plug your subwoofer into can  
handle it!  
Speaker-level connections: High  
Level Inputs  
Using a good quality speaker cable,  
connect the output of your power  
amplifier to the binding posts on the  
back of the S4/8. You may also  
connect the S4/8 to the binding posts  
on the back of your loudspeaker  
terminals if this is more convenient.  
Make sure that you maintain proper  
polarity. This means that the plus (+)  
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terminal of your amplifier must be connected to the plus (+/red)  
terminal on the back of the S4/8, and the negative (-) terminal to the  
negative (-/white) terminal.  
Using the high level inputs to feed the S4/8 power amplifier will not  
degrade the sound quality of either your loudspeaker or the subwoofer.  
Line-level connections  
As an alternative, you can use the low-level inputs on the S4/8. Using  
a high quality interconnect cable, connect your preamplifier’s output to  
the low level inputs on the subwoofer labeled PRE AMP IN.  
We strongly recommend that you do not use single-ended  
interconnects longer than 10 feet (3.2 meters) to connect the  
preamplifier outputs to your subwoofer. On many preamplifiers, using  
an interconnect that is too long will negatively affect the performance of  
your preamplifier because of the high capacitance of the interconnect  
cable across the output of your preamplifier. This is why we provide  
balanced inputs on the S4/8. Balanced interconnects can be as long  
as you like.  
If your preamplifier has only one set of balanced outputs and one set of  
unbalanced (RCA) type outputs, choose your first preference of  
connection for the amplifier that is driving your loudspeaker. Use the  
remaining set of outputs to feed the S4/8’s amplifier.  
Do not connect BOTH single-ended and balanced inputs to the S4/8 at  
the same time. You could over-drive the built-in amplifier, and void the  
warranty.  
Phase Switch  
If the subwoofer is out of phase with the speakers they are used to  
augment, there will be some cancellation of the bass frequencies  
where they overlap. Some speakers are designed to be phase  
inverting (in particular those with 2nd order crossovers). There are also  
many power amplifiers that invert the phase of the incoming signal.  
Because there are so many possible combinations, we recommend  
that you flip the switch between 0° and 180°. The correct position will  
be apparent from the greater amount of low-frequency output of your  
system.  
If you have a phase inverting power amplifier and have inverted the  
phase on the subwoofer, AND you are using both line-level and  
speaker-level inputs, you must invert the phase of the speaker-level  
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inputs to the subwoofer. Connect the +ve speaker lead to the –ve input  
terminal, and connect the –ve speaker lead to the +ve input terminal.  
Makingyoursystemsoundright  
The ServoSub 4/8 subwoofer is perfect for use in 2-channel or multi-  
channel music and video applications. The setup for either is very  
similar and the goals should be quite the same too. In our opinion, the  
end goal of adding a high-end subwoofer should be to not “hear” the  
subwoofer work, but rather to add the appropriate amount of low bass  
that is currently missing in your system.  
When listening to music, the full frequency range of the orchestra or  
rock band should be reproduced with proper dynamic range and  
realism, from the lowest notes of a pipe organ to the whack of the  
timpani or the pluck of the lowest string on a Fender bass. When  
listening to film soundtracks, the same goals should be sought after so  
that the results are both realistic and exciting; as the roar of jet planes  
rumble through your living room and prehistoric creatures shake the  
earth!  
Fine-tuning an audio or video system is an art that takes time and  
patience. It can be one of the most rewarding learning experiences you  
will encounter during your pursuit and enjoyment of high-fidelity music  
or video reproduction.  
One of the best pieces of advice we can offer is that you take  
advantage of the ear’s ability to identify similarities in sound. This ability  
is useful in fine-tuning your system because, if every recording you  
listen to (or every video you watch) has a similarity of sound (too much  
or too little of a certain frequency for instance), then you can be fairly  
certain that you have yet to perfect your setup. Keep at it and  
remember to enjoy your music and video as you work on perfecting  
your setup.  
One idea that we would like to suggest is that you set the S4/8’s bass  
gain controls for music, and use your processor to turn it up or down  
for home theater. That way, you have a subwoofer that will take care of  
all your needs.  
