VELOCITY VW 250 - Subwoofer BLAUPUNKT - Free user manual and instructions

Brand	BLAUPUNKT
Model	VELOCITY VW 250
Product type	Subwoofer
Manual languages	FR, DE, EN, ES, IT, NL, PT
Supported enclosure types	Infinite baffle, sealed enclosure, bass-reflex, single-vent bandpass, double-vent bandpass
Recommended enclosure material	MDF or birch plywood boards 19 to 25 mm thick
Minimum cable cross-section	4 mm²
Recommended bass-reflex port diameter	10 to 15 cm
Resonance reduction	Sheep wool or polyester felt (5-10 cm) on 50% of inner walls
Sealing	Glue, screw, and seal all walls
Reinforcement	Reinforcement ribs for large dimensions
Isobaric configuration	Possible: two woofers in a sealed volume reduced by 50%
Power (not specified)	Consult authorized dealer
Impedance (not specified)	Consult authorized dealer
Power supply	Vehicle battery (12V)
Recommended installation	By an authorized Blaupunkt dealer
Safety instructions	Disconnect battery before installation; watch out for airbags, alarms, onboard computer
Manufacturer warranty	European Union (see conditions at www.blaupunkt.de)
Recycling	Recyclable product, separate waste collection
Customer service	Blaupunkt GmbH, Hotline, Robert-Bosch-Str. 200, 31139 Hildesheim, Germany

Frequently Asked Questions - VELOCITY VW 250 BLAUPUNKT

Which type of enclosure to choose for my subwoofer?

The choice depends on your priorities: sealed enclosure for good impulse response and power handling, bass-reflex for deeper bass, or bandpass for high efficiency in a narrow band. Consult the manual for the advantages and disadvantages of each type.

How to install the subwoofer without damaging the vehicle?

Before any installation, disconnect the negative battery terminal. Follow the manufacturer's safety instructions (airbag, alarm, onboard computer). Avoid drilling near cables, batteries, or fuse boxes. Mount the subwoofer on a solid surface, never on a flexible rear shelf.

What cable cross-section to use between the amplifier and subwoofer?

Use a cable of at least 4 mm² cross-section and as short as possible to minimize losses and ensure good transmission.

Can I build the enclosure myself?

Yes, with MDF or plywood boards 19 to 25 mm thick. Ensure the enclosure is perfectly sealed and stable. Glue, screw, and seal all joints. Add reinforcement ribs for large dimensions.

How to reduce parasitic resonances in the enclosure?

Cover at least 50% of the inner walls with a damping material such as sheep wool or polyester felt 5 to 10 cm thick. This also increases the effective volume by 10 to 20%.

What is an isobaric configuration?

It involves placing two woofers facing each other in a common sealed volume. This reduces the required volume by half but decreases efficiency by about 3 dB. The amplifier power must be adjusted accordingly.

What bass-reflex port diameter do you recommend?

A diameter of 10 to 15 cm is recommended to avoid air noise. Use commercially available PVC tubes, with elbow connectors if necessary.

Where to find detailed technical specifications?

Consult the Blaupunkt website at http://www.blaupunkt.com. You will find specifications, instructions, and an enclosure simulator.

How to maintain my subwoofer?

Clean the exterior surface with a soft dry cloth. Avoid chemical products. Regularly check connections and cable condition. In case of problem, consult an authorized dealer.

What to do at the end of the product's life?

Do not dispose of the appliance with household waste. It is made from recyclable materials. Use local collection and recycling programs.

USER MANUAL VELOCITY VW 250 BLAUPUNKT

Congratulations on your purchase of your new Blaupunkt Velocity-Series subwoofers. We have invested tremendous effort in the design process of the new Blaupunkt Velocity-Series subwoofers, in order to achieve superior musical performance.

For maximum performance and reliability, we highly recommend that your new Blaupunkt Velocity-Series subwoofers be installed by an authorized Blaupunkt dealer. By using our Blaupunkt Velocity-Series component speakers and amplifiers, you can be assured of making the best out of your high-quality audio hi-fi system without spoiling the sound by using components of inferior quality.

