Car Stereo Capacitors used for Amplifiers ?

[Switch Kit]

Was just wondering if or how one of these might be helpful behind a Texas Star DX500 in your vehicle ? What would I look for concerning the size I might need ? and how are they even hooked up ? The pros and cons if any . Sounds interesting and just was wondering if they could be of help . Thanks SK

 

[Shockwave]

Was just wondering if or how one of these might be helpful behind a Texas Star DX500 in your vehicle ? What would I look for concerning the size I might need ? and how are they even hooked up ? The pros and cons if any . Sounds interesting and just was wondering if they could be of help . Thanks SK

Unless you are using the amplifier on sideband, the answer is no. The capacitor is only beneficial for intermittent loads. The sustained load of a carrier on AM will defeat the purpose.

 

[Switch Kit]

Unless you are using the amplifier on sideband, the answer is no. The capacitor is only beneficial for intermittent loads. The sustained load of a carrier on AM will defeat the purpose.

It would be on sideband , could you recommend one ? Thanks Shock

 

[Shockwave]

It would be on sideband , could you recommend one ? Thanks Shock

It's been a long time since I've used one. Back then the goal used to be a one farad capacitor. Today that value is easy to achieve and I've seen many that are two farads. They typically have a maximum voltage of 15 or 16 volts and match a stock electrical voltage system well. The goal is to connect them close to the back of the power amplifier and in parallel with the positive and negative wires.

They compensate for voltage drop during brief peak demands. Such as bass thumps on a stereo amplifier or, word peaks on a sideband amplifier. Don't expect major improvements. You might be able to measure it on a watt meter.

 

[nomadradio]

It's a filter capacitor. It serves to smooth out voltage drops caused by loud bass notes in audio amplifiers.

The current draw running AM doesn't bounce up and down the same way, so extra filtering won't make a difference you can see or hear. Sideband does create radical fluctuations in the current drain that could cause voltage drops that a capacitor might help. And fatter wires would probably make the capacitor unnecessary.

Spending money on an improvement nobody on the listening end can hear is all very good, but I never recommend it to a paying customer.

73

 

[Switch Kit]

It's a filter capacitor. It serves to smooth out voltage drops caused by loud bass notes in audio amplifiers.

The current draw running AM doesn't bounce up and down the same way, so extra filtering won't make a difference you can see or hear. Sideband does create radical fluctuations in the current drain that could cause voltage drops that a capacitor might help. And fatter wires would probably make the capacitor unnecessary.

Spending money on an improvement nobody on the listening end can hear is all very good, but I never recommend it to a paying customer.

73

Thanks guys for the replies , my thought wasn't about getting more power out of the amp . I run about 6 feet of heavy 8 gage to my amp from the battery , I'm seeing a little dimming of my headlights at night when talking on SSB , I was just wondering if one of those caps might be of any help concerning the draw ? Old car that's had a lot of use with amplifiers over 20 years , 95 amp alt seems like she might be getting a little tired these days , I've heard others over the years talk of using those caps in there cars and off there power supplies at home . I don't do much night driving anyway just was wondering how significant those caps might be in the transmitting radio world . I suppose I could change over to 6 gage couldn't hurt . Thanks again gentlemen .

 

[9C1Driver]

Switch there is an old thread here on running bat caps from stereo shops here somewhere. As already stated the general consensus was it just didn’t accomplish much. In your case an upgrade to say a 140 amp alternator would be money and time better spent.

 

[Shadetree Mechanic]

A second battery will outperform a big capacitor in a car stereo system. Unless you have a bank of super caps, it's just a waste of money. And I agree with @9C1Driver, a bigger alternator is the most practical solution.

 

[Eldorado828]

The BIG 3 as it's known in the car audio world. Upgrade cables, alternator and batteries can apply to the radio world as well.

Every thread before this one is all facts so I won't be redundant.

In your case, even a smaller kinetik battery between you car battery and amplifier can make a difference in current/voltage drops. That alone can help stabilize things quite a bit.

Or the big 3 if you have the coin.

 

[Cable Guy]

I think the super caps were meant to be a band-aid, a sort of temp fix for issues caused by a weaker stock alternator and small gauge wire, particularly over a long run, such as an amp and sub installed in a trunk. I agree with the previous suggestions of larger alternator, sufficient gauge wire and battery.

 

[unit_399]

A "super" cap (1 Farad or larger ) is an excellent addition to any hi-power station (especially mobiles), as it provides additional reserve current under high amp draw conditions in SSB mode. Place the cap as close to the amplifier as posssible to eliminate losses in the power cables.

In mobile AM mode, connecting a Super Cap in parallel with the battery can partially negate the the reduction of battery power due to sulfate buildup on the battery plates and electrodes. Usually this buildup is removed as the battery is recharged. But over time some crystals remain and reduce battery output power (amps). This build-up causes the battery to be undercharged. If the standing voltage of a disconnected battery is less than 12.4 volts, it is not fully charged due to sulfacion, and can not deliver full power.

This sulfacion can be removed:

1. Drain the acid from the battery and neutralize it. Refill with distilled water to rinse it out. The drained acidic liquid can be neutralized by adding a small amount of baking soda.

2. Protect yourself by wearing safety glasses and gloves. This process involves handling acidic liquid and may result in serious injuries.

3. Measure 12-14 ounces of Epsom salts, and set them aside. Pour 1 quart of distilled water into a pan and heat it. The temperature should reach 150 degrees Fahrenheit.

4. Add Epsom salts to the hot water and wait for them to dissolve. Pour the mixture into the battery. Make sure the cells are completely filled.

5. Replace the caps and gently shake the battery. This will ensure even distribution on each cell. Now charge the battery.

6. Drain the salt liquid and rinse out the battery (twice) with distilled water.
Fill each cell with fresh battery acid. (Available at most auto parts stores).

7. Recharge the battery.

8. Reinstall the battery , making certain the terminals are clean and tight. Coat the terminals with grease as a moisture barrier

9. Once done, you’ll notice improved battery performance and station output.
*****************************************************************************

This procedure is a must, especially if your battery is 1-2 years old. If you use your station a lot, it should be done once a year. Sounds like a PITA, but we need every milliwatt of output that we can get. Right ??


- J.J. 399

 

[Switch Kit]

Thanks a lot for everyone's time on this one , much appreciated ! I guess in my situation concerning what I do have , knowing my own limitations can save my ass . I don't need anymore power just enough power to comfortably run what I have or down grade if I need to . Like I said , guys use those caps and as long as they are OK with them , so be it then. You all taught me something new here and although those caps don't cost much , I won't be going down that rabbit hole . I would agree with the upgrade of a new alternator or even bigger hook up wire , my car is old as is and the fact it's still running is a blessing in it self . Cheers to all you guys that know and have been there and done that. This is and has been the best darn radio forum on the internet as far as I'm concerned for a long time now and I'm glad to see it's still going strong after all these years and for all the help I've been given. (I just didn't know what I didn't know , I only thought I did. ) SK

 

[FlatlandBusa]

My current setup: AT6666, 8 pill, 240 amp custom alternator, AGM battery under the hood, 2/0 cables, 500farad cap bank at the amp,everything well grounded. The cap bank made a big difference in average voltage at amp, PEP watts came up by 200 and average went from around 30% to over 45%. For me a super cap is worth it when running anything over a 2 pill. Want evidence?? scope the battery voltage while talking SSB before and after the super cap. The little 1 farad stereo shop caps don't do anything.