With proper setup and placement, you can achieve stunning realism,  
and musically correct and natural bass – not just more bass.  
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The Main Controls  
The S4/8 subwoofer has two controls that you will use to make your  
system (and that includes the room), sound right. The first is the gain  
control of the woofer amplifier. This adjusts the volume at which the  
subwoofer plays.  
The gain can be adjusted from 1 to 11.  
The second control is the low pass filter. This adjusts the crossover  
frequency for the built-in 12dB per octave variable crossover. The  
crossover frequency can be adjusted from 40Hz to 138Hz, where  
frequencies below the number set are sent to the subwoofer, and  
frequencies above are rejected.  
To begin, adjust the low pass filter to 63Hz and set the gain control to 6  
(both at the 12 o’clock position). At this point, you can turn on the  
woofer amplifier.  
Tuning the system in  
Set up your subwoofers one at a time in conjunction with the speaker  
that you are using them to augment. If you are using a single  
subwoofer to augment two different loudspeakers, adjust the  
subwoofer with one speaker at a time.  
Set the low pass filter to the -3dB frequency of your main speakers,  
and the gain control to 6, and start from there. If you don’t know the  
3dB point of your speakers, start working from a low-pass filter  
frequency of 63Hz. This will work for most small speakers.  
We suggest that you start with a single vocal track, with instrumental  
accompaniment, that you are very familiar with. The sound of the  
human voice is more easily recognizable than many instruments and is  
the least complex sound to deal with. Run a mono full-range signal to  
the speaker that you have the S4/8 connected to.  
Turn the gain control of the subwoofer amplifier up or down until the  
voice sounds correct. Concentrate on the mid bass regions (as  
opposed to the very low bass in your recording), to achieve a natural  
blend. The voice and the music accompaniment should sound as if it  
were cut from one cloth, not separate.  
If the voice sounds “thin” or does not have enough “chest” to its sound,  
turn the S4/8’s bass gain control up until it does. You may also want to  
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experiment with increasing or decreasing the low pass filter control.  
This control will raise or lower the frequency cutoff point of the woofer.  
If you find that the sound is “thin” or lacking in mid bass, and that  
turning the gain control up to “thicken” the sound creates too much low  
bass, this is a good indication that you may want to turn the low pass  
filter up to a higher frequency instead. This will extend the response of  
the S4/8 into the upper bass regions without affecting the low bass  
level.  
Next, check the S4/8 using more than just a voice. Select some music  
that you know to have good deep bass, a symphonic piece of music if  
you can, or use a natural bass instrument for your guide. Try to make it  
sound real. You may have to return to the vocal track from time to time  
to make sure you have not gone too far in one direction.  
If, at this point, the overall sound seems to be lacking in mid bass, turn  
the low pass filter to a higher position or, alternately, position the main  
speakers closer together in order to achieve better mid bass coupling  
between the main speakers. If the overall sound is too “fat” turn the low  
pass filter down or adjust the gain. At this point we suggest you use  
only the low pass filter control until you get to the refinement stage.  
Low bass  
If you find that there isn’t enough deep bass in the overall sound of the  
system, your first remedy is the gain control on the S4/8 amplifier. This  
has several limitations. First, turned up too high, it may result in some  
distortion on very low frequencies.  
Secondly, you may make the mid bass produced by the top of the  
woofer out of proportion with the mid bass produced by the bottom-end  
of your main speakers. This would make your system sound “boomy”  
in the mid bass regions.  
A good rule of thumb is to first adjust the gain control of the subwoofer  
for proper mid bass response rather than low bass. The theory is that if  
the mid bass response is correct, then the low bass response should  
be very close to correct.  
A good balance between proper low bass extension and a deep and  
spacious soundstage needs to be established to optimize your new  
speaker’s performance.  
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Tuning for Low Frequency Effects (LFE)  
The LFE input has a separate gain structure and bypasses the  
crossover in the subwoofer. Hence, it should be set-up separately from  
the main speaker augmentation function.  
A simple way to set up the S4/8 for LFE is to use the test and level  
signal available in most home theater processors and multi-channel  
players, and test discs. Many DVD’s include a THX calibration option  
that has a set of test tones for speaker level adjustment.  
