capacitor car audio

What's a capacitor? What they vì thế and when lớn use one

Q: What's a capacitor?

A: A capacitor, or cap, is an electronic component that can take up, store, and discharge electrical energy. Because they can vì thế all that quickly, capacitors are used lớn filter or buffer any sudden changes in a circuit's voltage, smoothing the ensuing signal.

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Q: What's a capacitor used for?

A: In siêu xe audio, large outboard capacitors, sometimes called stiffening caps, are used lớn prevent lights from dimming when loud bass notes play. They accomplish this by supplying the amplifier with a quick jolt of power.

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Q: Even if my lights don't dim, won't a capacitor still improve my system's low over response and overall sound?

A: Not really. A cap prevents the sound from deteriorating due lớn under-voltage, but doesn't actually improve the sound. It supports the amplifier by feeding it the power it needs for short bursts. So, while not improving sound quality directly, a cap does make it easier for the amp lớn perform its best.

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Q: What size capacitor should I get?

A: The rule of thumb is lớn put in 1 Farad of capacitance for every 1,000 watts RMS of total system power. But there is no electronic penalty for using larger value caps, and in fact, many see benefits with 2 or 3 Farads per 1,000 watts RMS. The larger the cap, the more charge is available for the amp when it needs it.

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Q: How vì thế I hook up a capacitor?

A: If you don't have the instructions that came with your capacitor, you should know first off that a cap can be dangerous. It can charge and discharge sánh much power sánh very quickly that it can weld metal objects, lượt thích tools and jewelry, and melt its own insides out.

A new cap comes completely discharged, sánh it's safe. A resistor or wired light bulb usually is included in the package. Wiring the bulb or resister across the cap's terminals allows the capacitor lớn discharge slowly and safely. The same bulb or resistor, wired differently, also gets used lớn charge up the cap safely.

As in all siêu xe electronic installations, start by disconnecting the ground cable from the siêu xe battery. In this installation, also take out the in-line fuse on the amp's power wire next lớn the battery.

A capacitor should be mounted as close lớn the sub amp as possible using the shortest wires possible. This is sánh the extra charge doesn't have far lớn go lớn get lớn the amp quickly. Make sure the cap gets mounted securely and won't become a dangerous flying object in the sự kiện of an accident.

A capacitor has two poles: a positive and a negative. They should be clearly marked on the capacitor. The positive connects lớn the same positive power lead that goes lớn your sub amp's positive, 12 volt, connection. Use the same gauge wire as the amp uses for its power. This can be accomplished with a distribution block. Or, sometimes, the cap comes with multiple connection terminals that make it easier lớn wire it into your system. The multiple terminals act just lượt thích a distribution block sánh, for instance, the power wire coming from your battery can connect directly lớn the cap's positive terminal while a short cable connects from there lớn the amp's positive power connection. The negative pole of the capacitor connects lớn your chassis ground, just lượt thích the amp. The best practice is lớn use the same bolt the amp uses for ground. Make sure all the paint is scraped off around where you put the chassis ground and the connections are clean and tight.

Next, you need lớn charge up your capacitor. If done too quickly — it could "pop," destroying the cap.

If you don't have the original charging/discharging resistor or light, you'll need lớn get one. An automotive 12-volt test light, the kind with a bulb, not a small LED, will vì thế nicely. Otherwise, you can use a high-wattage, low resistance resistor, available at most electronics parts stores. The exact value doesn't matter, but get one with a value of 10-1,000 ohms along with a rating of 1-20 watts. The lower the resistance, the higher the wattage should be.

Take the test light or resistor and connect it lớn the two terminals of the amp's in-line fuse holder (where you took the fuse out earlier). Re-connect the siêu xe battery's ground cable. The resistor will get hot, or the bulb will light up, while the cap charges. After 10 lớn 30 minutes, the bulb will fade out, or the resistor will start lớn cool. Remove the light or resistor carefully — they can get very hot. As you replace the fuse, you may experience a small spark — that's okay, but should remind you of how powerful the electric forces involved are. Your capacitor is now installed.

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Q: My capacitor has a third terminal. What's that for?

A: Some caps come with a built-in meter that displays the voltage. If a meter were lớn stay on constantly, it could drain the car's battery. So caps with meters often have a remote turn-on lead connection, just lượt thích siêu xe amplifiers, sánh the meter turns off with the system. A thin, 18-ga. or sánh, wire should lập cập from the cap's turn-on connection lớn the amplifier's remote turn-on terminal, or any other switched 12 volt power source.

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