For additional information on the Blaupunkt product line (technical data, user notes, and soon also a simulation program for subwoofer housings), visit our Internet site at: http://www.blaupunkt.com

We provide a manufacturer guarantee for our products bought within the European Union. You can view the guarantee conditions at www.blaupunkt.de or ask for them directly at:

Blaupunkt GmbH

Hotline

Robert-Bosch-Str. 200

31139 Hildesheim

Germany

Safety precautions

Before starting to mount your speakers, please read carefully the instructions on installation and connection.

Disconnect the negative terminal of the battery before carrying out installation and connection work. Observe the vehicle manufacturer's safety instructions (regarding airbags, alarm systems, trip computers, vehicle immobilizers).

When drilling holes, take care to avoid damage to vehicle components (battery, cables, fuse boxes). Do not mount the subwoofer onto flexible rear decks (hatchback vehicles) or anywhere where they may fall forward.

SUBWOOFER ENCLOSURE TYPES

Sound is created by the movement of the woofer cone back and forth. If a woofer cone moves forward creating a positive pressure wave, this same motion creates a negative pressure at the back of the woofer. If these two waves combine due to the lack of a wall separating the front of the speaker sound from the back, the output from the woofer is effectively cancelled, thus substantially reducing the bass 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.

COMMON ENCLOSURE TYPES

In the car audio world, there are five types of subwoofer enclosures commonly used: infinite baffle, sealed box (closed box), vented box (bass reflex), single-vented bandpass (often incorrectly referred to as "5th" order), and dual-vented bandpass (often incorrectly referred to as "7th" order). No single design is superior because each has its own compromise in performance, power handling, and design complexity. The bandpass name implies a "built-in" acoustical response which has a natural highpass response (30 Hz for example) but also a lowpass response suppressing high frequencies (e.g., > 80 Hz).

INFINITE BAFFLE (fig. a) designs simply use the trunk of the car for its acoustical enclosure and the rear deck to isolate the front and rear sound paths. Advantages include simple installation and adequate performance for most systems. Disadvantages include poor power handling capacity and substandard transient response.

SEALED boxes (fig. b) offer one of the best compromises in power handling and performance. Because of the "air spring" provided by the box, the advantages include simple box construction, higher power handling, excellent transient response, and smooth low frequency rolloff. Disadvantages include only moderate efficiencies at low frequencies and the need for large box volumes.

VENTED boxes (fig. c) extend the low frequency response below that of the sealed box by using a port tube. Advantages include extended low frequency response, lower distortion due to smaller cone movements in its passband, good efficiency, good transient response, moderate size boxes, and higher power capacity. Disadvantages include increased complexity in box design and possible woofer damage due to over-excursion of the woofer cone below the cut-off frequency of the vented box.

SINGLE-VENTED BANDPASS boxes (fig. d) are relatively new (about 5 years in the car) but offer some advantages of both the sealed and vented designs. Advantages include reasonable efficiency, small box volumes, good transient response, extended low frequency performance, and can be used with very high power amplifiers. Disadvantages include slightly lower efficiency compared to a vented box and increased complexity in box design and construction.

DUAL-VENTED BANDPASS boxes (fig. e) vent the sound from the front and back of the woofer through individually tuned enclosures on the front and rear of the woofer. The advantage of this design is its high efficiency over a narrow frequency band. Disadvantages include complex design and construction, large box volumes, poor transient response, and susceptibility to cone over-excursions (damage) for sound outside its primary frequency band.

ISOBARIC WOOFER CONFIGURATIONS

Increasing in popularity in recent years is the compound woofer design, more commonly known as the "Isobaric" design. Isobaric actually means "constant pressure" which is the case having two woofers moving an encapsulated pocket of air between them in the same direction.

