Capacitor Information - Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums

strauchpete · 02-18-2010, 11:17 PM

After typing up a long response to everyone of you, I just said Its pointless,and deleted it. Getting rude emails from people I just decided to remove this thread.

I have been doing car audio for over 10 years now professionally and in this industry everyone from the 16 yr old kid to the old man that used 8track is a self proclaimed expert, so I said why bother. I am MECP Basic, Advanced, Sales and ASE Eletrical but hey who cares.

All I was trying to do is give some of the people that really dont know alot about car audio some BASIC insight into caps, and I so they dont get screwed by someone or waste there money on something that would not fix the problems they have.

thx to everyone, probably wont be seeing me that much anymore on here.

Sidewayz_510 · 02-23-2010, 04:22 AM

so do you recommend installing a capacitor if i wish to install (2) 10 inch subwoofers i dont know the wattage yet, and run (2) 6x9 off a amp. so basically i would be powering the facotry amp and two additional amps that i will be adding for the 10's and 6x9's

CamaroSkooter · 02-23-2010, 09:01 AM

Quote:

Originally Posted by strauchpete

...Caps only work on electronics that are connected with in max 18" of the caps power source...

This statement reads like you should have your capacitor within 18" of the car battery. I think what you mean is, caps only provide consistent voltage to any electronics that are connected within 18" of the capacitor. Meaning, you should have your amplifier(s) within 18" of the connection to the capcitor.

Other than that, though, nice write-up. There's always a lot of misconception when it comes to different electrical components available for aftermarket stereo systems.

Camar0wn3d · 02-23-2010, 04:36 PM

WHAT?!

I don't see why you have a sine wave when demonstrating a power capacitor's discharge properties. A capacitor in an amplifier power circuit helps to maintain a DC voltage as load fluctuations occur.

There would be no sinusoids in a car's power distribution system. If there are, then you have a rectifier problem, and a capacitor will NOT help...

What a power capacitor would see, even with an extremely high powered sound system, is a pretty constant voltage with a few dips here and there. See the graph below - the scale is not what a Car's electrical system would be (approx 14V when running), but it gives you an idea of what a DC Power capacitor does for you. (Note that the Voltage never goes negative...the Pink line (circuit with power / bypass capacitor) smooths out the valleys and makes for a cleaner supply voltage profile.

Also, I disagree with your statement about adding a capacitor won't stop your headlights from dimming. If the capacitor is sized right for the sound system application, it will definitely help keep the car's main DC supply more consistent (it may not COMPLETELY eliminate dimming, but it will definitely help a lot). It will still dim some during the loooong drawn out bass hits common to rap songs or techno, but the quick burst from a bass drum on rock music will have no dimming because the capacitor is able to charge back up from the car's alternator/battery between bass hits...

However, I do agree that adding a second battery will outperform a capacitor and is way more cost-effective for higher power systems.

Camar0wn3d · 02-23-2010, 04:44 PM

Quote:

Originally Posted by strauchpete

...So if you are having light dimming put a cap on your headlights and it will stop it....

You CAN do this, but

1.) it would be a much smaller capacitor and would not need to be one that costs near $150 to $500

2.)it is not really needed with a main supply bypass capacitor nor is it best practice because you are not addressing the underlying problem, which is the poor DC supply that can propagate to other electrical loads, (radio faceplate, ambient lighting, ECM, etc.)

Quote:

Originally Posted by strauchpete

So as you can see it discharges it charge very fast over a short span.

That is completely dependent on the capacitor rating and the resistance of the load it is attached to. A 3 Farad capacitor you are showing in your graph would actually have a decently long discharge time considering the load it would see during a bass hit.

Camar0wn3d · 02-23-2010, 06:48 PM

Quote:

Originally Posted by Sidewayz_510

so do you recommend installing a capacitor if i wish to install (2) 10 inch subwoofers i dont know the wattage yet, and run (2) 6x9 off a amp. so basically i would be powering the facotry amp and two additional amps that i will be adding for the 10's and 6x9's

Really need to know the wattage of the amps you're gonna use to give an answer.

Camar0wn3d · 02-24-2010, 12:55 PM

Quote:

Originally Posted by strauchpete

After typing up a long response to everyone of you, I just said Its pointless,and deleted it. Getting rude emails from people I just decided to remove this thread.

