Audio/Visual Electronics Wired up? Everyone's got some sort of electrical modification. Let's hear about it here.

Audio Information

Thread Tools
 
Search this Thread
 
Old Dec 19, 2008 | 03:33 PM
  #31  
95slvrZ28's Avatar
Overdrive Member
Joined: Aug 2006
Posts: 4,496
From: Boulder, CO
Default RE: Audio Information

ORIGINAL: 95slvrZ28

Sorry Hiss, I'm going to have to disagree with you here. Number one, I think you're getting a few of your terms mixed up. It's not a matter of how much voltage you can put out it's the amount of current you can supply. I can output 25 volts but only be able to provide 1mA of current. Likewise I can get almost infinite current (read electric arc) for a short amount of time with a potential of only 25 V. If anything I would argue that a slow discharge capacitor would relieve the strain on your electrical system and here's why. The time constant of a capacitor to charge/discharge is RC where the resistance is in series with the capacitor. If you don't have a capacitor the capacitance of your power providing system is only dependent on the innate capacitance of the wires and other components,we'll assume this is zero for the point of the argument. This effectively means the time it takes to discharge the entire system is instant (in all reality it's not, but it's pretty close...). If you have a capacitor you are simply increasing the amount of time the electrical system has to respond to any given current draw. This means that although the alternator has to run a little longer it doesn't have to work as hard while it's doing so. Either way you look at it the energy has to come from somewhere, if you use a cap in the immediate sense it comes from the cap and then gets recharged over time, and if you upgrade the big 3 it comes instantly. A cap doesn't mean you use more energy, it just gives you some room for your system to catch up.
Sorry, that's how it should be, I made a little mistake there, nonetheles...
 
Old Feb 22, 2009 | 02:02 PM
  #32  
Freshcamaro's Avatar
In the Staging Lanes
Joined: Feb 2009
Posts: 40
Default

Well i install audio an visuals for a living and a capacitor is the best way to go. once your cars started you can take the battery out and itll still go. yea the big 3 is good an cheaper but it also depends on your system. anything over an 800 watt and i would strongly consider a capacitor. it dosent matter though if its 800 or 1800 theres still going to be a draw from ur car no matter what ur running. a capacitor helps your amp with a quicker response time in hittin the lows. and it depends on your wiring. what gauge ur running to what size amp and what size are you running from that amp to the subs.
 
Old Jun 29, 2009 | 10:15 AM
  #33  
malvenus's Avatar
Newbie
Joined: Jun 2009
Posts: 7
Default

in the long run i would actually prefer an audio cell in the back of my car. same basic setup as the cap, but last alot for more shots. when i was runnin an 1800 watt back end(6x9's max 400, 15" sub max 350, 1800 watt amp never pushed to limit, plus crossover) the audio cell gave me a much better solution because it saved the headlights from dimming and recharged when i was driving in areas where loud sound wasnt exceptable(stupid neighborhoods!). all in all it was a dream for me who was better suited to buy a $160 cell rather than a $300 alternator plus all the wire needed(at the time i drove a neon, and alterators with a decent amount of power are pretty pricey....).
 
Old Aug 10, 2009 | 06:51 PM
  #34  
RFxCamaro's Avatar
3rd Gear Member
iTrader: (1)
Joined: Jun 2008
Posts: 1,096
From: Sacramento
Default

if you had a true 1800 watt system you would need more than one 160 battery. a decent battery cost anywhere around $200 and that covers a lil more than 1000rms
 
Old Aug 11, 2009 | 08:21 AM
  #35  
malvenus's Avatar
Newbie
Joined: Jun 2009
Posts: 7
Default

the audio cell in the back was an 800 kinetik. it could have started my car with no issue and I used it for a few jumps lol. loved it but your right it was around 180 or 200 so it wasn't as cheap as a standard battery, but it is non-spillable which more than makes up for it to me.
 
Old Aug 20, 2009 | 01:21 PM
  #36  
macker's Avatar
Newbie
Joined: Aug 2009
Posts: 3
Default

Short version: The cap is always a band-aid, but sometimes it's the most practical, in very high-wattage systems. There's benefits to doing a Big 3 upgrade, more than just not seeing your headlights dim, it's cheap, and it doesn't burn out over time like a cap does. If running a cap makes you feel better, do it, a properly functioning cap wont make anything worse. But a wiring upgrade may solve the problem, including some you didn't know you had.

