Do I need a capacitor?
11-14-2006, 02:54 AM
#1
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Do I need a capacitor?
Do I need to install one? Are they worth while? I have an alpine 400w mono amp driving a single Fosgate Punch 2 12" sub and a Alpine 300w 4-channel amp driving Focal components in the front and 2-ways in the rear
11-14-2006, 04:36 AM
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Re: Do I need a capacitor?
Originally Posted by Box-ster
Do I need to install one?
Originally Posted by Box-ster
Are they worth while?
Originally Posted by Box-ster
I have an alpine 400w mono amp driving a single Fosgate Punch 2 12" sub and a Alpine 300w 4-channel amp driving Focal components in the front and 2-ways in the rear
11-14-2006, 04:45 AM
#3
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You dont have to install a capacitor, but i would recommend that you do. Depending on how much you crank your music , your amps may require that extra amount of juice and thats where the Cap comes in. Think of a cap as a Power regulator or RedBull for your amps... When your amp needs that extra kick when certain low frequencies hit, rather then going directly to the battery its already at the cap and can get it rite there. A capacitor isnt ment to replace a battery , its more or less there to assist in distributing power to your amps when they need it the most. Also SOMETIMES but not GAURANTEED, a capacitor may help reduce the dimming of lights and may help in reduceing ground noise found in some 4 channel amps. Also the preformance of the amps can also be determined by what size power wires you have, how your ground cables are grounded, and what type of battery you are running. In some cases you may not need a cap at all.
11-14-2006, 08:46 AM
#4
Bbcollins, please help me on my amp
i have a 456watt infinity amp powering a 12inch infinity sub. the "CLIP" led light blinks on my Infinity amp. The manual said "The amplifier is being overdriven" I haven't see the lights dim yet.
Do i need a cap? i have the stock battery , should i get yellow top?
i have a 456watt infinity amp powering a 12inch infinity sub. the "CLIP" led light blinks on my Infinity amp. The manual said "The amplifier is being overdriven" I haven't see the lights dim yet.
Do i need a cap? i have the stock battery , should i get yellow top?
11-14-2006, 08:58 AM
#5
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gamma, turn down the gain on your amp and it should be solved. when it is being "overdriven" it means you are sending soo much signal into the amp thus overdriving the input.
if your lights arent dimming, you dont necessarily need a cap, but as bbcolins said it is a recommendation to have one installed for those "just in case" moments when your music just hits too hard.
but all in all, turn down the gain on your amp and your should be ok.
if your lights arent dimming, you dont necessarily need a cap, but as bbcolins said it is a recommendation to have one installed for those "just in case" moments when your music just hits too hard.
but all in all, turn down the gain on your amp and your should be ok.
11-14-2006, 01:02 PM
#6
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If you are running a serious system....you need a cap! Capacitors discharge much faster than a battery. Capacitors are essentially a holding tank for quick bursts of power. The holding tank needs to be refilled though. The stock charging system is kind of shady so lights will most likely still dim with continuous cranking!
Good Luck
Good Luck
11-14-2006, 04:40 PM
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The charging system on an xB is weak, at best. Save your money and buy a higher output alternator. A capacitor acts as a quick disbursement of stored voltage when needed. It does not generate any more current than the system is already creating. If you are experiencing a noticeable dimming of lights and other electronics, then it's time to upgrade the charging system before you cook some of those valuable amplifiers!
11-14-2006, 08:29 PM
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Originally Posted by UV7
The charging system on an xB is weak, at best. Save your money and buy a higher output alternator. A capacitor acts as a quick disbursement of stored voltage when needed. It does not generate any more current than the system is already creating. If you are experiencing a noticeable dimming of lights and other electronics, then it's time to upgrade the charging system before you cook some of those valuable amplifiers!
