Focal 25 A1 Manuel D'utilisation

ACCESS SUBWOOFERS
U s e r
M a n u a l
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.
Cables
For optimum performance the use of OFC cable (Oxygen Free Cable), to a sufficient thickness (2.5mm²)
is highly recommended. This is particularly important in the case of long cable lengths being used in the
installation. We recommend the use of Focal cables FC500 or FC700. Check with your local Focal dealer for
further advice.
Connecting up
Always check the polarity to the subwoofer, and that of the other speakers used in your installation. The polarity
is important to ensure the phase characteristics remain correct, otherwise a "loss" of performance can result.
The spring action input terminals are clearly marked red spot = positive (+) and black spot = negative (-).
These subwoofers can be mounted in the traditional sense with the membrane on view externally, or inverted
mounting with the motor unit and its chrome back plate on display. Inverted mounting helps increasing the
volume for the given space available. When choosing inverted mounting the phase must be inverted (thus swap
the positive / to negative connections) so that the polarity is correctly observed.
Warning
The 30 A1 DB subwoofer uses two voice coils of 4 Ohms each. Please refer to page 3 to connect
this product.
Multi-subwoofer installations
To obtain a more powerful acoustic presence, we recommend the introduction of multiple subwoofers for your
chosen installation. Using multiple subwoofers, various series or parallel or combinations of both can be used,
but always check the specifications of the power source (amplifier) before attempting any installation. It is worth
remembering if low impedance of 2 or even 1 ohm is chosen an amplifier of high quality should always be
used for such installation.
Connections in parallel
Normally the terminal positive (+) on the subwoofer will be connected to the equally marked positive (+) on
the amplifier, and the terminal negative (-) on the subwoofer to the equally marked negative (-) on the amplifier.
Calculation of the impedance is (Z), for the given impedance value nominal (R), is 4 ohms.
• 2 subwoofers : 1/Z = 1/R1 + 1/R2
• 3 subwoofers : 1/Z = 1/R1 + 1/R2 + 1/R3
THE FOCAL GUARANTEE ONLY APPLIES IF PAGE
RETURNED TO US WITHIN
Focal® is a trademark of Focal-JMlab® - BP 374 - 108, rue de l'Avenir - 42353 La Talaudière
cedex - France - Tel. (+33) 04 77 43 57 00 - Fax (+33) 04 77 43 57 04 - www.focal-fr.com
Due to constant technological advances, Focal reserves its right to modify specifications without notice. Images may not conform exactly to specific product.
31
10
DAYS OF PURCHASE
Z= 2 Ω
Z = 1,33 Ω
IS
.
Français page 9