Amp Location

[mattyb425]

Hey Guys, Im planning on rearranging my setup in the back. I have a 2005 Acura MDX and in the cargo area there is false floor storage are that would fit my amp and capacitor PERFECTLY!!! And with a little plexi and a few drilled holes, this would make an awesome looking housing....HOWEVER.... ive always been told its a very bad idea to mount an amp on the subwoofer box as the vibration can damage the internal hardware. So my question is, how bad of an idea would it be to place the amp and capacitor in front of the sub box?? before anyone comments, I am well aware I could just turn the box around, but I like the way it looks, and sounds when facing the rear... any comments or suggestions would be greatly appreciated... oh yea, in case it matters, I have 2 jl 13w3v3-4 wired down to 2ohm load, powered by Hifonics brx1600D

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[nismos14 5,000+ posts]

You can mount it on the sub box, it's not that crazy. A few people may have had their amps fail, but it's about the same failure rate as a normal amp going bad being mounted elsewhere.

 

[argenis69 10+ year member]

Hey Guys, Im planning on rearranging my setup in the back. I have a 2005 Acura MDX and in the cargo area there is false floor storage are that would fit my amp and capacitor PERFECTLY!!! And with a little plexi and a few drilled holes, this would make an awesome looking housing....HOWEVER.... ive always been told its a very bad idea to mount an amp on the subwoofer box as the vibration can damage the internal hardware. So my question is, how bad of an idea would it be to place the amp and capacitor in front of the sub box?? before anyone comments, I am well aware I could just turn the box around, but I like the way it looks, and sounds when facing the rear... any comments or suggestions would be greatly appreciated... oh yea, in case it matters, I have 2 jl 13w3v3-4 wired down to 2ohm load, powered by Hifonics brx1600D

Don't use the capacitor, it's more harm than good.

 

[mattyb425]

Don't use the capacitor, it's more harm than good.

Reasons why? I was originally considering a secondary battery, but after speaking to a few people it seemed as though my setup was a little small to require a secondary battery, so I went with the cap

 

[trumpet 5,000+ posts]

Reasons why? I was originally considering a secondary battery, but after speaking to a few people it seemed as though my setup was a little small to require a secondary battery, so I went with the cap

A second battery and a capacitor present an additional load on your alternator. If the alternator is struggling with your amplifier it's not going to do any better with a capacitor or a battery.

You have a second issue to consider. A capacitor is only going to provide power for a very brief time. The first big bass hit of a song is going to drain it, and if the song has continuous bass the capacitor is worthless until you pause the music or until there's a sufficient break for it to recharge.

There are conditions in which a capacitor is useful, but for heavy bass listening, not so much. There's a different type of capacitor that is much more useful when used correctly, but that doesn't apply to this situation.

Do the Big 3, use at MINIMUM 4 AWG OFC power and ground wire, and leave the capacitor out. 2 AWG wire is better, 1/0 AWG would be overkill but nice for the peace of mind and future power upgrades.

 

[mattyb425]

A second battery and a capacitor present an additional load on your alternator. If the alternator is struggling with your amplifier it's not going to do any better with a capacitor or a battery.
You have a second issue to consider. A capacitor is only going to provide power for a very brief time. The first big bass hit of a song is going to drain it, and if the song has continuous bass the capacitor is worthless until you pause the music or until there's a sufficient break for it to recharge.

There are conditions in which a capacitor is useful, but for heavy bass listening, not so much. There's a different type of capacitor that is much more useful when used correctly, but that doesn't apply to this situation.

Do the Big 3, use at MINIMUM 4 AWG OFC power and ground wire, and leave the capacitor out. 2 AWG wire is better, 1/0 AWG would be overkill but nice for the peace of mind and future power upgrades.

So should I consider upgrading the alternator? I was hoping something like that wouldn't be necessary with the 1200 watt amp. Ill have one pissed off wife If im blowing through alternators 2-3 times a year

 

[trumpet 5,000+ posts]

So should I consider upgrading the alternator? I was hoping something like that wouldn't be necessary with the 1200 watt amp. Ill have one pissed off wife If im blowing through alternators 2-3 times a year

I have no idea how hard you push your system, but if the amplifier is ever drawing its maximum current potential your factory alternator is probably not able to keep up. Even if you don't have voltage drop issues(presenting as dimming lights most commonly) the Big 3 upgrades under the hood should be done. Get your power delivery to the amplifier and back to the battery optimized.