This arrangement acts like a single speaker which effectively reduces the required box volumes for a subwoofer system by 50%, which is substantial if you are space-limited. Unfortunately, the trade-off for space is the 3 dB loss in efficiency, but this is usually recovered with increased amplifier power. Care must be taken to avoid air leaks between the two woofers, and final speaker wiring and impedance loads must be carefully watched.

ISOBARIC CONFIGURATION (TANDEM)

SUBWOOFER ENCLOSURE CONSTRUCTION

Before starting final box assembly, some basic construction issues should be mentioned:

• Infinite baffle construction in a car is done by simply cutting a piece of wood which will act as an acoustical divider isolating the front and rear sound of the woofer. This piece of wood is mounted inside the trunk of the car under the rear deck, or against the back of the rear seat, and should have some kind of caulking to seal off all residual air leaks.
• Box construction can take on nearly any shape since we are dealing with low frequencies. Odd shapes that are difficult to cut and glue should be avoided.
• Particle board, MDF, or high grade birch plywood are good materials to build boxes of thicknesses of 19 to 25 mm.
• 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 damping material (sheep wool or fiberglass batting 5 to 10 cm thick), attached to 50% or more of the interior walls, helps reduce box noise and also increases the box volume seen by the woofer by 10-20%. The application of self-adhesive damping mats to the inside walls also helps to eliminate wall resonances.
• The cables running from the amplifier to the subwoofer should be as short as possible with a cable cross section of at least 4 mm2.
• The final box should be rock solid and air tight but should also remain serviceable should a woofer be damaged for any reason.
• When possible, use 10 to 15 cm diameter port tubes to avoid wind noise from smaller diameter sizes. PVC plumbing pipe in various diameters is available at most hardware stores with "elbow" pipes allowing you to bend the tubes inside the box.
• Try to always use active (electronic) crossovers, such as those built into our Velocity amps, for example.

TYPES OF SUBWOOFER BOXES

BUILDING A SUBWOOFER BOX

TYPES OF SUBWOOFER BOXES

In the CarAudio area, five different subwoofer enclosures are mainly used: INFINITE BAFFLE SPEAKERS, SEALED ENCLOSURES, BASS REFLEX ENCLOSURES, VENTED BANDPASS ENCLOSURES (often incorrectly called "5th order enclosures") and DOUBLE VENTED BANDPASS ENCLOSURES (often incorrectly called "7th order

SUBWOOFER ENCLOSURE CONSTRUCTION

Recycling and disposal

Our products are made from materials that can be disposed of in an environmentally sensitive manner and are suitable for appropriate recycling. Products that are to be scrapped must be collected separately from household waste. To dispose of the product, please use the available waste return and collection systems.

GERMAN

10" SUBWOOFER • TECHNICAL DATA
Nominal diameter	10.0 in (250 mm)
Nominal impedance	2x2 Ω
DC resistance (Re)	2x1.8 Ω
Resonance frequency (fs)	42 Hz
Frequency Response	35-1000 Hz
Total Q factor (Qts)	0.63
Mechanical Q (Qms)	8.48
Electrical Q (Qes)	0.68
Equivalent air volume (Vas)	11.3 ltr's
Effective cone area (Sd)	41.5 in² (0,027 m²)
Voice coil diameter	70 mm
Voice coil former material	Aluminium
Linear excursion (Xmax)	±15 mm
Continuous power (Pe)	500 W (1500 peak)
Sensitivity (SPL)	92 dB

Vw 250

Recommended box designs • Boxenempfehlung • Conception recommandée des enceintes • Box raccomandati • Aanbevolen boxer • Rekommendationer • Recomendaciones de cajas de altavoz • Caixas recomendadas • Anbefaling af bokse

Sealed:	no recommendation
Vented:	30 liters 2x Port: D = 10 cm, L = 55 cm rounded on both sides Fb = 35 Hz, F3 = 29 Hz
Bandpass:	no recommendation

Vw 250

Recommended box designs • Boxenempfehlung • Conception recommandée des enceintes • Box raccomandati • Aanbevolen boxer • Rekommendationer • Recomendaciones de cajas de altavoz • Caixas recomendadas • Anbefaling af bokse