11-15-2006, 01:34 AM
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Hey Gammatnt.. The other replies are correct in turning down the gain.. however you may have some other things going on if the problem persists.. did you install it or was it installed by a company. On some infinity amp models the ohm load is only 2ohm and if you have a dvc sub thats 2ohms per coil then that may mean your amp is running at 1 ohm (depending on how it is wired, there are other wiring varations), this is the most common, and if it is, infinty amps ,depending on the model, dont run to well at 1ohm loads. Also something else might be an issue if not the amp or gain adjustments.. it may be the sub itself.. if the sub itself is off its rated ohm rating then that may cause certain clipping also, you would know by having it tested by using a meter set to ohm or have it tested (most places do it for free) at a local shop. There are other possibilities such as even having a bad amp out of the box (it does happen from time to time). Also check your wires, power cables, rcas, ground wire etc.. its always best to try to figure out your situation by doing a process of elimination. If all else fails have your equipment bench tested at a local shop (beware if they have an excessive fee to just test your equipment). Well i hope this may help you out and any other readers that may have the same situation 
11-15-2006, 01:39 AM
#11
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Thanks for the responses. This is my first "real" system. so hang with me here;
If I experience my lights dimming I should upgrade the alternator and/or the battery?
Another note on the cap, my daughter works for a big box electronic store so I can get one for cheap with her discount. Having said that, if you could buy a cap for 1/2 off retail would you install one and if so how big for my system? Do I need one for each amp or should I just put one on the sub amp? I am not trying to just throw money at this, but thinking of taking advantage of the big discount to get a little extra out of my system. And yes I will be cranking it up even though I am older then most of the people on this forum
I still like my music
If I experience my lights dimming I should upgrade the alternator and/or the battery?
Another note on the cap, my daughter works for a big box electronic store so I can get one for cheap with her discount. Having said that, if you could buy a cap for 1/2 off retail would you install one and if so how big for my system? Do I need one for each amp or should I just put one on the sub amp? I am not trying to just throw money at this, but thinking of taking advantage of the big discount to get a little extra out of my system. And yes I will be cranking it up even though I am older then most of the people on this forum
I still like my music
11-15-2006, 02:43 AM
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A simple way to view this topic is this:
If you are planning on making a fairly large audio system with multiple amplifiers pushing several speakers and multiple subs, then you are going to draw a considerable amount of power from the charging system of the car.
Example:
Say you have two amps on highs, one pushing out 100 watts X 2 channels, and one pushing 50 X 2, plus a mono amp pushing 1000 watts on some 12s. You have a total of 1300 watts in output.
Using the formula, P=V x I, where P= Power (watts), V=Volts, and I=Current (amps):
1300 watts @ 14 volts (average for a normal output alternator while running) = 92 amps of current! Considering that the stock alternator only generates approximately 80 amps of current, you can see where this setup would lead, and we haven't even calculated in the current draw from the car's normal electronics! You can buy all the batteries and capacitors in the world, but they are not going to generate any more current for your car.
Another fact to consider is this: Most consumer electronics do not respond well when they are not receiving adequate current to perform, especially high-current amplifiers!
I hope this helps out.
If you are planning on making a fairly large audio system with multiple amplifiers pushing several speakers and multiple subs, then you are going to draw a considerable amount of power from the charging system of the car.
Example:
Say you have two amps on highs, one pushing out 100 watts X 2 channels, and one pushing 50 X 2, plus a mono amp pushing 1000 watts on some 12s. You have a total of 1300 watts in output.
Using the formula, P=V x I, where P= Power (watts), V=Volts, and I=Current (amps):
1300 watts @ 14 volts (average for a normal output alternator while running) = 92 amps of current! Considering that the stock alternator only generates approximately 80 amps of current, you can see where this setup would lead, and we haven't even calculated in the current draw from the car's normal electronics! You can buy all the batteries and capacitors in the world, but they are not going to generate any more current for your car.
Another fact to consider is this: Most consumer electronics do not respond well when they are not receiving adequate current to perform, especially high-current amplifiers!
I hope this helps out.
11-15-2006, 01:11 PM
#15
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Above is correct. But keep in mind most high output alternators need to be spun fast to get the peak output numbers. Idleing in traffic or at an audio show will show some problems still. Batts and caps are simply bandaids......but if you are bleeding, bandaids are good.
11-15-2006, 01:38 PM
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That is not entirely true. A higher output alternator is going to generate more current across the entire spectrum, not just at high revs.