Long version:

Eh, may as well add two more cents.

Car electrical equipment is designed to run in a voltage range, ~10-14V, 12V nominal, but really it wants 13.8V, which is what you should typically see on a car with a properly operating charging system, while the engine is running. Under heavy current draws, you'll see the voltage drop (sag). As a temporary condition, equipment will live, but it's never happy about it, particularly when it fluctuates frequently.

The reason for this is under heavy current pull, the resistance on the wire is going to start going up, reducing the capacity of the wire to flow current. This problem is exaggerated by the low voltage that cars operate on; high voltage "flows better", which is why the utility company flows at 30-100kV, stepping down as they get closer to your house, with 120/240V service for residential, or 480/600V for commercial.

Now if your sub is causing brownouts (just like a house light-bulb going dim when a big electrical appliance kicks on), then a cap may be an answer. It's certainly a cheaper and simpler alternative than running two batteries and an HO alternator. But, the better question is, what's the weakest link?

The 'Big 3' were sized for the cars original electrical system, assuming all factory options are installed, and may have a ~20% overhead in rating. This isn't so you can add accessories (other than cig lighter adapters), this is just so components don't get damaged by sags, and come back for warranty repair.

The average factory head unit is going to produce around 5-10W per channel. A 500W Monsoon/etc sound system, is referring to 500W peak. (Trivia: Monsoon started out doing flat panel - planar - speakers, becoming popular amongst computer gamers in the 90's, before edging in on Bose's turf in the factory car audio scene.) A 50Wx4 aftermarket head unit is still only pushing 15-20W per channel. Not to say it can't do 50W per channel, rather, the results would be underwhelming and short-lived.

When you put in an amp, say, a JL 300/4, and assuming it's rated accurately, then you're actually pushing close to 300W at full load. But, the amp is going to draw more wattage than that. Class D (subwoofer) amps are the most efficient, but class AB amps (typical for full-range speakers) are only around 35-55% efficient. So to produce 300W, they're drawing around 600-800W.

Watts = Volts x Amps. Amps = Watts / Volts. 800W / 13.8 = 57 Amps. Look at your fuses; that's a pretty big chunk, the engineers didn't build into the design.

Now here's my rule of thumb. If you wire your entire stereo thru the existing fusebox, and you're not blowing fuses, you're probably fine. But if you start adding your own wiring (and adding in-line fuses, right?), you're exceeding the design of the factory wiring. At this point, you can add a cap, and it may hide the obvious symptoms. But now you're relying on a band-aid, rather than having fixed the real problem. And as the cap starts to degrade over time, the symptoms are going to re-apppear. But before you see your headlights dimming, you're going to have other electrical components complaining. Probably in the form of them frying, and necessitating repairs.

If the solution was to replace all the wiring in the car, we'd all say, screw that, it makes sense to use a cap, unless this is a competition vehicle. But really, the reason the wiring upgrade is suggested, is it shouldn't be that hard, or that expensive, and may even improve the performance of your vehicle.*

And,, now for the final part. Your positive side wiring is like a straw, and you can suck more juice thru the straw, if you try hard enough. You'll heat the wiring up, as the resistance goes up, but it'll work. But without a good ground, you're impeding the flow of that electricity, and that will become an issue. Spend some time around electrical troubleshooting, and you'll hear "bad ground" mentioned a lot. It's the principle on which the "Circle Earth" grounding kits, etc., are advertised. Well, do the Big 3, don't spend the money on an overhyped 'kit', and hopefully not even need a cap.


Now, all that said, every stereo shop out there will continue to be happy to install a cap for you. Most will even recommend it. Why? They don't want to do wiring upgrades, unless they have a product they can sell you. This isn't because they're ****s, it's because they are in business to make money. Their labor rates are only half of how they make their profit; the other half is markup on products, and there's few items that have as much markup as wiring kits.

And on the topic of wiring. You can spend thousands of dollars on wiring. If it makes you feel better, do it. Audiophiles drop a grand on a pair of 1-meter (3') speaker cables all the time. I've also seen high-end speaker designers use cheap $3 radio shack RCA patch cables between the Harmon Kardon source, and their high-end amp/crossover (driving the $6000 speakers they built.) Making sure the wire is of sufficient gauge is the #1 thing. Ensuring it's shielded when it needs to be, and otherwise kept isolated from interference (signal and power on separate sides, cross at 90 degrees if you have to) is #2. Soldering connections instead of using crimp-on connectors is #3. Using a particular brand of wiring kit, doesn't really make my list. Use lamp cord if you want, works fine. I'd put cash down, to say that you couldn't tell the difference, in a blind test, if both wires are properly sized.

