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1,2,3 and to the 4ohm
November 5th 06, 03:58 AM
I just bought a used rockford cap from a friend for $5, I think its a 1
farad but dont know all the lables and markings are worn off. The
person I bought it from says he tested it and it works fine, I HAVE NO
IDEA!! I've never used one of these in my system and would like to know
the proper way to hook one up without blowin myself up. I'm pretty
sure its as simple as hookin up an amp, but i'd like to be sure, i dont
wont to start my car on fire or anything. I have a small amp in my
house hooked up to a power converter, just to test subs and other car
electronics, I was planning on testing it on that before hooking it up
to the nice system in the car. Also, some people on this site say that
you should "charge" the cap before hooking it up, is this true or BS.
Thanks for any help

02 civic Si
pioneer DEH-P680MP
Directed 600D
(2) Audiobahn AW-1200
RF 1 farad cap?
knowing that your audiobahns will blow away JL's, PRICELESS" :)

bassman07
November 5th 06, 05:00 AM
yes you should charge it. just prevents from arching and leaving a mark.
and as far as hooking it up, ground it first. then charge with diode or
bulb, then hook power up, then run power from cap to amp and run ground
from cap to amp. that simple.


--
bassman07

1,2,3 and to the 4ohm
November 5th 06, 05:05 AM
and how do you go about charging it??
thanks

bassman07
November 5th 06, 05:19 AM
if he didnt include a chargring bulb then you can you a diode. or you
can just stick the pwer wire on it. it makes no difference. the
diode/charging bulb doenst matter, all it does is prevent an arc and
putting a mark on your cap. given its used, it prolly shouldnt matter
unless you are like showing it off or something.


--
bassman07

1,2,3 and to the 4ohm
November 5th 06, 05:41 AM
thats cool, as i mentioned above, its old and used so all the
'niceness" of it is worn away anyways, now this arc your talking about,
is it a BIG arc, and what is the best way to tell if it is workin,
right now that amp i have in my house cuts in and out when pushed, i
figure its the low amperage of the power converter i'm using, should
putting the cap on it reduce this?

thanks again

John
November 5th 06, 05:53 AM
All you'd have to do is use any plan old 12v bulb of sorts in
replacement of the one normally supplied. Connect a piece of wire to
each of two parts of the bulb, connect one wire to the power cable and
the other to the cap.

Easiest way is to remove the ground from your battery, connect the cap
like you are supposed to, and then just reconnect your bat ground.


--
John

Matt Ion
November 5th 06, 07:40 PM
Uhh, okay, some pretty scary "advice" here...

First of all, you say the markings are worn off... are there any polarity
(plus/minus) markings? If you hook the cap up backward, it'll very likely blow
up (no, I'm not exaggerating). If you need to determine the polarity, there
should be enough juice left in it to at least give you a reading on a
multimeter. The "minus" terminal connects to ground, the "plus" to power.

Second, when charging it, DO NOT simply connect a wire OR A DIODE - it's
initially going to appear to the power source as a direct short, and will blow
up most any diode you use, and potentially melt or at least severely heat up the
wire. USE THE LIGHT BULB as John described. It will limit the current,
allowing the cap to charge safely, and when the bulb goes out, you know it's
charged.

After it's charged, BE VERY CAREFUL NO TO TOUCH BOTH TERMINALS, and don't let
any tools short across them. The point of using a cap in a stereo system is
that it can discharge large amounts of energy much faster than a battery - if
you've ever seen what happens when you short a battery with a wrench, just
imagine the same thing, only with a BIGGER spark

All that said, I really don't think your system will benefit noticeably from a
cap, especially if it's wired properly (sufficient gauge power wire). It may be
a neat thing to add as an experiment, but before you do that, I'd strongly
recommend looking up some articles on properly installing it - you have the
potential here to seriously burn yourself and/or your car.

