# How long do 1+ farad capacitors generally last?



## demoncamber (May 22, 2013)

Curious, as I cannot find the answer. How long does a 1+ farad capacitor generally last? How do you test if it's working 100%, when do you know it's failed? How do you properly test with a multimeter? Etc.


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## SkizeR (Apr 19, 2011)

long enough to know they dont do anything good. save your money and buy a small second battery if you need the extra power


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## Viggen (May 2, 2011)

Mine has been working flawlessly for 20 years now, purchased it back in I think 1993 or was it 1992 when I sold electronics. Been sitting of my shelf in my garage since probably 1995..... And will remain there until I give it away


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## IBcivic (Jan 6, 2009)

They make great paper weights for those days that you want to work with the shop doors open.


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## minbari (Mar 3, 2011)

SkizeR said:


> long enough to know they dont do anything good. save your money and buy a small second battery if you need the extra power


ha ha, they do have uses as a good noise filter if you have a noisey alternator, but that is about it.

as for longevity, as long as the magic smoke is not let out, they should last forever.


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## demoncamber (May 22, 2013)

cajunner said:


> I'm pretty sure there are several grades of caps and depending on whether or not one purchases a big aluminum can with a tiny cap inside or an actual huge cap with real stuffing the build quality is going to reflect the longevity of the cap.


Wow, thanks man, great info there.

While removing the cap, the negative terminal bolt snapped  and I did just buy another battery, so I'm thinking of just selling the cap as is.

HOWEVER, there's new testing that shows capacitors may actually live up to their claim, even as low as a 1 farad. Which if true should silence all debates on if they do anything at all. Look at this! 




All tests in this video were made using the Uncertified Dyno Mode which is a continuous sine wave. We test a Rockford T2500-1bdcp in car, with no added capacitors, then with a 1 Farad aluminum electrolytic capacitor added, and then with a 100 Farad carbon supercapacitor added.

RESULTS:
No Capacitor:
1499 Watts RMS @ 13.07V into 4 ohms
2059 Watts RMS @ 11.84V into 2 ohms
2366 Watts RMS @ 10.83V into 1 ohm

With 1 Farad Capacitor:
1489 Watts RMS @ 13.10V into 4 ohms
2024 Watts RMS @ 11.90V into 2 ohms
2358 Watts RMS @ 10.87V into 1 ohm

With 100 Farad carbon supercapacitor:
1531 Watts RMS @ 13.13V into 4 ohms
2208 Watts RMS @ 12.25V into 2 ohms
2606 Watts RMS @ 11.30V into 1 ohm

Engine RPM held between 2200-2500 for all tests.

1F capacitor didn't add any power on the continuous RMS test, actually lost a few watts probably due to the increased number of wire connections.

*100F capacitor added more than 10% more power on the continuous RMS test*

*THEN*
Same intro as Part 1, but dyno runs clips are changed to the dynamic power test clips

All tests in this video were made using the Dynamic Power (Burst) Dyno mode which is representative of musical peaks. We test a Rockford T2500-1bdcp in car, with no added capacitors, then with a 1 Farad aluminum electrolytic capacitor added, and then with a 100 Farad carbon supercapacitor added.

RESULTS:
No Capacitor:
1543 Watts RMS @ 13.80V into 4 ohms
2550 Watts RMS @ 13.32V into 2 ohms
3154 Watts RMS @ 12.76V into 1 ohm

With 1 Farad Capacitor:
1613 Watts RMS @ 13.98V into 4 ohms
2666 Watts RMS @ 13.60V into 2 ohms
3426 Watts RMS @ 13.35V into 1 ohm

With 100 Farad carbon supercapacitor:
1620 Watts RMS @ 13.95V into 4 ohms
2616 Watts RMS @ 13.65V into 2 ohms
3260 Watts RMS @ 12.91V into 1 ohm

Engine RPM held between 2200-2500 for all tests.

*1F capacitor didn't add any power on the continuous RMS test, but it OWNED the Dynamic Burst testing!!*

100F capacitor added more than 10% more power on the continuous RMS test, but less than 5% on the dynamic burst test.


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## Oliver (Jun 25, 2007)

I pulled over 9 capacitors out of my amp and the performance is incredible now.

Look for pics of amps inside and pull out all of the capacitors, they don't do **** but drain your battery :laugh:

*Engineers are dumb asses !!*


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## minbari (Mar 3, 2011)

I have to say, "so what?" you add a 100F cap to get 30 more watts? lets assume they are even right in the first place. who cares? 30 more watts from a 1500 watt amplifier is about 0.08db more. whoopie!

lets not forget the cost of a 100F cap to get that less than stellar increase.


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## D-Bass (Apr 27, 2012)

you can test capacitance value even if your DMM doesn't have a specific setting for it. a dmm, resistor, and a clock with a second hand


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## TrickyRicky (Apr 5, 2009)

SMD is a joke and most of us here know that. Uncertified ..... That should say it all....it's going to be a sad day when that machine gets certified, i can see it already...a bunch of teenagers stepping on the gas for test results.


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## ATOMICTECH62 (Jan 24, 2009)

The SMD clipping dector is a waste of money.We tested it on the bench and it detects clipping at about 40% distortion.They sell for almost $300.That will buy a good decent hand held scope and a crap load of test disc's.


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## demoncamber (May 22, 2013)

lol ^ well said.


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