Most competition vehicles that run HUGE stereo systems have multiple batteries that are run off an AC charger while at show. This enables them to run continuously without the need to start the vehicle from time to time. They use power capacitors for multiple purposes. Capacitors act as a small battery that can charge and discharge very quickly, providing power when needed, but they also can provide a sort of regulation that keeps the amplifiers pulling a consistant amount of power every time. This is why they are sometimes referred to as "stiffening" capacitors. They "stiffen" up the power to keep things consistant.
But what happens if there is not enough current to keep the cap charged? It cannot discharge an even, regulated supply of voltage if its own charge is not being maintained. This is why I do not recommend that people purchase a capacitor if they are already suffering from severe current drain as it is. They will not see enough positive results to warrant the purchase of the cap, and will eventually need to buy a high output alternator anyways.
Most competition vehicles that run HUGE stereo systems have multiple batteries that are run off an AC charger while at show. This enables them to run continuously without the need to start the vehicle from time to time. They use power capacitors for multiple purposes. Capacitors act as a small battery that can charge and discharge very quickly, providing power when needed, but they also can provide a sort of regulation that keeps the amplifiers pulling a consistant amount of power every time. This is why they are sometimes referred to as "stiffening" capacitors. They "stiffen" up the power to keep things consistant.
But what happens if there is not enough current to keep the cap charged? It cannot discharge an even, regulated supply of voltage if its own charge is not being maintained. This is why I do not recommend that people purchase a capacitor if they are already suffering from severe current drain as it is. They will not see enough positive results to warrant the purchase of the cap, and will eventually need to buy a high output alternator anyways.
11-15-2006, 01:45 PM
#17
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Originally Posted by Box-ster
What is a "big three upgrade"?
11-15-2006, 11:55 PM
#18
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Originally Posted by UV7
That is not entirely true. A higher output alternator is going to generate more current across the entire spectrum, not just at high revs.
Most competition vehicles that run HUGE stereo systems have multiple batteries that are run off an AC charger while at show. This enables them to run continuously without the need to start the vehicle from time to time. They use power capacitors for multiple purposes. Capacitors act as a small battery that can charge and discharge very quickly, providing power when needed, but they also can provide a sort of regulation that keeps the amplifiers pulling a consistant amount of power every time. This is why they are sometimes referred to as "stiffening" capacitors. They "stiffen" up the power to keep things consistant.
But what happens if there is not enough current to keep the cap charged? It cannot discharge an even, regulated supply of voltage if its own charge is not being maintained. This is why I do not recommend that people purchase a capacitor if they are already suffering from severe current drain as it is. They will not see enough positive results to warrant the purchase of the cap, and will eventually need to buy a high output alternator anyways.
Most competition vehicles that run HUGE stereo systems have multiple batteries that are run off an AC charger while at show. This enables them to run continuously without the need to start the vehicle from time to time. They use power capacitors for multiple purposes. Capacitors act as a small battery that can charge and discharge very quickly, providing power when needed, but they also can provide a sort of regulation that keeps the amplifiers pulling a consistant amount of power every time. This is why they are sometimes referred to as "stiffening" capacitors. They "stiffen" up the power to keep things consistant.
But what happens if there is not enough current to keep the cap charged? It cannot discharge an even, regulated supply of voltage if its own charge is not being maintained. This is why I do not recommend that people purchase a capacitor if they are already suffering from severe current drain as it is. They will not see enough positive results to warrant the purchase of the cap, and will eventually need to buy a high output alternator anyways.
11-16-2006, 04:08 AM
#19
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the only thing a cap will do is unsure a consistant pull when supplied enough energy by the altenator. Bats generaly have a norm voltage of 12.8v while Caps can hold the charging voltage of the altenator of anywhere from 13.8-14.4v. it's not alot of headroom for kicks, bt does help to a point. if you'r using a massive settup, caps are pointless. personaly, i DON'T recommend caps as they wont help much at all. upgrading you'r altenator and getting a heavier duty bat will help ALOT!!!!!!! more then a cap will.
a Cap can only store energy that it's supplied and when it's discharged, it's almost instant and full force at once. if you do a test between a battery and a cap. say you somehow have a cap that has the same amount of energy as a full bat of the same capacity, the cap will supply a great deal amount of energy, but only for a couple seconds. the bat on the other hand will peak up for a LONG time as it's a chemical energy supply while the cap is a electron build up and it's all discharged at once.
as for clipping on the amp, amp clipping is not from too much input signal, it's from too much throw. you can counter this by turning the gain down and making sure that the onboard EQ is properly configured and not just "FULL BLAST" bass boost. an improperly setup EQ can cause MASSIVE amplifier VA problems resulting in clipping or thermal-meltdown. Clipping in general is when the amplifier is trying to throw more then what it's capable of throwing.
image two parallel horizontal lines like so...