Start here:
http://www.caraudiohelp.com/car_audio_capacitor_installation/car_audio_capacitor_installation.htm



1,2,3 and to the 4ohm wrote:
> I just bought a used rockford cap from a friend for $5, I think its a 1
> farad but dont know all the lables and markings are worn off. The
> person I bought it from says he tested it and it works fine, I HAVE NO
> IDEA!! I've never used one of these in my system and would like to know
> the proper way to hook one up without blowin myself up. I'm pretty
> sure its as simple as hookin up an amp, but i'd like to be sure, i dont
> wont to start my car on fire or anything. I have a small amp in my
> house hooked up to a power converter, just to test subs and other car
> electronics, I was planning on testing it on that before hooking it up
> to the nice system in the car. Also, some people on this site say that
> you should "charge" the cap before hooking it up, is this true or BS.
> Thanks for any help
>
> 02 civic Si
> pioneer DEH-P680MP
> Directed 600D
> (2) Audiobahn AW-1200
> RF 1 farad cap?
> knowing that your audiobahns will blow away JL's, PRICELESS" :)
>

John
November 5th 06, 09:09 PM
One thing to watch out for is -any- type of leakage, corrosion, or other
unusual things around the terminals...this will happen with- some- old
caps especially...depends on the components...


--
John

1,2,3 and to the 4ohm
November 10th 06, 05:05 AM
ok, thanks for the advice. and the cap isnt so old to where you cannot
read the polarity on the top, those are clearly readable, its just the
logos and all the "fancy" crap has worn off. and i really doubt that i
would benefit much from this as well, maybe gain a couple dB but when
your pushing 140+, 1 or 2 isnt going to be an audible difference

John
November 10th 06, 01:49 PM
I hope you weren't serious about the dB gain...because you are not going
to gain any decibels by adding a cap...you may even lose some...it is
possible in some installs, but not yours, not with this cap, but anyone
that guarantees you anything different doesn't understand the mechanics
of it or is ignorant.


--
John

D.Kreft
November 11th 06, 07:41 AM
On Nov 10, 5:49 am, John >
wrote:

> I hope you weren't serious about the dB gain...because you are not going
> to gain any decibels by adding a cap...you may even lose some...it is
> possible in some installs, but not yours, not with this cap, but anyone
> that guarantees you anything different doesn't understand the mechanics
> of it or is ignorant.

Okay, I have to bite...

Could you explain how one would lose SPL by adding a power supply
"stiffening" capacitor?

Actually, while I've got your ear (eye?), I'm equally interested in
finding out how one might experience a boost in SPL output through the
addition of such a capacitor.

-dan

Matt Ion
November 11th 06, 09:25 AM
D.Kreft wrote:
> On Nov 10, 5:49 am, John >
> wrote:
>
>
>>I hope you weren't serious about the dB gain...because you are not going
>>to gain any decibels by adding a cap...you may even lose some...it is
>>possible in some installs, but not yours, not with this cap, but anyone
>>that guarantees you anything different doesn't understand the mechanics
>>of it or is ignorant.
>
>
> Okay, I have to bite...
>
> Could you explain how one would lose SPL by adding a power supply
> "stiffening" capacitor?

I'm kinda curious about that one as well...

> Actually, while I've got your ear (eye?), I'm equally interested in
> finding out how one might experience a boost in SPL output through the
> addition of such a capacitor.

One wouldn't. One MAY not experience as much LOSS of output with the cap to
smooth out voltage drops... reducing losses isn't really the same thing as
gaining...

D.Kreft
November 11th 06, 06:25 PM
On Nov 11, 1:25 am, Matt Ion > wrote:

> One wouldn't.

C'mon, Matt...don't ruin it--I want to hear what John has to say about
this one.

> One MAY not experience as much LOSS of output with the cap to
> smooth out voltage drops... reducing losses isn't really the same thing as
> gaining...

Well, as long as the cat is out of the bag...

The voltage drops that are going to be smoothed-out are *transient*
drops, not sustained voltage sags. So, the correct answer here would be
that "transient response of the amplifier *may* be improved, and if the
amp has a regulated power supply it *may* also run a bit cooler since
the PS won't have to draw more current (and thus dissipate more heat)
as the voltage sags during particularly demanding transient passages."
The "problem" (for want of a better word) is that capacitors store a
very small amount of energy compared to a typical battery, but that's
okay because their intended purpose is to smooth out the amplifier's
input voltage, not somehow magically increase the amplifier's
capabilities.

With an amp having an unregulated power supply, the difference between
no cap and cap is going to be greater, but it's still not going to
result in a net change in any direction of average SPL.

