Supplying Power to the GTi Amplifier, Over

SUPPLYING POWER TO THE GTi AMPLIFIER

POWER IN IS	HOW YOUR CHARGING	PROGRAM MATERIAL
POWER OUT	SYSTEM WORKS	AND CURRENT DEMAND

Few stock batteries can provide the current required to reproduce even

In order to get full power out of your amplifier, you must provide full power to your amplifier. That’s a basic rule of physics. The A6000GTi amplifier can draw nearly 800 amperes when reproducing sine waves at full output. Both JBL A6000GTi and A3000GTi amplifiers can quickly exhaust the factory-installed charging system of any vehicle on the road today. With this much available amplifier power, you will need to beef up your vehicle’s electrical system to satisfy the amplifier’s current demands. We recommend adding at least two 12-volt batteries, connected in parallel with cold-cranking capacities of at least 600 amperes each, to the factory-installed charging system.

The battery’s job is to start your vehicle. Running the electrical accessories is the alternator’s job. The battery isn’t designed to be a continuous source of power. It is a renewable source and is charged by the alternator when the engine runs. Battery charging can only occur when the current demand from the electrical accessories is less than the total cur- rent output capacity of the alternator.

Music is a combination of loud and soft sounds, with varying durations and rhythms that present unique current demands during amplification. For example, it may take full power

to reproduce the sound of a kick drum. The peak power demand doesn’t last very long, but it is repeated over

and over.

If your charging system can’t provide all the power your amplifier needs on a continuous basis, it still may be adequate. During the sound of the kick drum, the battery can provide the extra current that’s necessary, and between kick drum beats, the alternator will put some of the energy back into the battery.

However, depending on the current rating of the alternator, the amplifier’s maximum output power, the music content, and the charging system’s capability, the alternator may not be able to keep up over time. In that case, you’ll need to install a somewhat larger alternator for more current, or adjust your driving and listening habits, to give the alternator time to catch up with the amplifier’s current demand.

short-duration musical peaks. Adding a pair of batteries with cold-cranking capacities of 600 amperes will provide extra current for short music bursts, but reserve power may still be depleted over longer music intervals. Adding more batteries will provide more reserve power and current, but no matter how many are installed, the alternator will still have to recharge them all.

If you plan to use the A6000GTi or A3000GTi in SPL competition, the charging system requirements will be much greater than those for normal music listening. Be prepared to add additional batteries and alternators to provide continuous current required for continuous duty.

See your authorized JBL car audio dealer for help in designing and installing an upgraded charging system to support your GTi amplifier.