--------------------------------------------
--------------------------------------------
this is an amps head room for the output signal. now when you have a clean signal you'r headroom would look like this...
--------------------------------------------
/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\
--------------------------------------------
the zigzag line being the output signal within clean power ratings. now when you get clipping you get this... *NOTE: i had to put int he middle line to make the example, imagen that it's not there*
--/--\------/--\------/--\------/--\--
-/----\----/----\----/----\----/----\-
/------\--/------\--/------\--/------\
you'r signal then turns from an AC current to a DC current. DC current causes a static effect on the VC of the woofer and will fry the VC within very little time. just turn your gain down. if you still are having a problem, heres what you do. turn you'r gain all the way down on your amp, go to you'r deck, throw in a song, blast is as loud as you would normaly blast it, go to the back and raise the gain of the amp to a point where the clipping like just barely flickers. you may loose a bit of you'r bass heavy sound, but at the same time you'l be sure that you wont ruin any of you'r equipment. later on, i would recommend that you look into an amp thats capable of supplieing 25% more power then the subwoofer's RMS rating. this insures that you'll have the headroom to play with.
a Cap can only store energy that it's supplied and when it's discharged, it's almost instant and full force at once. if you do a test between a battery and a cap. say you somehow have a cap that has the same amount of energy as a full bat of the same capacity, the cap will supply a great deal amount of energy, but only for a couple seconds. the bat on the other hand will peak up for a LONG time as it's a chemical energy supply while the cap is a electron build up and it's all discharged at once.
as for clipping on the amp, amp clipping is not from too much input signal, it's from too much throw. you can counter this by turning the gain down and making sure that the onboard EQ is properly configured and not just "FULL BLAST" bass boost. an improperly setup EQ can cause MASSIVE amplifier VA problems resulting in clipping or thermal-meltdown. Clipping in general is when the amplifier is trying to throw more then what it's capable of throwing.
image two parallel horizontal lines like so...
--------------------------------------------
--------------------------------------------
this is an amps head room for the output signal. now when you have a clean signal you'r headroom would look like this...
--------------------------------------------
/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\
--------------------------------------------
the zigzag line being the output signal within clean power ratings. now when you get clipping you get this... *NOTE: i had to put int he middle line to make the example, imagen that it's not there*
--/--\------/--\------/--\------/--\--
-/----\----/----\----/----\----/----\-
/------\--/------\--/------\--/------\
you'r signal then turns from an AC current to a DC current. DC current causes a static effect on the VC of the woofer and will fry the VC within very little time. just turn your gain down. if you still are having a problem, heres what you do. turn you'r gain all the way down on your amp, go to you'r deck, throw in a song, blast is as loud as you would normaly blast it, go to the back and raise the gain of the amp to a point where the clipping like just barely flickers. you may loose a bit of you'r bass heavy sound, but at the same time you'l be sure that you wont ruin any of you'r equipment. later on, i would recommend that you look into an amp thats capable of supplieing 25% more power then the subwoofer's RMS rating. this insures that you'll have the headroom to play with.
11-16-2006, 05:09 AM
#20
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Cap are a great bandaid for a quick fix! The proper way to fix a low voltage is upgrade altanator then upgrade the battery, then use a cap if needed. the only thing a cap does is store energy for very very short burst all they do is take a major draw off the wire keeping a regulated power supply thus why some amplifier company have regulated power supply's in which a cap will do nothing in some cases.
Small system may not need a cap but you can always stiffin the power supply with a better battery I would recomened using a dry cell maintance free battery. These are some of the best batterys out there for Car audio and Boat audio.
Small system may not need a cap but you can always stiffin the power supply with a better battery I would recomened using a dry cell maintance free battery. These are some of the best batterys out there for Car audio and Boat audio.