Specifications

DLS-BOX COMPUTER PROGRAM
Most boxes should be damped inside with syntetic
(acoustic) wool (do not use any rockwool types).
Attach the damping material on the wall opposite from
the speaker and port. A sealed box should be filled
up to 70-100% with acoustic wool.
In a vented box the speaker and port should be
mounted on the same side, otherwise a fade-out of
some frequencies can occour. In most car-types,
except for SEDAN cars, the speaker and port should
be directed backwards for best result.
If you plan not to cover your box with felth cloth or
imitation leather you should also tighten behind the
speaker element before mounting it in the box. It must
be absolutely air-tigth.
If you build an isobaric-box use through screws with
nuts and washers to fasten the speakers. Also tighten
the screw holes with sealing compound. Be sure to
connect the isobaric speaker pair in the correct way.
You can´t use felt cloth or similar in front of the ports,
especially in band-pass boxes.
Good luck with your box project!
SOME ADVICES FROM DR. "BACKE"
When building a bass box the following are very
important:
The box must be very steady and completely air-
tight. Use 22 mm particle board or 19 mm MDF-
board. The particle board has a self resonant
frequency of 14 Hz while the MDF has a resonant
frequency of approx. 400 Hz. Its important to stabilize
the box inside with some braces, especially the boxes
made of MDF could cause "PLONK"-sounds if it´s
not sufficiently braced.
If you are using a milling machine its better to use
MDF-board since particle board wears the cutter
edge. After cutting all pieces to the box you attach
glue in all joints and screws every 10 cm. Use more
screws if the edge cutting isn´t perfect.
The length of the screws should be a little more than
double the board thickness. Tighten all joints with
extra silicon sealing compound.
If you build a bandpass box let one side be removable
to make it easier to change speaker.
Use sealing strips in the joint. The length of the screws
should be 3 times the board thickness. Mount them
6 cm apart.
Use conical bass ports for best result. (DLS BP-75
or BP-110).
If the ports are too long for the box you can add a
bend to it. Either cut the tube and glue it together in
angle, or use factory made tube bends.
It´s easier to use the factory made ones. The total
length must be the same as for a straight tube. Make
the measure in the center of the tube.
The port opening inside the box must not be closer
to a box wall than the ports own diameter. Otherwise
it will have negative effects on the airflow.
BOX EXAMPLES
On the following pages you will find examples on
suitable boxes for DLS speakers and subwoofers.
If you follow the advices in this handbook we are
sure you achieve a good car sound.
Good luck !
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If you have any questions you are always welcome
to call us on DLS in Sweden. We will do our best to
assist you.
Telephone: [phone]
Fax: [phone]
E-mail: [e-mail]
Download the DLS-BOX 2000 from our WEB-site
www.dls.se or www.audiophiles.nu
DLS SOUND HANDBOOK - SPEAKER BOXES
A speaker box can be calculated either by hand or
with the help of a computer program. DLS-BOX 2000
is a program that easily helps you design your own
box to your DLS speakers.
You choose speaker, box type, car-type and music
type and the program calculates the correct box
volume. The program is developed in cooperation with
Backes ljudbyggeri in Ekerö. "Dr. Backe" has many
years of box building experince and assures you that
if only the parameters are correct the program will
give you the best speaker box.
Read his box building advices below.