 

[mattyb425]

Thanks for the advice guys, im gunna keep the cap in my garage incase I ever have a use for it. Ill see how it performs with the stock alternator and upgrade if necessary. still a little leery about mounting the amp directly in front of the subs... but im proabaly going to go ahead with it anyways unless I hear otherwise

 

[Chromatic]

So should I consider upgrading the alternator? I was hoping something like that wouldn't be necessary with the 1200 watt amp. Ill have one pissed off wife If im blowing through alternators 2-3 times a year

Your amp location will be fine. Just make sure temps are ok there.

As for the power draw, caps, alternator etc. I wouldn't install anything or buy anything just yet. I would monitor voltage during real world use and see where your voltage hangs and how low it dips while driving around listening to music. Just wire up a DMM or something to monitor voltage to a handy location and keep an eye on it. If it stays in a healthy range upper 13's-low 14's there is no reason you need to buy an alternator for a 1200watt amp setup. Every car make and battery are different.. MANY people do the "Big three" and it's really not needed with their specific setup.

The "big three" isn't going to make an average system (like yours and mine) sound any better.. it's just for more consistent and proper voltage levels. All of that said,.. it doesn't ever HURT anything. A High output alternator for example is not going to hurt even a stock car with no amp,.. as long as it's a proper alternator for the car and not pushing too much voltage to the battery.. after X volts in the higher range it actually causes some chemical reactions in the battery that at the very least will shorten battery lifespan. Again, this isn't an issue with a moderate HO alternator for your car.

For reference, I run a 900watt amp on four 6.5" mids at 70-80watts RMS, four 1" tweeters, and one 10" Sub -- And I have an active voltage monitor (they are cheap).. and my voltage stays a solid 14.5'ish all the time no matter how hard the system is being pushed. Different cars have better electrical systems stock than others -- Mine has a fairly decent stock setup and has room for some power draw, but I'm not pushing crazy power either. While some other cars electrical systems -- ie: Alternator mainly are JUST enough for what is stock in the car and not much else extra. Though *most* modern cars have some wiggle room.

I didn't ever consider the Big three as I couldn't justify a $200-$300 battery , X hundred HO Alternator, and using 0/1 Gauge wiring -- Instead I just used a 4Gauge kit, put a new "regular" $120 battery in the car and used a DMM initially to monitor voltage and also have an active real time voltage meter in the car -- as it's handy with or without a system imho.

I'm not saying you definitely don't need anything extra.. but it all comes down the voltage being supplied to the Amp.. if it's a solid steady figure in the right range.. you are fine, no need to waste money.

Further, you don't always need to buy the "big three" -- If your battery is good,.. then I assume you are probably using something like 4g wiring to your amp anyways (although if using 0/1 that's fine as well) -- Then all you would need at most is likely the HO alternator. Key is to spend money on just what you NEED, not what you hear other people have spent money on.

Your car is primarily running off your Alternator keeping charge while it's on anyways and the alternator is the biggest part of any power upgrade to a cars electrical system. So just keep an eye on those voltages and , I'd be willing to bet you are fine without any additional upgrades, esp. if your car isn't super old.

As for caps -- I'm not a fan of them for systems like yours and mine.. They keep X farads and as was said already they are literally good for a split second then that bit of "stored" charge is gone. Just in MY personal opinion most of them are an utter waste of money, and if one does buy them for a regular 600-1500watt system it should really be 90% for "looks" not to expect great things from it. //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif

That isn't meant disrespectfully.. you have one.. great. They are just highly over-rated in what they actually do in the real world aside from some considerably more expensive caps and these aren't needed on your "Average" system in the first place.

But as I often say.. do what YOU think you need if it will give you peace of mind.

 

[supra1987]

All cars are different but at 1200-1500 watts stock alternator should be fine.I would do big three just because its easy,cheap and effective

 

[mattyb425]

Your amp location will be fine. Just make sure temps are ok there.
As for the power draw, caps, alternator etc. I wouldn't install anything or buy anything just yet. I would monitor voltage during real world use and see where your voltage hangs and how low it dips while driving around listening to music. Just wire up a DMM or something to monitor voltage to a handy location and keep an eye on it. If it stays in a healthy range upper 13's-low 14's there is no reason you need to buy an alternator for a 1200watt amp setup. Every car make and battery are different.. MANY people do the "Big three" and it's really not needed with their specific setup.

The "big three" isn't going to make an average system (like yours and mine) sound any better.. it's just for more consistent and proper voltage levels. All of that said,.. it doesn't ever HURT anything. A High output alternator for example is not going to hurt even a stock car with no amp,.. as long as it's a proper alternator for the car and not pushing too much voltage to the battery.. after X volts in the higher range it actually causes some chemical reactions in the battery that at the very least will shorten battery lifespan. Again, this isn't an issue with a moderate HO alternator for your car.

