QuestionI currently have 2 alpine type r's in a vented enclosure pushed by a rockford fosgate 500-2 punch amp. I have recently aquired 2 more type r subs, and am currently searching the market for another rf punch 500-2 amp (since im satisfied with the current set up) and is capped w/a 1.0 farad rf non digital cap. do you know if i will need to increase to another cap or just feed both amps off the one cap. I am getting an optima yellow top amp before installing anything else. thanks. also do you know where i can find custom enclosure specs to build a great box w/o taking up too much room?
AnswerHi Tyler,
I think capacitors have a place in some car audio systems, but for a subwoofer system like yours they're not likely to make a very significant, audible difference. It certainly isn't hurting anything, but it's not really going to help anything either, whether you stick with a single cap or add another one. I'm not clear on whether you're planning to add the yellow top as a second battery, or replace your primary battery; but for normal use (with the engine running) the battery won't really make much difference either--although adding a second battery would probably be a mistake, unless you plan to use the system with the engine off.
When your Corolla's engine is running, the primary power source is the alternator. Every other electrical component--including the battery--is just a load on the alternator. If your alternator can keep up with the audio system's power requirements, then you shouldn't have a problem; if it cannot, then no amount of capacitors, extra batteries, or upgraded batteries will help the situation.
One thing you can do, if you haven't yet, is to upgrade the wiring in your vehicle's charging system. This is commonly called a "Big 3" upgrade on Car Audio forums. The Big 3 charging system wires are the wire between the alternator's output terminal and the positive battery terminal, the wire between the negative battery terminal and the vehicle chassis, and the wire (or ground strap) between the engine block and the chassis. In many cases, the stock wires are undersized for the current requirements of a high-powered amplifier; but they're just as important to your audio system as the main power wire that runs to your amp.
Sorry, I don't have a good site for a Type R box design, although you might want to check out JL Audio's web site "support" link. They have some excellent tutorials and information on box building. Also, one way to reduce the space requirements for your sub box would be to switch from a ported design to a sealed design. Ported boxes require more air space than sealed boxes, and with two more subs to fit in, you might run out of room for a ported setup. The feedback I've heard on the Type R suggests that you might get better performance out of a sealed box on the high side of the recommended range, compared to a ported box that's undersized.
Hope this helps!
Brian