Vented:

Vw 300

Specifications • Technische Daten • Caracteristiques techniques • Specifiche • Specificaties • Specifikationer • Especificaciones • Especificações • Specifikationer

12" SUBWOOFER • TECHNICAL DATA
Nominal diameter	12.0 in (300 mm)
Nominal impedance	2x2 Ω
DC resistance (Re)	2x1.8 Ω
Resonance frequency (fs)	37 Hz
Frequency Response	30-1000 Hz
Total Q factor (Qts)	0.69
Mechanical Q (Qms)	9.3
Electrical Q (Qes)	0.74
Equivalent air volume (Vas)	30.4 ltr's
Effective cone area (Sd)	73 in² (0.051 m²)
Voice coil diameter	70 mm
Voice coil former material	Aluminium
Linear excursion (Xmax)	±15 mm
Continuous power (Pe)	750 W (2.250 peak)
Sensitivity (SPL)	93 dB

Vw 300

Recommended box designs

Sealed:	40 liters, F3 = 46 Hz
Vented:	70 liters 2x Port: D = 10 cm, L = 30 cm rounded on both sides Fb = 30 Hz, F3 = 25 Hz
Bandpass:	no recommendation

Vw 300

Recommended box designs

Sealed:

Vented:

Vw 380

Specifications

15" SUBWOOFER • TECHNICAL DATA
Nominal diameter	15.0 in (380 mm)
Nominal impedance	2x2 Ω
DC resistance (Re)	2x1.8 Ω
Resonance frequency (fs)	36 Hz
Frequency Response	25-1000 Hz
Total Q factor (Qts)	0.83
Mechanical Q (Qms)	8.36
Electrical Q (Qes)	0.92
Equivalent air volume (Vas)	44 ltr's
Effective cone area (Sd)	113 in² (0,073m²)
Voice coil diameter	80 mm
Voice coil former material	Aluminium
Linear excursion (Xmax)	±15 mm
Continuous power (Pe)	1500 W (3.000 peak)
Sensitivity (SPL)	94 dB

Vw 380

Recommended box designs

Sealed:	100 liters, F3 = 37.4 Hz
Vented:	100 liters 2x Port: D = 15 cm, L = 48 cm rounded on both sides
Bandpass:	no recommendation

Vw 380

Recommended box designs

Sealed:

Vented:

Subject to changes!

Service numbers

Country:		Phone:	Fax:	WWW:
Germany	(D)	0180-5000225	05121-49 4002	http://www.blaupunkt.com
Austria	(A)	01-610 39 0	01-610 39 391
Belgium	(B)	02-525 5444	02-525 5263
Denmark	(DK)	44 898 360	44-898 644
Finland	(FIN)	09-435 991	09-435 99236
France	(F)	01-4010 7007	01-4010 7320
Great Britain	(GB)	01-89583 8880	01-89583 8394
Greece	(GR)	210 94 27 337	210 94 12 711
Ireland	(IRL)	01-4149400	01-4598830
Italy	(I)	02-369 62331	02-369 62464
Luxembourg	(L)	40 4078	40 2085
Netherlands	(NL)	023-565 6348	023-565 6331
Norway	(N)	66-817 000	66-817 157
Portugal	(P)	01-2185 00144	01-2185 11111
Spain	(E)	902 52 77 70	902 52 77 70
Sweden	(S)	08-7501500	08-7501810
Switzerland	(CH)	01-8471644	01-8471650
Czech. Rep.	(CZ)	02-6130 0441	02-6130 0514
Hungary	(H)	01-333 9575	01-324 8756
Poland	(PL)	0800-118922	022-8771260
Turkey	(TR)	0212-335 06 69	0212-346 00 40
USA	(USA)	800-2662528	708-6817188
Brasil(Mercosur)	(BR)	[phone]	[phone]
Malaysia(Asia Pacific)	(MAL)	[phone]	[phone]