For reference, I run a 900watt amp on four 6.5" mids at 70-80watts RMS, four 1" tweeters, and one 10" Sub -- And I have an active voltage monitor (they are cheap).. and my voltage stays a solid 14.5'ish all the time no matter how hard the system is being pushed. Different cars have better electrical systems stock than others -- Mine has a fairly decent stock setup and has room for some power draw, but I'm not pushing crazy power either. While some other cars electrical systems -- ie: Alternator mainly are JUST enough for what is stock in the car and not much else extra. Though *most* modern cars have some wiggle room.

I didn't ever consider the Big three as I couldn't justify a $200-$300 battery , X hundred HO Alternator, and using 0/1 Gauge wiring -- Instead I just used a 4Gauge kit, put a new "regular" $120 battery in the car and used a DMM initially to monitor voltage and also have an active real time voltage meter in the car -- as it's handy with or without a system imho.

I'm not saying you definitely don't need anything extra.. but it all comes down the voltage being supplied to the Amp.. if it's a solid steady figure in the right range.. you are fine, no need to waste money.

Further, you don't always need to buy the "big three" -- If your battery is good,.. then I assume you are probably using something like 4g wiring to your amp anyways (although if using 0/1 that's fine as well) -- Then all you would need at most is likely the HO alternator. Key is to spend money on just what you NEED, not what you hear other people have spent money on.

Your car is primarily running off your Alternator keeping charge while it's on anyways and the alternator is the biggest part of any power upgrade to a cars electrical system. So just keep an eye on those voltages and , I'd be willing to bet you are fine without any additional upgrades, esp. if your car isn't super old.

As for caps -- I'm not a fan of them for systems like yours and mine.. They keep X farads and as was said already they are literally good for a split second then that bit of "stored" charge is gone. Just in MY personal opinion most of them are an utter waste of money, and if one does buy them for a regular 600-1500watt system it should really be 90% for "looks" not to expect great things from it. //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif

That isn't meant disrespectfully.. you have one.. great. They are just highly over-rated in what they actually do in the real world aside from some considerably more expensive caps and these aren't needed on your "Average" system in the first place.

But as I often say.. do what YOU think you need if it will give you peace of mind.

A previous member said that it can actually do more harm than good? Even if I did use it just for "looks" and not expect too much performance, is there really any harm that can come from installing this? (and yes, I know how to do it properly lol)

 

[Chromatic]

A previous member said that it can actually do more harm than good? Even if I did use it just for "looks" and not expect too much performance, is there really any harm that can come from installing this? (and yes, I know how to do it properly lol)

In general.. it's very unlikely. However,.. you have to remember a Capacitor is placing additional strain on your alternator because it's keeping both the battery charged and the Cap.. ie: 1 Farad = 1000w (or so they say //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif ) -- I'm more of a fan of obtaining the proper alternator that will keep your amperage up when your Subs hit at your max volume you use in the mid to high 13v+.. If you put a meter on your electrical system, car running.. and crank it up -- And watch the voltage of the car running without the stereo running.. with alternator going .. make a note of this number -- Then Crank your stereo and subs up to the loudest you would normally ever play them.. Watch the voltage on those big bass hits -- If your voltage drops to like 13.2v or lower.. You need to upgrade your alternator even more rather than supplement your available "power" with a capacitor that stores X Farad that is used up in a split second. Make sense?

An alternator in a typical vehicle stock.. with a sufficiently powerfully amped system will have somewhere around 35-45amps to spare after it's powering the engine, interior lights, headlights, AC, and so on.. (AC pulls a lot of amperage).. A couple thousand watt subs RMS will eat all that 'headroom' your alternator has.. and this is where you get your dimming headlights and idle blips and so forth.

Now it isn't COMPLETELY unheard of to have some damage to an amp, etc due to a Capacitor being wired in series.. but I tend to think that's more due to external reasons, poor wiring, incorrect wiring.. other causes and being blamed on the Cap, etc. (But I'm really NOT super knowledgeable with experience using Capacitors in an audio setting).

Hope that makes sense.. and take it for what it's worth coming from me. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[Mass Car Audio 10+ year member]

You can mount it on the sub box, it's not that crazy. A few people may have had their amps fail, but it's about the same failure rate as a normal amp going bad being mounted elsewhere.

I beg to differ.