Blaupunkt ProComponent PCw 1000 Owner'S Manual Download Page 9

– 

10

AREA AND VOLUME CALCULATIONS

Although many enclosures can now be purchased in prefabricated form, building your own enclosure is often fun,
acoustically rewarding, or even a necessity to properly fit many vehicles.  In order to build such a box there MUST be a
basic understanding of mathematic principals or you will wind up wasting incredible amounts of time and money by
making mistakes in the box design and assembly.

B

ASIC

M

ATHEMATICS FOR

E

NCLOSURE

C

ONSTRUCTION

The areas of surfaces
or openings are
calculated in square
inches (in2).  Such
calculations depend
upon height and width
values or diameters for
circles

d

w

h

w

h

AREAS

circle or a hole

rectangular wall or area

triangle wall or area

AREA CALCULATIONS

Circle or hole 

Area = 0.79 x d x d

Rectangular wall or area 

Area = h x w

Triangle wall or area 

Area = 0.5 x h x w

The volumes of
assemble shapes are
measured in cubic
inches (in3).  Such
calculations depend
upon height, width, and
depth calculations for
rectangular shapes and
a diameter and height
for a tube shape.

AREA AND VOLUME CONVERSIONS

Technical data for speakers are often given in English and Metric unit values (e.g., inches and meters).   Also, when
calculating dimensions we must often flip between size formats (e.g., cubic inches and cubic feet).  To easily convert
back and forth between two formats you can use the conversion table below.

h

d

h

d

d

w

h

h

d

VOLUMES

tube shape

rectangular shape

triangular/wedge shape

cone shape

d

VOLUME CALCULATIONS

Cylinder (port tube) 

Volume = 0.79 x d x d x h

Rectangular box 

Volume = h x w x d

Triangular box 

Volume = 0.5 x h x w x d

Cone shape 

Volume = 0.26 x d x d x h

VOLUME AND AREA CONVERSIONS

TO CONVERT YOUR NUMBER FROM:

MULTIPLY YOUR NUMBER BY:

TO GET A NEW VALUE IN

Inches

0.0254

Meters

Meters

39.37

Inches

Square inches

0.007

Square feet

Square feet

144

Square inches

Cubic inches

0.00058

Cubic feet

Cubic feet

1728

Cubic inches

Liters

0.035

Cubic feet

Cubic feet

28.3

Liters

Summary of Contents for ProComponent PCw 1000

Page 1: ......

Page 2: ...s 7 Subwoofer enclosure types 8 Active passive electrical configurations 9 Basic mathematics for enclosure construction 10 Sample boxes 11 Final subwoofer enclosure construction 12 Additional referenc...

Page 3: ...gh listening levels Below is a good summary comparing old cones with the new technologies In addition to the TPC cones is the expansion of our extended pole program The extended pole piece of the subw...

Page 4: ...and speaker wires are routed away from high current power lines for audio amplifiers and vehicle systems lines when possible This will help prevent noises from creeping into the audio system plus prev...

Page 5: ...y improper installation on uneven surfaces This can occur when surfaces are heavily padded or carpeted and the screws are unevenly tightened or over tightened The results will be a damaged voice coil...

Page 6: ...viding network must be installed that keeps the low frequencies out of the midrange speakers Such a crossover network directs the higher and lower frequencies to their respective drivers Such a crosso...

Page 7: ...se and smooth low frequency roll off Disadvantages moderate to large box sizes moderate efficiency moderate sound pressure levels VENTED BOX a k a Ported Box and Bass Reflex is simply a sealed box but...

Page 8: ...e to its small size and better frequency contouring But it must be placed in front of the amplifier and process the signals via the RCA cables This is rarely a problem in most installations The passiv...

Page 9: ...asured in cubic inches in3 Such calculations depend upon height width and depth calculations for rectangular shapes and a diameter and height for a tube shape AREA AND VOLUME CONVERSIONS Technical dat...

Page 10: ...rform well All dimensions are stated for exterior sizes and are calculated with compensations for box wall thickness using 3 4 wood Also each volume is adjusted for air volume displacements for a woof...

Page 11: ...icated boxes often work well even if off a little bit Also if you do forget to compensate for woofer and port tube volume displacement it is rarely acoustically noticed by most people Very low frequen...

Page 12: ...actor BL 11 65 Tm Effective cone area Sd 339 sq cm Compliance Cms 413 uM N Moving mass Mms 72 g COMMON BOX DESIGNS SEALED CU FT COMMENTS Small box 0 4 11 3L Limited deep bass but O K for many listener...

Page 13: ...4cm 9 0 22 9cm 89 Port Length w 2 dia port in cm Port Length w 3 dia port in cm SPL dB ref 1W SINGLE VENTED BAND PASS BOX Vt Volume Total cu ft L f3 low Hz f3 hi Hz 0 6 17 0L 50 150 0 3 8 5L 0 3 8 5L...

Page 14: ...factor BL 12 25 Tm Effective cone area Sd 514 sq cm Compliance Cms 397 uM N Moving mass Mms 105 g COMMON BOX DESIGNS SEALED CU FT COMMENTS Small box 0 5 14 1L Limited deep bass but O K for many listen...

Page 15: ...m 8 5 21 5 90 Port Length w 2 dia port in cm Port Length w 3 dia port in cm SPL dB ref 1W SINGLE VENTED BAND PASS BOX Vt Volume Total cu ft L f3 low Hz f3 hi Hz 1 0 28 3L 37 156 0 60 17 0L 0 40 11 3L...

Page 16: ...her such claim is in contract or tort No attempt to alter modify or amend this warranty shall be effective unless authorized in writing by an officer of Robert Bosch Corporation THIS WARRANTY IS IN LI...

Page 17: ...Voor onze producten die binnen de Europese Unie zijn gekocht bieden wij een fabrieksgarantie U kunt de garantievoorwaarden oproepen op www blaupunkt de of direct opvragen bij Blaupunkt GmbH Hotline C...

Page 18: ...82 Purchase Date Retailer Address City State Zip Telephone Installer Vehicle PURCHASE INFORMATION OTHER NOTES...

Page 19: ...83 NOTES...

Page 20: ...ration BLAUPUNKT is a registered trademark owned by Blaupunkt GmbH Printed in China MARCH 2003 North South America Robert Bosch Corporation Sales Group Mobile Communications Division 2800 S 25th Avenu...

Reviews: