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SUPERIOR PERFORMANCE PARAMETERS 

for the new PC units were strategically balanced

so that low resonant frequencies could be achieved along with high sound pressure levels.
Cone mass is held to a minimum for high efficiency yet its Acrylic Resin Laminate 

design yields tremendous rigidity. The lighter the cone the easier it is for the magnet to
move it in and out; therefore, higher sound pressure levels for a given amount of amplifier
power input. Additional loudness is achieved through longer cone travel so we designed
the PC units with 0.25 to 0.35 inches (6-8 mm) of peak-to-peak excursion which is rarely
found in component woofers of this price range.

INCREDIBLY FLEXIBLE INSTALLATION 

is the real benefit to the new Pro Components. The

PC woofers perform well in sealed, vented, and 

 boxes. Due to the low resonance

values, they also work quite well in infinite baffle installations where the woofer is mounted
on the rear deck of a car and uses the trunk for its enclosure.

The best investment in system design is planning time.

Before building a house an architect

completely draws building plans. Although small modifications are often made throughout
construction, 99% of the home is built as planned.

Exactly the same attitude must be

followed in the design of a car audio system and we therefore refer to it as “System
Architecture”.

MULTI-WAY SYSTEMS

Although a simple head-unit with four
speakers will provide reasonable sound, a
really good system almost always requires
some kind of subwoofer. In order to

include the subwoofer speakers a dividing
network must be installed that keeps the
low frequencies out of the midrange
speakers.

“Two-way”  crossovers” have a

crossover point set of 80 to 100 Hz for
example. You 

 crazy with additional

crossover points and amplifiers (three-way,
five-way, etc.) but these should be left to

the better retail installers or high-end

hobbyists.

SUBWOOFER

SOUND QUALITY VS. SPL

A well designed sound system can provide good sound quality and still play loud. Above
about 120 

 (decibels) the sound isn’t perceived as getting much louder due to the 

linearities of the human ear. A loudspeaker with reference value of 90 

 1 watt/l meter

will usually offer about 11 O-l 15 

 inside a car if driven by an amplifier of about 100 watts

(more than enough for most listeners).

Good sound quality is achieved when a system offers several sonic attributes. 

IMAGING 

is

the accurate rendition of instrument placement which can only be achieved with proper

loudspeaker placement. 

STAGING 

is an extension of imaging where a perceived listening

event is recreated with well defined height, width, and depth as with an actual sound
stage. Correct FREQUENCY RESPONSE implies that all frequencies within the range of

human hearing (20-20 

 are audible and balanced in relation to one another. TIMBRE

(pronounced 

 is the system’s ability to reproduce the sound signature of a trumpet

so that it doesn’t sound like a trombone. LINEARITY is the systems ability to provide
consistent frequency response regardless of volume setting. Some systems sound “shrill”
at high levels if the 

 over driven. They may also sound weak at low volumes

due to our psychoacoustic hearing effects which we perceive bass loss at low levels.

Содержание PC105

Страница 1: ...nal Quality Component Subwoofers Subwoofers ti composant de qualitci professionneile woofers cotxomponente de catidad profesiona Subwoofers corn componente de qualidade profissional Made in the U S A Bosch Group ...

Страница 2: ... techniques et conception recommandee des enceintes PC1 25 specifications techniques et conception recommandee des enceintes PC1 55 specifications techniques et conception recommandee des enceintes Blaupunkt demande de soutien technique feuille de fax SUJETS Caracteristiques des nouveaux composants Pro PAGE 10 11 12 13 13 14 15 16 17 17 18 18 28 29 30 31 32 33 34 35 36 Autres notes 37 TEMAS Nuevas...

Страница 3: ... support numbers and addresses with the BLAUPUNKT TECHNICAL SUPPORT SUMMARY SHEET formalizes your tech requests so they can be mailed in and or faxed in to our technical support people Finally in depth TECHNICAL DATA for all PC woofers is provided High performance car audio can be achieved with value conscious components Simply speaking 95 of the car audio subwoofer installations made today really...

Страница 4: ...the subwoofer speakers a dividing network must be installed that keeps the low frequencies out of the midrange speakers Two way crossovers have a crossover point set of 80 to 100 Hz for example You can go crazy with additional crossover points and amplifiers three way five way etc but these should be left to the better retail installers or high end hobbyists SUBWOOFER SOUND QUALITY VS SPL A well d...

Страница 5: ...owering a system can often cause more damage than slightly overpowering it If the speakers are rated for 50 watts rms you can often drive them with a 100 watt power amp without concern IMPEDANCE is the electrical resistance to AC current flow and is typically 4 ohms for most car speakers Impedance loads for a speaker configuration shouldn t fall below 2 4 ohms for most installations to avoid ampli...

Страница 6: ...output of the speaker This wall is absolutely necessary and is referred to as an acoustical baffle It can be accomplished using a box of some kind or simply the rear package shelf of an automobile to isolate the front and back waves of the speaker THIELE SMALL PARAMETERS Every woofer has its own electromechanical characteristics which are called THIELE SMALL parameters The three most important par...

Страница 7: ...oderate efficiencies at low frequencies and the need for large box volumes VENTED boxes extend the low frequency response below that of the sealed box by using a port tube Advantaaes include extended low frequency response lower distortion due to smaller cone movements in its passband good efficiency good transient response moderate size boxes and high power capacity Disadvantaaes include increase...

Страница 8: ...erials to build boxes with thicknesses of 5 8 3 4 I 2 16 mm Solid wood panels should actually be avoided because of vibration potential and wood warping over time All seams in the box should be glued screwed and caulked to prevent wall separation over time due to vibration and environmental changes within the car Cross bracing is important for large boxes to prevent wall vibration Acoustical dampi...

Страница 9: ...tely referencing the formulas and drawings below VOLUME AND AREA CALCULATIONS AREA VOLUME Circle port opening A 0 79 x d x d N A Rectangle A h x w N A Triangle A 0 5xhxw N A Cylinder Port tube N A V 0 79xdxdxh Rectangular box N A V h x w x d Triangular box N A V 0 5xhxwxd Cone N A V 0 26 x d x d x h AREAS 0 d irll c w VOLUMES Speaker parameters and box calculations often need some kind of math con...

Страница 10: ...The following is a list of materials and sources of recommended reading for the person interested in loudspeakers acoustics and electronics Subjective comments are listed accordinnlv DESIGNING BUILDING AND TESTING YOUR OWN SPEAKER SYSTEM David B Weems Copyright 1984 TAB books I 964 Blue Ridge Summit PA 17294 This is an introductory book on designing speakers for the home but is quite applicable to...

Страница 11: ...tions or exclusions may not apply to you This warranty gives you specific legal rights and you may also have other rights which vary from state to state This warranty is void for damage occurring during shipment and for p oducts with defaced serial numbers or date code markings For further information regarding this warranty please contact the Blaupunkt division of the Robert Bosch Corporation 280...

Страница 12: ...5lmm 6 9 Tm 0 59 12OW 240 peak 93 dB 2 83v11m 90 dB lW lm T 0 30 0 mm 4 w 102 mm I Woofer outline drawing FREQUENCY t Hz Anechoic woofer response If you re really tight on space stick with an 8 in this small box Good transient response and power handling c0 5 Below this box volume will put a big bump in the frequency response tie 0 75 Surprising accuracy with good frequency response from a small s...

Страница 13: ... 5m BANDPASS BOX 1 0 vs 1 5 cu rt 110 Im _____________________ ______ m 90 1 0 cu rt 20 50 IDo HZ 2m sm The data above is offered as a starting point for comparison purposes because these designs are only a few of many possible box configurations Be sure to account for the air volume displacement of the woofers and the port tubes NR NOT A RECOMMENDED APPLICATION 29 ...

Страница 14: ...y most listerners should be satisfied __ Somewhat one note performance due to narrow bandwidth response __ _ _ ___ Smooth frequency response good transinents but lower efficiency l Parameter values may deviate slightliin production units but the perceived performance variations will be negligible 3o ...

Страница 15: ...t r e a r tube lube band volume freq box box length length effc y volume volume for 3 for 4 I 0 1 D POfi POfl cubic cubic cubic feet Hz Hz Hz feet feet inches inches dt3 0 75 55 160 95 035 040 3 60 760 91 1 00 45 140 60 0 40 060 5 25 10 3 66 I 25 42 130 77 0 5 0 75 4 20 6 50 69 1 50 37 130 66 0 50 1 00 _ 6 W 11 7 67 _ _ _ _ 1 75 35 130 65 0 5 1 25 6 60 13 1 66 2 00 30 120 60 0 45 1 55 9 50 cNR 65 ...

Страница 16: ...ponse 100 Hz _ 2 0 Smooth frequency response and good transient response ___ SINGLE YEW BANWAS WMJME btkt COMME WT Jill_ _ 3 k _Y 11 i vI ljYLYY y__ _ _ yI Stmfl xX I 1 1 25 A one note sound due to limited bandwidth _ Mwt aCcwa tr 3 5 Wide frequency response but low efficiency Pounder 1 75 Narrow bandwidth acceptable for nearly everyone gg on it Parameter values may deviate slightly in production ...

Страница 17: ...Inches Inches da 0 76 CURD 1 00 56 160 95 0 50 0 50 2 00 4 50 91 1 25 52 140 65 0 65 0 60 1 90 4 25 92 1 50 50 130 76 0 75 0 75 1 90 4 50 92 1 75 42 120 70 0 75 1 M 3 00 6 25 90 3 50 24 105 50 0 75 2 75 6 00 15 1 64 u ft 0 w _ J _ _ _ _ a A_ _ _ _ _ I 20 50 loo IQ 2w 503 The data above is offered as a starting point for comparison purposes because these designs are only a few of many possible box ...

Страница 18: ... s 0 35 ft 9 9 Itr s 132 in2 O O86m 3 1 x 10 M N 4 8 oz 1359 2 0 50 8mm Kapton polymide 1 50 mH 0 25 in 6 4 mm 10 2 Tm 1 13 Woofer outline drawing 8 rl F i i j i ii ii j j _ _ jj ii f rif i ji i j jj Ii jj ii ij i f p I 1 94 dB lW lm 1 Anechoic woofer response SEALED BOX Somewhat boomy sound ___ _ ____ Decent frequency response with excellent transient response _____ Well balanced frequency respon...

Страница 19: ... 62 200 110 090 0 6 0 0 7 5 125 95 2 00 55 150 so 1 10 0 90 0 75 2 25 94 _ 3 50 43 120 70 2 0 1 5 0 75 1 75 94 6 00 25 95 50 2 0 4 0 3 80 6 90 88 V E N T E D B O X 1 5 vs 3 0 CU ftL 110 BANDPASS BOX 3 5 vs 6 0 cu ft 100 I 2 ZOO 5ul The data above is offered as a starting point for comparison purposes because these designs are only a few of many possible box configurations Be sure to account for th...

Страница 20: ... FAX I I 1 What enclosure type do you have or want 1 I sealed 1 1 vented 1 1 bandpass 1 I isobaric I other define 2 What Blaupunkt woofer model numbers are you working with 3 How many woofers are in the same cabinet 4 How many port tubes do you have or want Diameter and length of each 5 Do you want round PVC pipe port tubes or square I round I I square 6 What is the total cubic volume of the enclo...

Страница 21: ... 37 ...

Страница 22: ... Broadview Illinois 60153 Division Blaupunkt de Robert Bosch Inc Mississauga Ontario Canada L5N IRI Copyright 1995 by the Robert Bosch Corporation No portion of this work may be reproduced in any form without the written consent of the Robert Bosch Corporation Printed in the U S A April 1995 PI 147 395 ...

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