-dan

bob wald
November 11th 06, 10:04 PM
look idot pay a installer $40 to put it in..god

KU40
November 11th 06, 11:03 PM
john gets his information from a good source, I've seen the test results
as well. I wish I could find the thread on CS.o that had it in it, but
I can't seem to find the right search words that point me to it.

wasn't it loyd who did that john? anyways, a guy did test his system
with and without a cap, and he lost a few tenths of a db with it.

I believe he attributed it to the car's charging system having to both
charge the cap and supply current to the amp once the capacitor is
initially discharged. the cap becomes a liability then. if your
electrical system is large enough to handle the overall current demand
by the amp(s), but just want to smooth out the spikes, they can do
that. but if after 2 minutes of playing your voltage is down to a
constant 12.5, a cap will be useless.


--
KU40

D.Kreft
November 12th 06, 12:01 AM
On Nov 11, 3:03 pm, KU40 >
wrote:

> wasn't it loyd who did that john? anyways, a guy did test his system
> with and without a cap, and he lost a few tenths of a db with it.

A few *tenths* of a dB SPL? Are you kidding me? That's like withdrawing
a cup of water from a swimming pool and saying "The water level in the
pool just went down." Sure it went down, but by such an insignificant
amount as to be completely immaterial!

Depending upon whose reasearch you look at, the minimum detectable
change in sound pressure level varies from 0.5 - 1.0 dB SPL
(http://www.audioholics.com/techtips/roomacoustics/HumanHearingAmplitude.php)
and no doubt these measurements were performed in an anechoic chamber.
Even if one lost, say, 0.5 dB SPL from the system, I'd be willing to
bet some paper money that in a typical automotive environment, one
would not be able to detect the difference.

>From a purely pragmatic point of view, there is no loss to be had when
adding a power supply "stiffening" cap in an automotive
system--insisting to the contrary is silly at best, and asinine at
worst.

> I believe he attributed it to the car's charging system having to both
> charge the cap and supply current to the amp once the capacitor is
> initially discharged. the cap becomes a liability then. if your
> electrical system is large enough to handle the overall current demand
> by the amp(s), but just want to smooth out the spikes, they can do
> that. but if after 2 minutes of playing your voltage is down to a
> constant 12.5, a cap will be useless.

Like I said already, the cap is for smoothing out *transient* voltage
sags, not boosting the steady-state voltage of your vehicle's
electrical system. Once a cap is charged, it acts as an open path to
ground (i.e. no current flows through it), so that is not a load on the
charging system, and even when the cap is *fully* discharged (and I'm
talking about a big 1F cap here), the charging time is virtually
instantaneous. But, the cap is never going to be fully discharged--the
battery would have to be completely dead for that to happen, and if
that's the case, the effect of the cap on the system is the least of
your concerns.

In the case you cite where your voltage hovers down near around a
steady 12.5 V, I wouldn't completely discount the benefits of having a
big cap on board, because it'll *still* even out voltage sags. A cap's
characteristics (i.e. its voltage response lag) aren't altered by a low
system voltage--the only difference is that your baseline voltage will
be lower and the amount of "headroom" that the cap will be able to
provide is also diminished.

In short, a big cap is not a panacea, but I think saying that it'd be
"useless" for the case you've cited is going a bit far; "compromised"
might be a better way to describe it, but certainly not "useless".

-dan

-dan

KU40
November 12th 06, 12:44 AM
D.Kreft Wrote:
> A few *tenths* of a dB SPL? Are you kidding me?
> -dan
I'm not kidding you, and I never said it would be noticeable to the
ear. I'll revert back to what John said about losing SPL comps by that
amount. I've seen it happen.

and at any rate, I would never use a cap in my system. the money is
much better spent on other upgrades, either a larger alternator or
battery. I'd much rather have a large battery with no cap than a small
battery with a cap trying to make up for it. sure money isn't really an
issue in this case because it was only 5 dollars, but.........the risk
of something bad happening goes up a little, especially since it's
used.


--
KU40

MOSFET
November 12th 06, 01:58 AM
> and at any rate, I would never use a cap in my system. the money is
> much better spent on other upgrades, either a larger alternator or
> battery.