Using a high quality sound pressure meter, set the LFE gain so that  
the S4/8 matches the volume of the main speakers.  
If you are using multiple subwoofers, you will need to set each  
subwoofer in turn. As each location of the subwoofer may have  
different bass levels caused by room-related gain, adjust each  
separately. To do this, you first set the LFE gain on all your subwoofers  
to 1 (fully anti-clockwise).  
Then, using a LFE test tone and a sound pressure meter set the LFE  
gain on the first subwoofer to 3dB down (for 3 subwoofers, 5dB down if  
using 5 subwoofers) from the reference volume of the main speakers.  
Write down the setting, and then turn the LFE gain back to zero.  
Go to the next subwoofer and repeat the process until you have the  
LFE GAIN settings of all your subwoofers. When you have all the  
settings, go to each subwoofer and turn up the LFE GAIN to the setting  
you noted down. Re-check the bass volume with all subwoofers on.  
If the bass response is too high or too low, use the subwoofer level  
setting on the processor to match the LFE volume to the volume of the  
rest of the speakers – or do it all again using a higher or lower setting  
for each subwoofer.  
PlacingandConnectingMultipleSubwoofers  
The combination of LFE Blend™ and daisy-chained LFE in all Genesis  
ServoSub™ models means great flexibility. They are all readily suited  
to multiple subwoofer installations when used in a multi-channel music  
or home theater system. One Genesis ServoSub can be used to  
extend the frequency response of any two main speakers, AND at the  
same time deliver the LFE channel.  
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These placement guidelines are only suggestions. Depending on your  
room and the speakers you have, you may want to place them  
differently. Any combination of Genesis subwoofers may be used.  
With one subwoofer, place it in the front of the room between the  
center channel and the right speaker. If your main left/right speakers  
are full-range, and the center channel is not, use the subwoofer to  
augment the center channel as well as to deliver the LFE channel.  
The second subwoofer can be placed in the back of the room. Daisy-  
chain the LFE from the front subwoofer, and use it also to augment the  
two rear (or two surround) channels.  
50%  
50%  
20%  
40%  
40%  
When the third LFE subwoofer is added, place it on one sidewall. If you  
have a 7.1-channel system, use it to also augment the two right  
surround and rear channels, and rewire subwoofer #2 to augment the  
two left surround and rear channels.  
Subwoofer #4 is added to the front left of the room. Once this is done,  
subwoofer#1 can be used to augment the center channel and the right  
channel, and subwoofer #4 to augment the left channel as well as LFE.  
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The final touch will be a fifth subwoofer added into one corner of the  
room. This will excite all room modes equally, so pick any convenient  
corner. In asymmetric rooms, find a corner that makes the system  
sound smoothest. This subwoofer can be used to also augment the  
nearest speaker to make it full-range.  
Notes:  
1. Bass frequencies are not localizable below 60Hz. With a  
wavelength of over 18 feet (6 meters), it is possible to use a  
subwoofer with the low-pass set at 60Hz to augment nearly  
any loudspeaker in a reasonably sized room (longest  
dimension < 18 feet).  
2. The response of any subwoofer (or even the bass response  
of any loudspeaker) is very placement dependent. Whether  
it is placed against a wall, into a corner, or on a pedestal will  
change its response and gain. Hence, it will be necessary to  
tune EACH subwoofer individually before tuning them all  
together.  
3. Each subwoofer in a multi-LFE installation will have a  
different frequency response. Each will excite different room  
modes depending on positioning. Multiple subwoofers will  
more likely smooth out such bass problems, however, while  
theoretically more subwoofers are better, five is really all you  
need in a reasonably sized room.  
4. Sound waves are 3-dimensional. Hence, placing  
subwoofers at differing heights in the room will also help  
even out the bass response of the room.  
For even more information on setting up multiple subwoofers,  
check out the Genesis white paper “Setting up an absolute  
surround distributed bass multi-channel music/movie system”.  
Good luck!  
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TheTechnology  
The Servo Advantage  
Very few loudspeakers use servo drive, either because most designers  
think that it is too difficult to design, too expensive, or because of the  
extraordinary demands a servo system makes on the amplifier and the  
transducer. However, the Chief Scientist of Genesis, Arnie Nudell, first  
introduced the servo system in the legendary Infinity Servo Statik One  
in 1968(!) – so we know how to design and build servo systems.  
