Sunfire True Subwoofer Signature and Standard Version - Manual (Page 5)

User's Manual
5
Your SunÞ re True Subwoofer EQ is
designed to give you the best possible
low-fre quen cy sound quality for your
Home Theater ex pe ri ence. It in cor po rates
a tre men dous ly powerful built-in am pli Þ er
and a pair of drivers to produce tight,
ß oor-rumbling, denture-rattling bass that
you can feel as well as hear.
The subwoofer is available in two ver-
sions, and this manual covers both:
Signature Edition is a 13 inch cube, with
an output greater than 116 dB peak
SPL, 16 Hz to 100 Hz.
Standard Edition is an 11 inch cube,
with an output greater than 110 dB
peak SPL, 18 Hz to 100 Hz.
The subwoofer has an automatic
equalization system which will tailor the
subwoofer output to compensate for any
room effects. It also has a manual equal-
ization mode.
The subwoofer has an adjustable high
cut Þ lter and a choice of speaker-level
or line-level inputs for easy in cor po ra tion
into existing systems, or as part of a
subwoofer/satellite speaker com bi na tion.
Controls for adjusting the volume,
crossover frequency and phase, allow
the subwoofer to be perfectly matched
to any listening environment and audio
components.
The Drivers
To have lots of bass requires moving
lots of air. Your SunÞ re Subwoofer incor-
porates two drivers that can move back
and forth ap prox i mate ly Þ ve times more
than a normal sub woof er. This gives it a
lot of air moving capacity which allows for
majestic bass per for mance.
Two drivers share the acoustic output.
Sometimes one driver appears to be
moving more than the other. They both
move the same amount only when op-
erating at the limit of their ex cur sion and
power output, or when bass requirements
and music re quire ments demand maxi-
mum output from the system. Otherwise,
the power is shared between the two
drivers in a way that depends on the mo-
mentary am pli tude and the mo men tary
musical spectrum. It is normal for one or
the other to move more or less than its
mate during operation.
The AmpliÞ er
The large movement range of the driv-
ers creates greater air pressure inside
the box than a con ven tion al subwoofer.
There fore, the drive am pli Þ er must be
much more powerful than an or di nary
subwoofer ampliÞ er. In fact, it has to be
so powerful, it is almost hard to believe.
The power ampliÞ er within your SunÞ re
Subwoofer is capable of de liv er ing over
2,700 watts into a 3.3 ohm resistor (the
driver voice coil re sis tance). When the
same full output is applied to the driver,
however, the enor mous back-elec tro -
mo tive force gen er at ed as a con se -
quence of its large motion and giant mag-
net, causes the current ß ow to be much
less than if it were a 3.3 ohm resistor. It
is this singular property of the driver that
allows the subwoofer to be ap prox i mate ly
ten times more efÞ cient than a subwoofer
this size would nor mal ly be.
A compressor circuit kicks in au to mat i-
cal ly if the input signal level reaches a
level that would overload the driver. This
maintains a ceiling on the output without
clip ping. If the input signal is driven even
further, a ‘soft clipping’ circuit is enabled.
This allows the subwoofer to put more
sound into the room to satiate the power
hungry user, but without distortion or
damage to the subwoofer. Thus, for ex-
plosive scenes in movies, this pro duc es
extremely high sound pressure levels
(SPL) in your room without the drivers
banging against the mechanical stops.
For more details of the subwoofer de-
sign, please call us or view our website:
www.sunÞ re.com.
Overview