A larger battery? I guess if you plan on listening with the engine off
quite a bit. Otherwise, a larger battery (or multiple batteries) will just
be an additional draw on your electrical system (when the engine is running)
and would actually lower your voltage. However, if you are talking about
upgrading to a yellow-top Optima, however, THAT IS a good move as they are
deep cycle (can be discharged and recharged over and over) and have a lower
internal resistance.

I do agree that if you had $300 to spend, it would make more sense to put in
a larger alternator than, say, a 20 Farad capacitor. A HO alternator is
almost always a better way to go if your goal is more bass producing
amperage.

However, I would disagree with the assertion that caps are useless and do
not make a difference. I use four farads in my system (using 5 separate
capacitors actually, one for each of my four amps and one next to my
battery). I DEFINITELY notice a difference with the caps vs. without the
caps, UP TO A POINT. Obviously, caps cannot produce current out of thin
air, but WITH the caps, I notice my headlights don't flicker, the bass seems
stronger, and the voltage stays rock-steady. But beyond a certain point,
the caps simply can't keep up and my voltage will drop like a stone.

But I do believe that caps can benefit certain systems. It all depends on
the demands you put on your system.

MOSFET

Matt Ion
November 12th 06, 02:17 AM
MOSFET wrote:
>>and at any rate, I would never use a cap in my system. the money is
>>much better spent on other upgrades, either a larger alternator or
>>battery.
>
>
> A larger battery? I guess if you plan on listening with the engine off
> quite a bit. Otherwise, a larger battery (or multiple batteries) will just
> be an additional draw on your electrical system (when the engine is running)
> and would actually lower your voltage. However, if you are talking about
> upgrading to a yellow-top Optima, however, THAT IS a good move as they are
> deep cycle (can be discharged and recharged over and over) and have a lower
> internal resistance.

Ultimately, a larger battery and/or cap should not IN THEMSELVES be a heavier
draw on the alternator *once they're charged*. If either is constantly
requiring charging current, it's because the electrical ACCESSORIES (amp(s) and
system included) are drawing more current than the alternator can supply, and
relying on the battery/cap for their energy demands.

> I do agree that if you had $300 to spend, it would make more sense to put in
> a larger alternator than, say, a 20 Farad capacitor. A HO alternator is
> almost always a better way to go if your goal is more bass producing
> amperage.

True!

> But I do believe that caps can benefit certain systems. It all depends on
> the demands you put on your system.

Agreed. Unfortunately they're used far too often for the wrong reasons...

MOSFET
November 12th 06, 09:07 PM
> Ultimately, a larger battery and/or cap should not IN THEMSELVES be a
heavier
> draw on the alternator *once they're charged*.

OK, Matt, you've touched on an issue I've always been a little unclear about
and maybe you can clarify.

My understanding has always been that EVEN A FULLY CHARGED battery will draw
SOME current because of the internal resistance of the battery (which is why
you must supply MORE than 12 volts to charge a 12 volt battery). That was
why I said what I did, that adding additional batteries would likely lower
your voltage (even if the batteries are fully charged) a little bit.

Am I wrong? If you take a fully charged battery and add it to your
electrical system, will it have no effect on voltage (granted the decrease
would be small, but a decrease none the less)?

If I'm wrong, then I suppose there would be no downside in filling your car
with batteries, right?

Again, I have always worked under the assumption that additional batteries
(even when fully charged) do draw some current (albeit not much).

Now capacitors are an ENTIRELY different story (as there is no internal
resistance). With caps, the more the merrier. In my book, there's no such
thing as too much capacitance.

MOSFET

Matt Ion
November 13th 06, 01:58 AM
MOSFET wrote:
>>Ultimately, a larger battery and/or cap should not IN THEMSELVES be a
>
> heavier
>
>>draw on the alternator *once they're charged*.
>
>
> OK, Matt, you've touched on an issue I've always been a little unclear about
> and maybe you can clarify.
>
> My understanding has always been that EVEN A FULLY CHARGED battery will draw
> SOME current because of the internal resistance of the battery (which is why
> you must supply MORE than 12 volts to charge a 12 volt battery). That was
> why I said what I did, that adding additional batteries would likely lower
> your voltage (even if the batteries are fully charged) a little bit.
>
> Am I wrong? If you take a fully charged battery and add it to your
> electrical system, will it have no effect on voltage (granted the decrease
> would be small, but a decrease none the less)?