Okay, maybe that's a nickel's worth, but figured adding some solid information, with explanations, was worthwhile to the sticky.

* Improvement of performance will occur when existing wiring was insufficient for overall electrical demands, on a transient (temporary) or constant basis. If the factory wiring was insufficient, baseline performance will be improved.. Don't expect butt dyno gains. Unless you rode in your friend's G35/300C/etc. after he did a grounding kit, and could totally feel an increased smoothness in the auto trans shifting. In which case, you'll definitely feel the power. It's like two bottles of naws, mang.
 

Last edited by macker; Aug 20, 2009 at 01:23 PM. Reason: Grammatical corrections to post-note
Old Aug 23, 2009 | 06:07 PM
  #37  
cashondelivery's Avatar
Joined: Jul 2009
Posts: 9
From: 407 to 813
Default

Originally Posted by macker
Short version: The cap is always a band-aid, but sometimes it's the most practical, in very high-wattage systems. There's benefits to doing a Big 3 upgrade, more than just not seeing your headlights dim, it's cheap, and it doesn't burn out over time like a cap does. If running a cap makes you feel better, do it, a properly functioning cap wont make anything worse. But a wiring upgrade may solve the problem, including some you didn't know you had.

Long version:

Eh, may as well add two more cents.

Car electrical equipment is designed to run in a voltage range, ~10-14V, 12V nominal, but really it wants 13.8V, which is what you should typically see on a car with a properly operating charging system, while the engine is running. Under heavy current draws, you'll see the voltage drop (sag). As a temporary condition, equipment will live, but it's never happy about it, particularly when it fluctuates frequently.

The reason for this is under heavy current pull, the resistance on the wire is going to start going up, reducing the capacity of the wire to flow current. This problem is exaggerated by the low voltage that cars operate on; high voltage "flows better", which is why the utility company flows at 30-100kV, stepping down as they get closer to your house, with 120/240V service for residential, or 480/600V for commercial.

Now if your sub is causing brownouts (just like a house light-bulb going dim when a big electrical appliance kicks on), then a cap may be an answer. It's certainly a cheaper and simpler alternative than running two batteries and an HO alternator. But, the better question is, what's the weakest link?

The 'Big 3' were sized for the cars original electrical system, assuming all factory options are installed, and may have a ~20% overhead in rating. This isn't so you can add accessories (other than cig lighter adapters), this is just so components don't get damaged by sags, and come back for warranty repair.

The average factory head unit is going to produce around 5-10W per channel. A 500W Monsoon/etc sound system, is referring to 500W peak. (Trivia: Monsoon started out doing flat panel - planar - speakers, becoming popular amongst computer gamers in the 90's, before edging in on Bose's turf in the factory car audio scene.) A 50Wx4 aftermarket head unit is still only pushing 15-20W per channel. Not to say it can't do 50W per channel, rather, the results would be underwhelming and short-lived.

When you put in an amp, say, a JL 300/4, and assuming it's rated accurately, then you're actually pushing close to 300W at full load. But, the amp is going to draw more wattage than that. Class D (subwoofer) amps are the most efficient, but class AB amps (typical for full-range speakers) are only around 35-55% efficient. So to produce 300W, they're drawing around 600-800W.

Watts = Volts x Amps. Amps = Watts / Volts. 800W / 13.8 = 57 Amps. Look at your fuses; that's a pretty big chunk, the engineers didn't build into the design.

Now here's my rule of thumb. If you wire your entire stereo thru the existing fusebox, and you're not blowing fuses, you're probably fine. But if you start adding your own wiring (and adding in-line fuses, right?), you're exceeding the design of the factory wiring. At this point, you can add a cap, and it may hide the obvious symptoms. But now you're relying on a band-aid, rather than having fixed the real problem. And as the cap starts to degrade over time, the symptoms are going to re-apppear. But before you see your headlights dimming, you're going to have other electrical components complaining. Probably in the form of them frying, and necessitating repairs.

