Infinity 120.1SE Speaker System User Manual


 
WARNING: Playing loud music in an automotive
environment can permanently damage your hear-
ing, as well as hinder your ability to hear traffic.
The maximum volume levels achievable with
Infinity speakers, combined with high power
amplification, may exceed safe levels for extended
listening. We recommend using low volume levels
when driving. Infinity accepts no liability for hear-
ing loss, bodily injury, or property damage as a
result of use or misuse of this product.
A FEW WORDS ABOUT ENCLOSURES
Your Kappa Series subwoofer requires an
enclosure to realize its full low-frequency
response. The speaker’s design is flexible enough
to produce exceptional results whether you speci-
fy a small sealed, vented or bandpass enclosure.
In vented and bandpass enclosures, box size and
port-tuning frequency will also help dictate the
low-frequency performance and output capability
of your system.
Your Kappa Series subwoofer will also work in
infinite-baffle applications where there is no space
or budget to build a box. Be aware that infinite-
baffle or “free-air” mounting will reduce the
power handling of any subwoofer compared to
an application using an enclosure.
Finally, any deviation from recommended
enclosure volumes or port dimensions should be
made using dedicated enclosure-design software.
If this type of software is not available to you, ask
your authorized Infinity dealer for help.
box. Rectangular vents can be used as long as
the cross-section surface area matches the
recommended port-area values in the enclosed
data sheet.
5. When using vented boxes, we recommend
using a subsonic filter (like the DBO feature found
on Kappa Series power amplifiers) to limit the
power sent to the speaker at frequencies below
the enclosure’s port-tuning frequency,
thus limiting the speaker’s excursion.
Use the recommended box designs on the
enclosed data sheet. Choose cabinet dimensions
to fit your vehicle, but do not change the enclo-
sure’s volume. Doing so will change the tuning
frequency of the enclosure and may adversely
affect final performance. If you cannot perform
the necessary calculations yourself, please con-
tact your authorized Infinity dealer for help.
In addition, there are a number of points
you’ll want to keep in mind as you construct an
enclosure:
1. Use 3/4" (19 mm) MDF (medium-density fiber-
board) or marine birch wood to build an enclo-
sure. Enclosures for 12" and larger subwoofers,
or small subwoofers driven by high-power ampli-
fiers, should be constructed using 1" (26mm)
material.
2. Seal all joints with glue and screws; do not
use nails. We recommend “deck,” “zip” or drywall
screws since they have coarse threads for better
grip and don’t require pre-drilling holes. Once the
box has been tested, seal all interior joints with
silicone caulk.
3. Depending on the application, fill the enclosure
according to the design you have chosen from
the enclosed data sheet in one of three ways:
zero-percent fill (i.e., no fill), 50-percent fill (i.e.,
1"-thick polyfill sheets on all inside walls except
where subwoofer is mounted), or 100-percent fill
(i.e., entire box is stuffed with loosely packed
polyester fiberfill).
4. Use PVC or ABS pipe for ports. Keep in mind
that the openings at either end of the port must
be at least one port diameter away from any
obstructions, including filling material inside the
YOUR CAR AND BASS REPRODUCTION
Depending on the size of the vehicle’s interior
listening space, reproduced bass frequencies
below 80Hz are boosted by nearly 12dB per
octave in the car as frequency decreases. NOTE:
This effect, known as the vehicle’s transfer func-
tion, plays an important part in shaping the over-
all in-car response and is displayed graphically
along with freespace response on the enclosed
data sheet for your Kappa subwoofer.
ENCLOSURE CALCULATIONS AND BUILDING BOXES
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