Focal BOMBA 20 A1 User manual

Congratulations on choosing Focal automobile vented box. To gain the best
results from your speaker, please ensure you follow these recommendations, and
keep carefully this user manual so that you can consult it later. If not followed
correctly any fault observed may not be covered by the guarantee.
Precautions
For the subwoofer to perform at its best, we recommend to use it in a location where
temperature doesn’t go below 5°C.
• The location must also be dry and offer adequate entilation.
• The supply oltage requirement is 12VDC (13.8VDC) with the negati e connection
grounded. Please make sure that the characteristics of your ehicle correspond with this
requirement before connecting the equipment.
• For safe dri ing, we recommend that you operate your sound equipment at a listening le el
that does not conceal traffic noise.
arning!
The performance of the Focal BombA 20 A1 allows high sound pressure le els to be generated.
We remind you that sustained listening beyond 110dB SPL can permanently and irre ersibly
damage your hearing. We recommend that you adjust the le el of your equipment
correspondingly.
For safety reasons, it is essential that you securely fix the subwoofer enclosure in the boot
(make sure you do not drill through the petrol tank if you fix it with screws).
Mounting kit included:
- 2 x nylon straps
- 4 x metal roll bar
- 8 x fixing screws
- 1 x template
THE FOCAL GUARANTEE ONLY APPLIES IF PAGE 19 IS
RETURNED TO US ITHIN 10 DAYS OF PURCHASE.
BombA 20 A1 User Manual
Français page 9
Due to constant technological advances, Focal reserves its right to modify specifications without notice. Images may not conform exactly to specific product.
Focal-JMlab - BP 374 - 108, rue de l'Avenir - 42353 La Talaudière cedex - France - www.focal-fr.com
Tel. [phone] - Fax [phone]
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Mounting
A power supply kit dedicated to the BombA cabling will shortly be a ailable at your supply.
• Unplug the “+” from the battery
• Make sure you follow the car manufacturer instructions (airbag, alarm system, computer,
immobiliser ...).
• Always use battery lead connections.
Cable routing
The 12V supply cables should be passed down one side of the ehicle and the signal
cables down the other. These cables must be suitably protected to a oid any damage to the
insulation, especially when feeding the cable through from the engine compartment to the
passenger cabin.
Installation
We ha e taken time to design a product that will work exceptionally well. To add to this we
ha e included a fixing kit to ensure the subwoofer remains securely mounted. Please follow
the below mentioned steps to ensure the subwoofer is mounted correctly.
1 - Rear seats must be positioned in their normal fixed position.
2 - Decide the best location possible that suits your automobile and space a ailable. We
recommend the best location for optimum sound quality and most secure is to position
behind the rear seats, in the trunk of the automobile. It can be positioned in either left
centre or right side locations. This will not change the sound quality, as bass frequencies
are not directional.
3 - Ensure the area for subwoofer location is clean and tidy. Any loose objects are remo ed, as
they could knock and damage the subwoofer, and this is not co ered by the warranty.
4 - Once the location has been decided, carefully attach the fixing template with scotch tape
(fig. 1).
5 - Now mark the screw hole positions for the fixing brackets. (Please erify with template).
6 - Drill two holes 2 mm for the 4 fixing brackets, at your defined locations. It is ad isable
that the drill depth be reduced to a minimum length, so to pre ent drilling to deep into the
textile of the seat (fig. 2).
7 - Now carefully position the brackets and one screw per bracket into place (fig. 3).
8 - Now take the two fixing straps and thread through the aperture a ailable on the fixing
bracket (fig. 4) and position the second screw on each bracket.
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9 - Now place the subwoofer into position, lay the straps around the grille. These must be
positioned at the extremity of grille, as indicated on diagram, this ensures the straps do not
interfere with the dri er or port tube. Ensure the straps are flat and untangled (fig. 5).
10 - Attach the straps and pull tight (fig. 6).
11 - Ensure the cabinet is securely fastened into position. Adjust straps if necessary to maintain
a secure hold to the rear seat.
12 - Your subwoofer is ready to use.
Power supply 
(+) The 12V cable (BAT) must be connected to the battery with a cable of appropriate quality
and size, 8mm2 (7AWG). Protect the installation with a 15A fuse on this cable fitted less than
40cm (16”) away from the battery.
(-) The ground wire (GND) must be connected to the chassis of your ehicle with a perfect
electrical connection (remo e some paint to re eal bare metal if necessary) and with a cable
of the same specification as used for the + feed.
Connect the remote cable (REM) to the electrical aerial output or to the remote output of
your radio.
Low level input (RCA) 
Connect to the RCA output of the radio
High-level input 
Connect to the loudspeaker outputs of the radio.
Ne er connect the RCA and the high-le el inputs together.
Adjusting the Volume 
The olume setting allows you to match the le el of the BombA with the le el of the front
system. Setting:
- Turn the gain on the BombA down completely
- Turn the radio up to a normal listening le el.
- Turn the gain  up on the BombA until you get the required balance.
Phase inverter 
It allows you to phase the subwoofer (generally ad ised) or unphase it.
The right setting is determined by listening and finding the one (matching with the front
system) that pro ides the most bass.
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Adjustable cut-off frequency 
An electronic crosso er remo es medium and high frequencies beyond a point set by the user.
The ideal is to extend the bass frequencies in an e en and continuous manner from where the
front system rolls off. In general, a cut-off frequency located between 80 and 100Hz should
be suitable for most systems. This setting becomes more critical when the BombA is used
within a high-end hi-fi system.
The idea cut-off frequency will only be found after extensi e listening to a wide range of
musical.
Warning! Very few recordings possess real bass frequencies. Bass notes such as those found
in Rock, Techno, Ragga music etc. are rarely located within the extreme bass area, but more
likely in the high bass band.
As a consequence, it is recommended to select a cut-off frequency between 100 and 120Hz
for these styles of music. Howe er, you may prefer a lower cut-off frequency for classical
music.
It is possible to set the cut-off frequency anywhere between 50 and 200Hz.
This adjustment should be made in reference to the listening position and with your preferred
type of music.
For a more precise adjustment, your retailer may use an analyzer (RTA).
Dimensions :
5
A = 9-13/16” - 250mm
B = 13-3/8” - 340mm
L = 15-7/16” - 392mm
BombA 20 A1 User Manual
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