I'm wondering how large a capcitor I need to run for my setup. I have a 400w Coustic amp driving 2 Coustic 10's and a Sony head unit driving my front 4 speakers. When the bass hits at idle, the lights and head unit faceplate can dim and occasionally the CD cuts out. I also have another 300w Coustic amp I want to use to drive the front 4 speakers, but I figure I'll need a capacitor before I add it. Would a 1 farad capacitor be enough? I've never had a system with a cap before and one of the local shops is trying to sell me a 5 farad cap, which seems like a hell of a lot...

TIA,
Eric

 

A general rule of thumb is to use one farad of capacitance per 1kW of power you are using. In your case, one farad would be enough.

I'm surprised that you are suffering that ammount of dimming from that amplifier. Have you gotten either your battery or alternator checked lately?

 

it's not just the amp that is drawing current. he might have more than one electrical unit in his car maybe?

 

5 Farads is ridiculous, like he said, 1 farad is plenty.

 

They must be trying to sell you the Alumapro 5 Farad cap. It has a lot more capacitance but for not too much money. And it looks cool. But the downside of it is that the thing only takes a single 4 gauge input... which is sort of on the small side, IMO. **** for 5 farads of capacitance, I'd want to run a 0/1 gauge into it. Also, some people claim that it does it discharges too slowly.


[Modified by dc24me, 12:49 AM 4/5/2002]

 

That is true, but I really can't think of a honda accessory that will be drawing more current than an amplifier. An amplifier is normally drawing so much current that any other accessories (neon, fans, etc) are insignificant when you look at the whole picture.

 

Nope, no other electronics on board and the battery is a brand new Honda OEM battery...

Thanks for the replies, I imagine I'll go with the 1 farad cap - I don't have any plans to go beyond adding the second amp, so that should be fine.

Eric

 

i have a yellow top optima second battery and 2 i farad caps and experience no dimming at all with a soundstream 702 (700 x 1 @ 4 ohms, im running it at 3) mcintosh mc427 (100 x 2) and ppi 25 x 2