If the solution was to replace all the wiring in the car, we'd all say, screw that, it makes sense to use a cap, unless this is a competition vehicle. But really, the reason the wiring upgrade is suggested, is it shouldn't be that hard, or that expensive, and may even improve the performance of your vehicle.*

And,, now for the final part. Your positive side wiring is like a straw, and you can suck more juice thru the straw, if you try hard enough. You'll heat the wiring up, as the resistance goes up, but it'll work. But without a good ground, you're impeding the flow of that electricity, and that will become an issue. Spend some time around electrical troubleshooting, and you'll hear "bad ground" mentioned a lot. It's the principle on which the "Circle Earth" grounding kits, etc., are advertised. Well, do the Big 3, don't spend the money on an overhyped 'kit', and hopefully not even need a cap.


Now, all that said, every stereo shop out there will continue to be happy to install a cap for you. Most will even recommend it. Why? They don't want to do wiring upgrades, unless they have a product they can sell you. This isn't because they're ****s, it's because they are in business to make money. Their labor rates are only half of how they make their profit; the other half is markup on products, and there's few items that have as much markup as wiring kits.

And on the topic of wiring. You can spend thousands of dollars on wiring. If it makes you feel better, do it. Audiophiles drop a grand on a pair of 1-meter (3') speaker cables all the time. I've also seen high-end speaker designers use cheap $3 radio shack RCA patch cables between the Harmon Kardon source, and their high-end amp/crossover (driving the $6000 speakers they built.) Making sure the wire is of sufficient gauge is the #1 thing. Ensuring it's shielded when it needs to be, and otherwise kept isolated from interference (signal and power on separate sides, cross at 90 degrees if you have to) is #2. Soldering connections instead of using crimp-on connectors is #3. Using a particular brand of wiring kit, doesn't really make my list. Use lamp cord if you want, works fine. I'd put cash down, to say that you couldn't tell the difference, in a blind test, if both wires are properly sized.

Okay, maybe that's a nickel's worth, but figured adding some solid information, with explanations, was worthwhile to the sticky.

* Improvement of performance will occur when existing wiring was insufficient for overall electrical demands, on a transient (temporary) or constant basis. If the factory wiring was insufficient, baseline performance will be improved.. Don't expect butt dyno gains. Unless you rode in your friend's G35/300C/etc. after he did a grounding kit, and could totally feel an increased smoothness in the auto trans shifting. In which case, you'll definitely feel the power. It's like two bottles of naws, mang.
****stands up and applauds****
 

Last edited by cashondelivery; Aug 23, 2009 at 06:09 PM.
Old Sep 30, 2009 | 08:35 PM
  #38  
Carl Dan's Avatar
1st Gear Member
Joined: Jul 2009
Posts: 116
Default

Originally Posted by sschic
Another simple fix for dimming headlamps is to purchase a capacitor and run it inline with your power wire to your amplifier for the subs. It will store up energy when the subs aren't running at full bore and release it when you need some major "thud". Make sure to install it within a few feet of your amplifier, the closer the better. A new alternator and battery can help prevent this from becoming a more serious problem, but if you are running a pretty serious system you NEED a capacitor. Here's a link:

http://www.google.com/products/catal...691#ps-sellers

I've been installing Car audio, Video, Navigation and Remote start systems for over 6 years and am MECP certified at Advanced level currently and i agree with a previous post that the Big three is a primary start with fixing Dimming a good electrical system is a happy one and more flow of power will help when adding a system to a car. Caps are all well and good but are more show and less go. A Big three upgrade, New upgraded battery or adding a second battery or a high amp alternator would be most ideal in the given situation of increased electrical demand.
 
Old Sep 30, 2009 | 08:41 PM
  #39  
Carl Dan's Avatar
1st Gear Member
Joined: Jul 2009
Posts: 116
Default

also somone who thinks you run a Cap "inline" is retarded. Cap's and additional batteries are ran in parallel not series and are a waste of money...unless you like to waste money on useless upgrades.
 
Old Oct 7, 2009 | 12:59 PM
  #40  
CaseyK's Avatar
Newbie
Joined: Oct 2009
Posts: 13
From: California
Default

hahah hiss, the question working cracked me up. good stuff man. and good info in here. catch you on the flip hissbaby
 



All times are GMT -5. The time now is 04:44 AM.