role of capacitors in car audio

Like to understand what kind of capacitor and what value has to be used for my Monoblock amplifier? Most guys around say that 0.5Fd capacitor is enough for 500Wrmc amplifier.... is this true?.  The capacitor I have from Scosche 1Fd with Display does show me the battery voltage  - why does this voltage keep varying, is this normal? and after some time roughly about 10min the display goes blank - does this mean the capacitor is switched of is it a bad capacitor?

I feel the amplifier are power hungry devices and requires more power as when the Sub needs. the capacitor stores the power and delivers the same when the amplifier needs to give a good/big throw to the sub. I have noticed my car Ford Fiesta (diesel version) facing typical problems, I have 2 RF amplifiers one the 4channel amp driving 2pairs of RF components in the front - 2pairs of RF coaxial speakers at the rear and the monblock driving @ big RF 12inch Subwoofer in a sealed enclosure. when the music is loud the acceleration goes up and my headlights dim and dip as the music delivers high bass, on advice I did install a hybrid capacitor 10Fd from Stinger, the same problem persists (not much difference), what could be the problem.

The majority of people on this board will tell you not to install a cap at all, instead fix the real problem.

The real problem being that your electrical system is not capable of producing enough power to power your accessories and your stereo.

Upgrade the "big 3" and if the problem persists you may want to consider upgrading your battery and/or alternator.

Thank you very much for the much needed information.

Big 3 Means

• the wire from the battery's negative terminal to the car's chassis (ground).
• the wire from the alternator to the battery's positive terminal.
• the wire from the chassis (ground) to the engine.

Am i right.

Also 1 more question why does the display go off after some time. How do I keep the display on completely.