Capacitors

[nate-vy]

Hey audio gurus
Ive just about gathered all my audio gear and I'm wondering if I need a capacitor or two

Specs on amps and subs are as follows :

Pioneer GM-D8400M 1200w class d mono
Pioneer TS-sw2501s4 4 ohm 1200m/300n slim subs x2

Pioneer GM-5400T - 250w x 2ch amp
Pioneer TS-D1720C - splits 260m/60n

Pioneer Deh9350sd head unit runing them

Not real up with the gear but I think its all suitable
Any info or recommendations are welcome
All the gear listed I already have
Just after some info on whether a capacitor is required or recommended
and size of capacitor or general rule of sizing

Cheers guys
Nate

[2LOUD2OLD]

No need for one, save your money

[Nic92]

i was using a 2 fared cap at 500rms then when i got a 1200rms amp i got a soundstream Scell-600 for about $280, its like another battery but it works as a capacitor aswell, it is great to get if you dont want to upgrade your alternator or front battery or w.e

[TigerAudio]

With caps, there is no right or wrong. For this reason, I done my research on them and got the following answers:

"Something to remember is that a capacitor is nothing more than a small battery. It's main benefit, however, is that it has a lower internal resistance than a bigger battery, which means it has a faster discharge ability. All batteries have discharge and recovery rates and they are determined by two things, internal and external resistance. Why this is important to understand is that the more resistance that you have between the amplifier and a battery, the slower the battery will respond to the immediate current demands of the amplifier. That's where voltage dropping occurs. The thought is that if you place a cap back by the amps, you have effectively decreased the resistance between a battery source and the amp. The amps will draw from the caps first, then the main battery after it "catches up".

Ultimately, it all comes down to ohms law and basic electronics. The ultimate goal for a system, regardless of whether it's for ground pounding or for SQ, is to minimize resistance. Larger power and ground wires will do that, but also make sure that you have minimized the resistance from the Alternator to the battery as well as the battery to the frame. Make sure you pay as much attention to the ground side as you do the power side. The power circuit is a complete loop and the voltage will drop across the weakest link.

One other thing to think about is that most amp manufacturers these days provide enough internal capacitance to handle transient needs, so adding a cap is usually not necessary. In the old days, amp manufacturers were a bit light on the internal capacitance."

"You typically don't see capacitors in SPL vehicles because so much care is taken in minimizing the distance and resistance between the batteries and the amplifiers. The discharge and recharge rates are a matter of resistance. More resistance, slower charge and discharge. That being said, the caps inside the amplifier will more than likely have a lower internal resistance than a large farad cap, so the current will go the least resistance, so I'm not sure if your theory holds up.

Bottom line for caps, I would definitely recommend them for SQ purposes only if the battery is in the front of the car and the amps are in the back. Other than that, they really don't have much use, other than looking cool. Personally, I'd spend the money to upgrade the wiring and pay close attention to all of the connections, power and ground."

Hope this helps

[Nic92]

you shouldnt need a cap, try it out first without a cap and if it cuts out when its cranked, or if it dims lights etc etc then it would sound alot better with a cap, i needed a cap witha 500rms class a/b amp but it was 57% efficency and it used to cut out but since its a class D amp you should be fine