It would likely draw a small amount of current, but no, there will be no
*ongoing* loss of voltage. Assuming your alternator and voltage regulator are
working properly, you'll see a slight drop any time a load is added - such as
turning on your lights - but the regulator should compensate for that and bring
it back up. Remember too that the voltage varies anyway - most cars run around
13.0-13.5V at idle, and this is enough to charge the battery.

> If I'm wrong, then I suppose there would be no downside in filling your car
> with batteries, right?

In theory, no. In practicality, they'd add a lot of extra weight, and you
wouldn't really want to put them INSIDE the car (production of hydrogen gas and
all that), so space would be limited.

> Again, I have always worked under the assumption that additional batteries
> (even when fully charged) do draw some current (albeit not much).

I don't KNOW that they do, but I would expect so (one day I may hook up an
ammeter and find out)... even then, it probably wouldn't be any more than a
marker light. Just turning on the radio would draw more, forget any amps. In
short, IF there's additional current draw, it's not enough to even think about,
let alone worry about.

> Now capacitors are an ENTIRELY different story (as there is no internal
> resistance). With caps, the more the merrier. In my book, there's no such
> thing as too much capacitance.

Well, except it's a lot of extra expense that most systems don't need.

John
November 13th 06, 03:31 AM
Not to mention, as far as current draw goes, how many caps have flashing
lights of some kind and voltmeters...bad design to boot as the voltmeter
cannot be accurate as it draws all of it's power from the very source it
is supposed to be monitoring...


--
John

Chris
November 16th 06, 04:22 PM
Matt Ion schrieb:

> Uhh, okay, some pretty scary "advice" here...
>
> First of all, you say the markings are worn off... are there any polarity
> (plus/minus) markings? If you hook the cap up backward, it'll very likely blow
> up (no, I'm not exaggerating). If you need to determine the polarity, there
> should be enough juice left in it to at least give you a reading on a
> multimeter. The "minus" terminal connects to ground, the "plus" to power.
>
> Second, when charging it, DO NOT simply connect a wire OR A DIODE - it's
> initially going to appear to the power source as a direct short, and will blow
> up most any diode you use, and potentially melt or at least severely heat up the
> wire. USE THE LIGHT BULB as John described. It will limit the current,
> allowing the cap to charge safely, and when the bulb goes out, you know it's
> charged.
>
> After it's charged, BE VERY CAREFUL NO TO TOUCH BOTH TERMINALS, and don't let
> any tools short across them. The point of using a cap in a stereo system is
> that it can discharge large amounts of energy much faster than a battery - if
> you've ever seen what happens when you short a battery with a wrench, just
> imagine the same thing, only with a BIGGER spark
>
> All that said, I really don't think your system will benefit noticeably from a
> cap, especially if it's wired properly (sufficient gauge power wire). It may be
> a neat thing to add as an experiment, but before you do that, I'd strongly
> recommend looking up some articles on properly installing it - you have the
> potential here to seriously burn yourself and/or your car.
>
> Start here:
> http://www.caraudiohelp.com/car_audio_capacitor_installation/car_audio_capacitor_installation.htm
>
>
>
> 1,2,3 and to the 4ohm wrote:
> > I just bought a used rockford cap from a friend for $5, I think its a 1
> > farad but dont know all the lables and markings are worn off. The
> > person I bought it from says he tested it and it works fine, I HAVE NO
> > IDEA!! I've never used one of these in my system and would like to know
> > the proper way to hook one up without blowin myself up. I'm pretty
> > sure its as simple as hookin up an amp, but i'd like to be sure, i dont
> > wont to start my car on fire or anything. I have a small amp in my
> > house hooked up to a power converter, just to test subs and other car
> > electronics, I was planning on testing it on that before hooking it up
> > to the nice system in the car. Also, some people on this site say that
> > you should "charge" the cap before hooking it up, is this true or BS.
> > Thanks for any help
> >
> > 02 civic Si
> > pioneer DEH-P680MP
> > Directed 600D
> > (2) Audiobahn AW-1200
> > RF 1 farad cap?
> > knowing that your audiobahns will blow away JL's, PRICELESS" :)
> >

Heelo

cool instaltions guide for power caps

http://www.powernetshop.at/rockford-fosgate-car-hifi-store-gesamt-programm/index.html

