Understanding The Basic Car Audio Capacitors

The audio system in our cars is an assortment of different parts. Each and every part in the system performs a specific function. It is with the co-ordination of all the parts, that you can hear the system play those fantastic tracks as you drive along. In the entire system, car audio capacitors have a significance of their own.

What are car audio capacitors?

Car audio capacitors are basically power storages in the car. These capacitors accumulate that power which is essential for the amplifier to produce great sounds. You can hear the booming bass sounds and songs with that much needed punch only because of audio capacitors. Car audio capacitors are also known as stiffening capacitors.

More on car audio capacitors

• Audio capacitors accumulate power whenever it is not required. This power is released when the demand for power exceeds the supply capacity of the power system of the car.

• Audio capacitors are necessary to supplement the regular power supply of the car in order to ensure the smooth functioning of the amplifier. Car audio capacitors usually range from 0.5 farads to 3 farads.

• You have to install a car audio capacitor that complements your amplifier. It is also necessary to place the capacitor as near as possible to the amplifier. For 500 RMS of power output, it is necessary to have an audio capacitor of 0.5 farads.

• There are also digital audio power capacitors. These can also be installed in cars. A digital audio capacitor (usually from 1.5 farads) consists of a turn on and turn off circuitry along with a 24-volt DC.

If you car lights dim when your car audio system produces a deep bass note, then your amp will be greatly helped with a car audio capacitor.

How do I know I need A Capacitor?

Before installation, it's often difficult to predict whether or not a capacitor will be beneficial to you. It's generally best to install the audio equipment prior to making the determination, so that you can address which symptoms need to be remedied and assess the severity of the symptoms. This will not only help you decide whether or not you need a capacitor, but also how much capacitance would be beneficial.

The most common symptom in need of added capacitance is headlight dimming (and sometimes dimming of the interior/dash lights). It's caused by a drop in system voltage associated with excessive current draw. While there may indeed be several loads drawing substantial amounts of current from the electrical system (eg. heat, AC, and so forth), it's usually the transient draws that best manifest themselves in noticeable dimming. This is partly because our visual systems are most sensitive to detecting rapidly changing intensity levels rather than steady absolute differences.

Once you've assessed whether or not the dimming is noticeable (and sufficiently annoying), you must decide whether a capacitor is warranted or if you'd be better served by upgrading the alternator.After initially having your alternator and battery checked out (some places will do this for free), the choice should be based on the severity of the dimming.

A commonly-used estimate for determining the appropriate size capacitor is 1F/kW (one farad per kilowatt). For example, a system running at300W would need a 0.3F (or 300,000uF) capacitor. However, there are several variables at play here, including the capabilities of the vehicle's electrical system (which generally varies from idle to higher RPMs), the efficiency of the amplifiers, and the listening habits of the user (ie. the tone controls and the type of music).

These factors should all be considered when making the determination. Moreover, the voltage drop can be so severe that added capacitance is nothing more than a band-aid. That is, even several Farads of capacitance would not be able to sustain the voltage for as long as the drop persists. This Is when an alternator upgrade may be in order.

How to wire a capacitor?

You can refer to a recent post on wiring Here

Planning Your Audio System

This part of the game can be fun or disappointing depending on what you can do. First I'm going to give you an example system that I believe includes everything you need to have a pretty good system. After that I will show you how to make compromises and leave out parts that may not be as important to you to keep your system within your budget. If you want to go beyond my basic system you probably already know more than what this site can tell you. Also, you do not have to get everything at once. I put my system together over a few years. With a little planning you can upgrade your system in steps and that way its like getting a new system every time you change something instead of getting everything at once!

Basic System: This is my opinion only but I think that a good system should start off with a good head unit that either has a CD player and/or is connected to a CD changer. A good system sounds best when playing CDs, tapes just do not cut it. Next I think component sets are made with fewer compromises than coaxial speakers so I suggest getting a good mid-range/tweeter set for the front. Head units generally do not put out enough clean power so you will want an amp to drive the component set. In the rear where you only need some "fill" for ambiance you can get away with cheaper coaxials and set their level lower than the fronts to keep the sound stage in front. A modest (50x4) 4 channel amp is a good choice here for powering the component set up front and the rear speakers. You could use a good 2 channel amp and run the front and back in parallel on the amp but it would harder to adjust the level between them. Mid-ranges sound best when they do not play bass so you will want a 2 way electronic crossover and use the high pass output to drive your 4 channel amp. I did not forget the bass! Most people are happy with a single 10" woofer or a pair of 12"s. Use an appropriate enclosure and a big amp (at least 75x2, preferably even more). Throw in installation and wiring accessories (like fuses and distribution blocks). Here's an approximate price break down of what this costs in my area. Your prices may be significantly different.

• head unit: $300-$500
  
• 4 channel amp for highs: $250-$400
  
• 2 channel amp for lows: $300-$700
  
• sub(s) (1-10" to 2-12"): $150-$450
  
• enclosure for sub(s): $0 (free air) - $250 (custom)
  
• component set: $200-$500
  
• coaxials for rear fill: $100-$400
  
• crossover/equalizer: $100-$500
  
• wiring and accessories: $50-$250
  
• installation: $0 (do it yourself) - $100 (basic)

This comes out to $1450-$3950! I realize that this is a lot of money and that most people do not spend nearly this much money on their car stereo. However, the things listed above are what I feel is necessary to have a system with only a few compromises. If you are less concerned about highs, get coaxials in front instead of the component set and power them off of the head unit and use some bass blockers on them. This will save you about $400. Getting a bargain head unit can save you some money as well. If you are really not into bass much you can forgo all the bass related equipment and run your component set full range. This will still give you clean sound but not much bass. However, you will save $550-$2300. I would start with what I have listed above and take out parts you do not care about as much. Only you know what kind of system you can be happy with.

Please do not email me asking for recommendations about specific brands. There is a lot of equipment out there that I have not used so I will not comment on them. I am happy with the components that I have but that is as far as I can go with recommendations. When buying equipment try to spend time listening to it before you buy, especially with speakers. Also try to use equipment that is similar to yours when listening in a store. As for amps, it costs money to build a good amp so if you see some awesome price on an amp you have never heard of, it is probably a piece of junk. Stick with good names with amps.

Finally, if you are on a budget (aren't we all?) it works better to upgrade in steps. The most important thing is to have a car audio system that sounds good to you not someone else. If you are happy with just changing the factory speakers and stopping there then just do that. There is a level when that new amp or speaker is not going to make a difference so it is not necessary to always upgrade. There are people who think my system is terrible but it works well enough for me and anything else I do to it would be a minor gain and not worth my trouble. Do not let a salesperson talk you into something you do not need! Good luck!