THE KIT CONTAINS:
Y
2 pcs conical flanges (1 large & 1 small) in ABS-plastic
Y
1 pc black PVC-tube, made of re-used PVC
Y
1 pc mounting instruction.
DIMENSIONS:
BP-75
BP-110
Tube length
400 mm (16")
400 mm (16")
Inner diameter
69 mm (2,715")
104 mm(4,095")
Outer diameter
75 mm (2,95")
110 mm (4,33")
Inner tube area
37,39 cm
2
84,95 cm
2
(5,79 sq. inch)
(13,16 sq. inch)
CALCULATION OF PORT LENGTH:
If you don´t have a computer calculating program you can use
this formula for calculating the port length:
L = 17914 x d
2
Fc
2
x Vb
17914 = constant
L = port length in cm
d = port inner diameter in cm
Vb = net box volume in liter
Fc = box resonant frequency in Hz
NOTE!
The distance from the port opening inside the box, to the wall
behind it, should be at least 1 - 1,5 times the port diameter in order
not to stop the airflow.
When you test the box with music you should be able to feel the
air-flow from the port. At high volumes with a lot of bass, the air-
flow should increase a lot. If the airflow is low the portlength is
wrong, check your calculation and the speaker data again.
It is important that the box is absolutely air-tight, the air should
come out only through the bass-port.
Thank you for buying a DLS bass-port kit. This kit can be used
together with all types of vented speaker boxes.
In a port with sharp edges a whistling sound may occour at low
frequencies, especially when using small port dimensions. A port
with sharp edges also increases the air flow resistance and could
cause a turbulent air flow. This problem will be minimized when
using DLS conical bass ports.
DLS bass port gives the following advantages:
Y
Minimizes the risk for whistling sounds.
Y
Low loss
Y
Improved dynamics
Y
Easy and good looking mounting
INSTALLATION:
DLS BP-75 and BP-110 can be installed easily, no special
tools are required. All that needs is a round hole of the same
size as the outer ring on the larger flange in the kit. The bass
port can be mounted from the outside if you wish.
The best result is achieved if the bass port is mounted on the
same side as the speaker element. If there is not room
enough to do so, you can mount it on some other side, but the
result may be worse.
DO LIKE THIS:
Calculate the port length, by hand or in a computer program.
Then cut the tube, 22 mm (7/8") for the BP-110 and 20 mm (3/
4") for the BP-75, shorter than the calculated length when
using conical ports in both ends. This is a compensation for
the length of the flanges.
Make a round hole in the box where you want to mount the
bass port.
Mounting hole for BP-75 is 115 mm / 4,53"
Mounting hole for BP-110 is 145 mm / 5,71"
The larger flange should be mounted in the box. Fasten it to
the box with screws or with some glue. There are prepared
drill holes on the back of the flange.
The smaller flange is for the inner end of the tube. Use a
PVC-glue to fasten it on the tube.
Then glue the tube to the port mounted in the box.
Since the inner flange is smaller you can also mount it all
together on the outside, and then mount it into the box
afterwards.
Since the fittingon the details are very good, you can also
mount it together without glue and then make a sound test to
see that everything works alright. When you, after an eventual
readjustment of the port length, are satisfied, you can glue the
pieces together.
Use sealing compound round the flange to make the box as
airtight as possible.
If there is a problem to make room for the larger flange on the
box you can choose to use the smaller one on the outside.
The smaller flange can also be bought separately.
If you have any questions about this product, please contact
DLS customer support center on the telephone number below.
DLS Svenska AB
P.O.Box 13029,
SE-402 51 Göteborg, Sweden
Tel. +46 31 840060
Fax +46 31 844021
E-mail. [email protected]
www.dls.se
DLS BP75 / BP110 Bass port kit
