P
OWER
-H
ANDLING
L
IMITATIONS
The power-handling capability of any woofer
is related to both its ability to dissipate heat and
the maximum excursion limits of its cone. Once
the speaker’s voice coil moves outside the mag-
netic gap, power can no longer be converted into
motion and all the amplifier’s power is converted
into heat in the voice coil. This voice-coil heating
is the largest detriment to speaker longevity, so
overexcursion should be avoided. Since speaker-
cone excursion is different for each type of
enclosure, power handling is different for each
enclosure.
Sealed enclosures exert the most control over
the motion of a subwoofer because the air inside
the box acts like a spring against the motion of
the woofer cone. Larger boxes allow for more
excursion, thus providing more low-frequency
output for the amount of power used. When
placed in a sealed box larger than the Vas of the
subwoofer, it will perform as if it were in an
infinite-baffle installation.
Vented and bandpass enclosures have the
lowest amount of excursion for the amount of
sound output. This is a result of port output rein-
forcing the sound output from the woofer. The
mass of the air contained in the port provides an
acoustic load on the woofer’s cone at the tuning
frequency, and this added mass decreases
woofer-cone excursion. Vented boxes do not pro-
vide adequate woofer control when driven below
the port-tuning range, so proper design is impor-
tant. A vented bandpass box will have the lowest
overall cone excursion provided a subsonic filter
is used.
S
PECIFICATIONS
Kappa 80.1w
Configuration:
8" woofer
Nominal Impedance:
4 ohms
Power Handling:
100W rms/400W peak
Sensitivity @ 2.83V/1m: 93dB
Frequency Response:
30Hz – 300Hz
Mounting Depth:
4" (102mm)
Cut-out Diameter:
7-3/16" (183mm)
Kappa 100.1se
Configuration:
10" subwoofer
Nominal Impedance:
4 ohms
Power Handling:
250W rms/1000W peak
Sensitivity @ 2.83V/1m: 93dB
Frequency Response:
25Hz – 250Hz
Mounting Depth:
5-1/16" (129mm)
Cut-out Diameter:
8-7/8" (226mm)
Kappa 120.1se
Configuration:
12" subwoofer
Nominal Impedance:
4 ohms
Power Handling:
300W rms/1200W peak
Sensitivity @ 2.83V/1m: 94dB
Frequency Response:
20Hz – 250Hz
Mounting Depth:
5-13/16" (148mm)
Cut-out Diameter:
10-13/16" (275mm)
Kappa 100.1dvc
Configuration:
10" subwoofer
Nominal Impedance:
4 ohms per voice coil
Power Handling:
250W rms/1000W peak
Sensitivity @ 2.83V/1m: 93dB
Frequency Response:
25Hz – 250Hz
Mounting Depth:
5-1/16" (129mm)
Cut-out Diameter:
8-7/8" (226mm)
Kappa 120.1dvc
Configuration:
12" subwoofer
Nominal Impedance:
4 ohms per voice coil
Power Handling:
250W rms/1000W peak
Sensitivity @ 2.83V/1m: 94dB
Frequency Response:
25Hz – 250Hz
Mounting Depth:
5-13/16" (148mm)
Cut-out Diameter:
10-13/16" (275mm)
•
Voice-coil overheating and burning due to
overexcursion are often caused by overdriving an
amplifier into “clipping.” A severely clipped
signal, or squarewave, contains nearly twice the
power of a clean sine wave at the same level. Bass
that sounds broken up and distorted at higher
volumes is usually indicative of an amplifier that
is clipping and being asked to deliver power
beyond its rated power.
•
Infinite-baffle or “free-air” mounting applica-
tions allow for greater cone excursion than
subwoofers mounted in an enclosure. In order
to compensate, recognize that the power-rating
value of the subwoofer will likely be half its rated
power in this application.
•
Study the excursion curves on the enclosed
Kappa Series data sheet and note the differences
for different enclosure applications. The type and
size of box used will produce different excursion
demands on the enclosed subwoofer and, conse-
quently, different levels of power handling. As
long as recommended parameters are used, the
subwoofer will perform properly in its enclosed
environment. However, any design deviation may
result in less than optimum performance, and
may also subject the subwoofer to overexcursion
(i.e., where the voice coil leaves the gap) that can
eventually damage the speaker. For additional
help with this issue, please contact your autho-
rized Infinity dealer.
Kappa 80.1w OM 7/14/98 10:22 AM Page 3
