I did post this on the audio section and no replies this why I'm reposting here going for answers.
Ok, I have a Kenwood ddx690 with a Kenwood 1000 watt amp for a 10 jl audio corner sub. I have been noticing that my lights have been flickering a bit when the bass kicks. I am also looking into replacing my car battery. Should I use a capacitor for my set up. I have heard cons about capacitors draining batteries. I really need the communities help regarding my issues.

this is the amp that I'm using for my jl audio sub.
http://www.crutchfield.com/S-jGHs9xbKCQw/p_113KAC5001/Kenwood-KAC-5001PS.html


Thank you in advance.

 

Here's some info on them. I use a 700w amp and don't have any issues. Maybe the more power would require it.
http://www.crutchfield.com/S-7t4nP1s...itors/faq.html

 

I had a 1000 watt rms amp in a Cadillac I used to own. Needless to say it had major dimming issues. I put a 2 farad cap in it and it did noticeably help reduce the dimming, but the issue was still there. It never drained my battery. I ended up downsizing my system to 600 watts because I did not want to go the higher amp alternator route.

Caps are cheap enough to try out, give it a shot. Also, upgrading your chassis grounds will help and isn't too expensive either.

 

In DC circuits, capacitors block DC and pass AC, and typically act as noise filters. Since we are talking about voice frequencies here, I don't know if just adding a capacitor is going to solve your problem. A 700w amp is pretty serious power for a cabin the size of the Corvette.

 

I am dumber than a box of rocks on this subject! But any audio questions I have had in the past have always been answered by Dennis at DD Mods. He sold me and hundreds of guys in this forum our Kenwood units.

 

Heavy gauge wire directly from the amp to the battery, both + and - will make a difference also, because the battery will act as a very large capacitor.

 

So your saying to ground it to the negative battery post?

 

Absolutely and with big wire.

 

seems like $100 is cheap insurance.

 

 

Put that 100 towards a high output alternator. No shop worth thier salt will use caps. Ask any high end audio shop.

 

If anyone wants to know a little more about capacitors, and how they might make a difference, here is an excerpt from an article I wrote 10 years ago.

Garry

Adding Capacitors to Your System

For this issue I thought it would be a good time to review a much misunderstood and much maligned topic, the good old external power supply capacitor, or “Stiffening Cap™”. I like the term “stiffening” as that’s exactly what happens, the added current available in the capacitor “stiffens” the supply of current to the amplifier. (the term “Stiffening Capacitor” is a registered trademark of Autosound 2000, and used with kind permission)

Some people will tell you these things are snake oil, and many others swear by them. I have seen the subject of large storage capacitors take up several pages of internet postings, with supporters and detractors split about evenly. I think that much of the confusion that seems to surround capacitors is caused by two things. First, a fundamental misunderstanding of how they work and what their actual benefits are, and are not, and second, the amount of substandard, low quality product available at bargain prices that simply doesn’t work and is a waste of money. While high quality caps work well, poor caps can actually make things worse. And unfortunately, it’s difficult to know which are which. Before buying a capacitor, I would always do some research and consider the opinions of others who have used the brand and model before, as well as referencing test reports etc. Usually (but not always) the established brands are generally a safe bet. Price can also be a guide, as with most high performance parts, the cheapest brands are probably not the best performers.

These devices are not new. Dating back to the 1700’s when they were called Leyden jars, through the early 1900’s when they were referred to as condensers, the electrolytic capacitor is basically a device capable of storing electrical energy. How much energy can be stored, depends on the rating of the capacitor in microfarads, (or in the case of big caps in Farads), and the working voltage it’s designed to operate at. Now, getting back to car audio, the energy storage device in a car is the battery. The battery is designed to store enough energy to start the car, at which point the cars alternator becomes the main power source, because it provides a higher voltage potential. In a battery, there are typically a bunch of lead-oxide plates immersed in acid. The resultant chemical reaction creates an electrical charge potential or voltage in the battery. However, batteries have fairly high internal resistance, which explains why a charging voltage of over 14 volts is required to maintain a 12 volt battery. An electrolytic capacitor has far greater “plate area” than a typical battery, and as a result has much lower internal resistance. This allows much faster current delivery, without the voltage drop that’s attributed the batteries high internal resistance.

A car stereo amplifier has a switching power supply inside that does not consume power steadily like a light bulb or heating element. Instead, the power supply of a normal car amplifier draws current from the cars electrical system in very rapid pulses, usually in excess of 35,000 times per second. This means that your amplifier needs 35,000 pulses of current per second to reproduce your tunes… Think about that the next time you’re cruising down the street with the tunes cranked! Here’s where things get interesting. Suppose you had a device that was capable of supplying hundreds of amperes of current in milliseconds. To accomplish this, it would have to have very low internal resistance and inductance. These specs are referred to as ESR and ESL. Equivalent Series Resistance is usually measured in milliohms, and should be very low if the capacitor is going to be able to work properly. If you connected this device in parallel with the cars battery, and mounted it close to the amplifier to minimize wiring resistance losses, the amplifier would be able to draw all the current it needed, virtually instantly. And that, is exactly what a “Stiffening Cap™” does.

Okay, here’s where the confusion seems to start. Most high power amplifiers already contain a certain amount of power supply capacitance, but very few actually have enough to supply the power supply under all conditions. Adding that much internal capacitance would cost a lot of money, as well as make amplifiers quite a bit larger. However, back in the 80’s and 90’s I used to make a bit of spending money by upgrading the power supplies in old Fosgate, Linear Power, Phoenix Gold, and Audiomobile amplifiers. These mods absolutely made audible and measurable differences. As with my old modifications, the real and main benefit to using a “Stiffening Cap™” is improved sound quality, particularly in brief, high current transients, such as drums and plucked strings. As I mentioned above, if you have a big enough capacitor, (or a small enough amp) you may notice a reduction in the amount of headlight dimming to see when the bass notes hit as well.

Some people say that amplifiers using a “tightly” regulated power supply, can’t benefit from a Stiffening Capacitor™. That statement is simply nonsensical. Even highly regulated amplifiers still draw current in high frequency pulses, and if the supply of current upstream of the amplifier is too slow, the amplifier will not be able to obtain all the current it needs to reproduce the music properly. Remember, the main function of the Stiffening Cap™ is to provide very large amounts of current to the amplifier, in a very short period of time. They are not designed to hold the vehicles voltage up at a higher potential, although that can sometimes be an ancillary minor benefit.

Other people say that Stiffening Caps™ are useless in SPL contest vehicles. Again, I would fundamentally disagree. In fact, way back in 1983, Mr. dB Drag Racing himself, Wayne Harris, used a large bank of capacitors in his first National Crank-It-Up winning entry. Back then, Wayne had to cobble together dozens of smaller value caps to get the total amount of energy storage that you can buy today in a single package, but it was worth it, he won.

Still others claim they spent a bunch of money and were not able to hear or measure any difference whatsoever. Unfortunately, that is very possible. When these devices were first offered to the car audio industry, they gained wide acceptance and popularity. As with all things, the desire to make a profit reared its head, and in an effort to make a buck, some ahem, “less than optimum” product has been produced. But, quality products do exist, and they do work! One way to find a quality product is to ask others about what works and doesn’t work for them. Here is an example of one that didn't work well... This was sold as a 2 Farad capacitor!!

 

Awesome write-up Gary

Thank u

Dave

 

The stock alternator is barely enough output on a stock car. (especially if you have an underdrive pulley.)

Get a billet tech alternator instead.

 

I run a 1.5 farad cap w/2 400w Infinity amps in my 03 GP, it pretty much eliminated the "dimming" during bass heavy tracks. As a side benefit, it also eliminated most of the alternator "whine' from the system.

 

+1 on the wire upgrade to the battery.

 

Can you please elaborate on big wire. What gauge would be recommended?

 

You want 4 gauge wire. It's about the diameter of a pencil. Big wire.

You can buy it with terminal lugs already installed, or crimp on terminal lugs and run a ground wire directly to your battery's negative post.

https://www.amazon.com/Gauge-BLACK-A.../dp/B00L9CB6WE

 

Do an alternator, big 4 and be done. I'm going with a 200+ alt since I will be at 1920w when it's complete.

 

Thank you for the info! 😃