Matt Ion
November 16th 06, 06:08 PM
Chris wrote:
> Matt Ion schrieb:
>
>
>>Uhh, okay, some pretty scary "advice" here...
>>
>>First of all, you say the markings are worn off... are there any polarity
>>(plus/minus) markings? If you hook the cap up backward, it'll very likely blow
>>up (no, I'm not exaggerating). If you need to determine the polarity, there
>>should be enough juice left in it to at least give you a reading on a
>>multimeter. The "minus" terminal connects to ground, the "plus" to power.
>>
>>Second, when charging it, DO NOT simply connect a wire OR A DIODE - it's
>>initially going to appear to the power source as a direct short, and will blow
>>up most any diode you use, and potentially melt or at least severely heat up the
>>wire. USE THE LIGHT BULB as John described. It will limit the current,
>>allowing the cap to charge safely, and when the bulb goes out, you know it's
>>charged.
>>
>>After it's charged, BE VERY CAREFUL NO TO TOUCH BOTH TERMINALS, and don't let
>>any tools short across them. The point of using a cap in a stereo system is
>>that it can discharge large amounts of energy much faster than a battery - if
>>you've ever seen what happens when you short a battery with a wrench, just
>>imagine the same thing, only with a BIGGER spark
>>
>>All that said, I really don't think your system will benefit noticeably from a
>>cap, especially if it's wired properly (sufficient gauge power wire). It may be
>>a neat thing to add as an experiment, but before you do that, I'd strongly
>>recommend looking up some articles on properly installing it - you have the
>>potential here to seriously burn yourself and/or your car.
>>
>>Start here:
>>http://www.caraudiohelp.com/car_audio_capacitor_installation/car_audio_capacitor_installation.htm
>>
>>
>>
>>1,2,3 and to the 4ohm wrote:
>>
>>>I just bought a used rockford cap from a friend for $5, I think its a 1
>>>farad but dont know all the lables and markings are worn off. The
>>>person I bought it from says he tested it and it works fine, I HAVE NO
>>>IDEA!! I've never used one of these in my system and would like to know
>>>the proper way to hook one up without blowin myself up. I'm pretty
>>>sure its as simple as hookin up an amp, but i'd like to be sure, i dont
>>>wont to start my car on fire or anything. I have a small amp in my
>>>house hooked up to a power converter, just to test subs and other car
>>>electronics, I was planning on testing it on that before hooking it up
>>>to the nice system in the car. Also, some people on this site say that
>>>you should "charge" the cap before hooking it up, is this true or BS.
>>>Thanks for any help
>>>
>>>02 civic Si
>>>pioneer DEH-P680MP
>>>Directed 600D
>>>(2) Audiobahn AW-1200
>>>RF 1 farad cap?
>>>knowing that your audiobahns will blow away JL's, PRICELESS" :)
>>>
>
>
> Heelo
>
> cool instaltions guide for power caps
>
> http://www.powernetshop.at/rockford-fosgate-car-hifi-store-gesamt-programm/index.html

Ya, nice SPAM, ****er.

MOSFET
November 16th 06, 07:27 PM
> >
> > cool instaltions guide for power caps
> >
> >
http://www.powernetshop.at/rockford-fosgate-car-hifi-store-gesamt-programm/index.html
>
> Ya, nice SPAM, ****er.

Nice? It's all in German! German SPAM?

GregS
November 16th 06, 08:28 PM
In article >, "MOSFET" > wrote:
>> >
>> > cool instaltions guide for power caps
>> >
>> >
>http://www.powernetshop.at/rockford-fosgate-car-hifi-store-gesamt-programm/inde
>x.html
>>
>> Ya, nice SPAM, ****er.
>
>Nice? It's all in German! German SPAM?

And I type in MB an get nothing!

greg

D.Kreft
November 17th 06, 04:25 AM
On Nov 11, 2:04 pm, (bob wald) wrote:

> look idot pay a installer $40 to put it in..god

Ahh...webtv at its finest. In 10 years, nothing has changed.

When hurling geological specimens at great velocities, one must take
care not to do so from within fragile, transparent domiciles.

Besides, what has the Illinois Department of Transportation (IDOT) have
to do with anything?

-dan