The concept of our servo bass system is an easy one to understand: It  
employs an accelerometer as a sensor to constantly monitor the  
movement of the woofer cone, and instantaneously compares it to the  
input signal. This comparison circuit identifies any deviation from the  
ideal and instantaneously applies a corrective signal to compensate for  
the deviation; virtualy eliminating inherent woofer distortion.  
As an example, when you have a high-impact, low-bass signal that  
starts and stops suddenly (for example a kick drum), the inertia of the  
woofer cone causes the cone to be slow to begin moving. Once the  
cone is in motion, the momentum of the cone causes it to keep moving  
- even after the output signal of the amplifier has stopped.  
The sonic result is overhang, bloat, lack of tautness and definition, and  
a blurring of dynamic impact. With the servo system, the circuit senses  
that the woofer is not moving as fast as it should, and applies more  
current to make it move faster. When the signal stops, it detects that  
the woofer is still moving when it shouldn’t, and applies a counter-  
signal to cause the the woofer to stop faster and more effectively than  
normal circuitry would.  
Thus, the servo-drive reduces distortion and improves transient  
response by making the woofer seem mass-less. Typical non-servo  
woofer systems have distortion levels that exceed 10% at even  
moderate levels. The Genesis servo bass system reduces this  
distortion to below one percent at almost any output level. Moreover, it  
drives the woofer to constant acceleration, which makes its frequency  
response nearly flat!  
500W Class-D Switching Amplifier  
The servo system places extraordinary demands on the amplifier  
because it uses enormous amounts of current to make the woofer  
follow the signal. This means that the amplifier used must deliver huge  
amounts of clean power.  
S4/8 Owners Manual Ver 0.1  
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absolute fidelity™  
The best amplifier for this application is a Class-D switching amplifier.  
One of the reasons a Class-D amplifier is optimum for this application  
is that it has a dramatically increased efficiency, especially at lower  
frequencies. A typical Class A/B amplifier is only 50% efficient. A  
Class-D amplifier, on the other hand, can be 90% efficient. A Class-D  
amp also puts out more power with less heat and less power  
consumption; ideal for use as a subwoofer amplifier.  
The S4/8 uses a proprietary, ultra-efficient, discrete MOSFET  
switching amplifier with output capability of up to a full kilowatt. The  
design provides extraordinary control with high-damping and great  
thermal stability, so that you can play the most demanding sources  
continuously at high volume.  
The Transducers  
The transducer used in a servo system must be strong enough to  
withstand the high current approach of the servo, and yet delicate and  
light enough to react extremely quickly. The S4/8 subwoofer features  
four 8-inch woofers that are designed with ribbed aluminum cones, that  
are lightweight and yet inherently stiff. Our aluminum cones exhibit no  
resonance or cone flexure anywhere near the frequencies at which the  
subwoofer operates. The lowest break-up mode (where there can be  
any chance of distortion at all) is at 6,000Hz – far above the 25Hz to  
120Hz frequency response of the S4/8. Therefore, the driver is a  
perfect piston within the frequencies used, and exhibits very low cone-  
breakup distortion.  
S4/8 Owners Manual Ver 0.1  
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absolute fidelity™  
Specifications  
Dimensions:  
24” x 22” x 11 ½ ” (w x h x d)  
(610mm x 559mm x 292mm)  
Frequency Response: 20Hz to 120Hz +/- 1dB  
16Hz to 180Hz -3dB, +2dB  
Weight:  
Inputs:  
87.5 lbs (39.8 kg)  
High-level left and right with 5-way  
binding posts;  
Low-level left and right, single-ended  
RCA and balanced XLR;  
LFE low-level mono single-ended RCA  
and balanced XLR  
Outputs:  
Controls:  
LFE low-level mono buffered single-  
ended RCA and balanced XLR  
Variable low-pass filter  
Variable bass gain control  
Variable LFE gain control  
Phase switch 0º, 180º  
Finish:  
Premium Rosewood  
European Maple  
S4/8 Owners Manual Ver 0.1  
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