1 Farad Capacitor or Bigger Battery?

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1 Farad Capacitor or Bigger Battery?

Post by Sublevel »

Hey Guys,

I just migrated my stereo setup from my old car into my FTO and I'm having some voltage drop issues whilst idling, it's fine whilst I'm driving but at idle the volt meter needle sits around 13v and drops to 12ish every 20-30secs [or when the bass hits hard]. I'm using a 500w RMS Precision Response amp and a JBL 12" Sub.

Do you think I should get a 1 Farad capacitor or a bigger battery?

[was thinking Exide Orbital or similar for the battery :D]
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J
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Post by J »

bigger battery ftw
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rock_it
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Post by rock_it »

I had a Schnider 1 farad running a standard batt, powering :

1 Rockford Fosgate punch 100ix2
1 " " 400 gold seris
1 " " 800.1
2x Alpine type R Subs 12"
2x Boston Pro Rally 6"
2 sets of Boston Pro Accoustic 6.5" splits

Then had the 2 Tv's and DVD ...

Never had a problem at idle....
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vipfto
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Post by vipfto »

its norm but the stock FTO batt is pathetic get a bigger one
to be honest a capacitor not really needed unless you are drawing massive power ie bigg MF amp or two amps etc
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Post by Sublevel »

Cheers for the advice guys :D Think I'll just go get the Exide Orbital...I had a 400CCA Bosch in the last car and had no voltage drop whatsoever with the same setup, so the Exide's 700CCA should just about do me :lol:
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Post by rock_it »

Sublevel wrote:Cheers for the advice guys :D Think I'll just go get the Exide Orbital...I had a 400CCA Bosch in the last car and had no voltage drop whatsoever with the same setup, so the Exide's 700CCA should just about do me :lol:
Where you getting the 700cca from .. And how much .. ?
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koolio1234
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Post by koolio1234 »

If you still get voltage drop with the new battery could be an alternator issue.
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Post by msbchi »

think about it. A capicitor is a reserve power supply that will step in when the battery power is to low , but will then drain more power from your battery when it loses power. Get a bigger battery!
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Post by Jamie »

My guess is that your alternator is on its way out. I dont think it will help if you install a bigger battery or capacitor because if your alternator cant supply the current neither of the other two will have it.

However if you do buy a bigger battery maybe install it in the boot near your amp and use large diameter cables to avoid voltage drop.

Also not sure what you think a capcitor does but I can tell you now that it is almost complety useless on all but high end competion installs.

Just my 2 cents worth. Hope this helps ;)
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Post by alekazam »

I think both a 1farad capacitor is only $70 and the rule of thumb is 1 farad for every 500w. I know there are a lot of sceptics regaurding capacitation in car audio but if it didn't work it just wouldn't have survived the rapid evolution of car audio which dumps any technology that holds it back really quickly.
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Post by Jamie »

Seriously I think installing a capacitor is a waste of time unless you are powering digital amplifiers. If you think about it there is no possible way can a capacitor can provide more than the source voltage or current. Capacitors in DC circuits are used for filtering. Basically every time the supply voltage drops below 14.4v the capacitor discharges a little to make up the voltage. It is also used to supress noisey DC but thats another story.

1 Farad capacitor for every 500 watts. Marketing scams sorry. 500 watts at 14.4 volts would be a current draw of 34.72 amps at maximum volume. Well below what your alternator should be able to deliver.

Before you waste $70 on a capacitor check your battery. Have you got a mate with similar sound system? If so swap batteries and see what happens.
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Post by alekazam »

Jamie wrote:Seriously I think installing a capacitor is a waste of time unless you are powering digital amplifiers.
Before you waste $70 on a capacitor check your battery. .
Jamie, I agree that a battery is Sublevel's first priority and I would have agreed with you about big caps being a waste of money back when thay were $400. But for the cost of lunch for two in a mediocre resturant I can't think of a cheaper and more effective way of shoring up your sound system's power supply. After all it costs a lot more than that for half way decent cabelling.
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Post by Jamie »

alekazam wrote:
Jamie wrote:Seriously I think installing a capacitor is a waste of time unless you are powering digital amplifiers.
Before you waste $70 on a capacitor check your battery. .
Jamie, I agree that a battery is Sublevel's first priority and I would have agreed with you about big caps being a waste of money back when thay were $400. But for the cost of lunch for two in a mediocre resturant I can't think of a cheaper and more effective way of shoring up your sound system's power supply. After all it costs a lot more than that for half way decent cabelling.
Look not trying to have a go at you. This is very hard to explain in a post and I'm not the best at explaining things.
-A capacitor in a circuit with small diameter cabling will essentially do nothing. If you have voltage drop between the battery and capacitor, the capacitor will only charge to the battery voltage minus the voltage drop anyway.
-The only way to prevent this is with decent cabling in the first place.
-Cabling doesn't have to be expensive. Call up some electricians and buy some cheap offcuts.
-A 1 Farad capacitor is fn huge. That sort of capacitance isn't necessary. In a power supply a 500 micro Farad capacitor is considered fairly big. Thats equal to 0.0005 Farads.
-If you bought 3x 16 Volt, 500 mic capacitors. Then paralled them up and mounted them on a bit of circuit board it might cost you $10 at most.
-The above will do the same thing and makes that $70 look expensive.

Let me know if any of that made sense, like I said I'm not the best at explaining things.

Hey with the left over money you could go to that medicre resturant :lol:
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Post by zapp »

hi all England calling ,im running a 50 ( yes fifty) farad cap on my FTO install due to the fact im running two 4 channel 36volt Phase Linear amps with a external power supply when the bass drops (sub tuned to 27 hz ) everybody knows im home
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Post by ftokiwi »

caps are a waste of money imho. the problem is the alternator in the fto- its simply to small. a battery is the easiest and cheapest way to upgrade your supply. orbitals and optimas have never let me down. without going into all the details i had an fto alternator tested full load after i took out my 2nd alternator in 12 months (car audio comp)on full load (no stereo but lights/ac etc all on the alternator read -5 amps. in the last comp I ran 12x1 Farad caps-alternator failed. this was after the comp(reading taken with the engine off in comps) all the top cars did runs with the engines going to see what they could do. "maybe" caps do something upto 500wrms? but at 1kwrms + i doubt caps do anything.
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Post by bduffman »

digging up a old post but basicly a lot of people think caps will be the answer and there wrong its just one more thing that will drain your battery if u have your sub pumping its going to be drawing from battery and cap then the cap will draw from battery and them stock batterys are a peice of sh*t i have a blue top ( same as yellow but with extra terminals ) and it works great i had a 600rms amp and two smaller 2 channal amps running a ps2 , inverter , neons ect and i never had any issues upgrade your battery and wires and u wont have any issue might cost you $500 or so but in the long run well worth it i just installed my blue top from my old car into the fto fits like a charm just got longer mounting rods and done upgraded the ground while i was at it took like 20 mins

btw your grounds are just as important as your power if any thing more important
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Post by nathan »

i have a century marine battery on mine, i ended up overdrawing the system and screwing my alternator, with help from a 1500WRMS option audio mono blocks and 600W 4 channel lol
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Re: 1 Farad Capacitor or Bigger Battery?

Post by Azz41 »

jamie is kinda on the money... caps in series add up, parallel it is 1/2 or what ever... it works opposite to resistance... i am a sparkey and have just done my time... i would suggest a bigger battery unless you have massive draw then a cap would also be needed... the cap is used to stabalize to draw on the battery, so its not a massive hit at once
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