I have been doing car audio for over 10 years now professionally and in this industry everyone from the 16 yr old kid to the old man that used 8track is a self proclaimed expert, so I said why bother. I am MECP Basic, Advanced, Sales and ASE Eletrical but hey who cares.

All I was trying to do is give some of the people that really dont know alot about car audio some BASIC insight into caps, and I so they dont get screwed by someone or waste there money on something that would not fix the problems they have.

thx to everyone, probably wont be seeing me that much anymore on here.

It was not my intention to run you off of this thread, and you had some good points about the basics of how a capacitor works, but the details were sketchy and that graph you posted was entirely inaccurate. What you posted looked more like the output of a passive low pass filter which is on the audio signal side of things, NOT the power supply side.

I too have qualifications in this field as I have a BS in Electrical Engineering and currently work as an instrumentation/controls engineer. I deal with the principles I posted about on a daily basis both in theory and in practice.

Like you, I was merely trying to give some people that really don't know a lot about car audio basic insight into capacitors.

It was not my intention to be rude in my post (who sent you rude emails?) just trying to explain the theory a little more in detail.

JEFF2010SSMANUAL · 06-03-2010, 09:32 PM

Quick question about charging a cap. I usually just hook them up and they charge, I have read that its a good idea to first charge the cap before wiring to amp and battery, is this really needed. I usually get everything hooked up then install the large power+ fuse.

strauchpete · 06-03-2010, 10:05 PM

yes you want to charge the cap up first, it can damage the cap if you dont charge it first.

oachalon · 06-03-2010, 10:25 PM

Camar0wn3d,

you nailed it. For almost all car audio applications a cap is not needed. All the cap does is hide the actual problem.

I like seeing other engineering posts as i also have a BS in electrical engineering. My work right now is mostly with emi filtering and power supply design.

What kind of controls are you doing?

"That is completely dependent on the capacitor rating and the resistance of the load it is attached to. A 3 Farad capacitor you are showing in your graph would actually have a decently long discharge time considering the load it would see during a bass hit."

Gotta love tau=RC

JEFF2010SSMANUAL · 06-04-2010, 09:49 AM

I bought a good quality sub, amp, cap for my last car and didn't feel like installing it. I had never used a cap in systems I installed. When asked if I wanted a cap I said, Why Not. So I didn't get it to fix a problem, I purchased one because EVERY system I have seen in the past 10 years has at least 1 cap. The theory makes sense, a power storage unit for low frequencies that require alot of power to move a heavy large cone(sub). I DON'T have the money to buy a thousand dollar amp. I already have all the items from my last car. I wasn't going to add anything to my Camaro's audio system because I didn't want to ADD weight in the trunk (a heavy car already), but after seeing the wiring harness to allow a very simple way to get a signal to a sub amp in the trunk (with photo outs and turn-on lead) I decided to build a very small sealed box (MDF) for 2 12" Diamond subs I already have. I have a good quality amp thats stable at 2 ohms and is said to put out 1200 watts RMS clean. It never got real hot in my last car and never shut down. Since I already have a 1.5 farad cap I figured I would use it. I never thought of the cap as "a bandaid" (a fix), more like an extra power storage unit for low frequency woofer excursions which takes alot of energy. SHOULD I not use this cap??? I already designed the box using 3/4" MDF that I will highly brace and insulate with Dacron I purchased from "Parts Express". I also will over-insulate the sealed box which makes the woofers (subs) react as if they are in a bigger enclosure.

Should I then forget about using my Cap???

Any suggestions? I have installed MANY car audio systems since 1980, and designed and built MANY subs since 1990. I have a computor design software program (Bassbox 6.0) that I used when building bass-reflex enclosures. But since I don't want a big/heavy enclosure in my portly Camaro I am going with a sealed enclosure that will have extra Dacron insulation.

strauchpete · 06-04-2010, 01:23 PM

If you all ready got it use it, its not going to hurt your cars electrical system if you are not going big with it. But if you are going out to buy one save your money and get a better battery. The camaros have a 130amp alternator so they are plenty to charge a std street beat system.

JEFF2010SSMANUAL · 06-04-2010, 02:49 PM

Quote:

Originally Posted by strauchpete

If you all ready got it use it, its not going to hurt your cars electrical system if you are not going big with it. But if you are going out to buy one save your money and get a better battery. The camaros have a 130amp alternator so they are plenty to charge a std street beat system.

OK. I figured that. I have no extra money or credit, so a new battery is

out of the question. I have a Hifonics Brutus amp thats supposed to be

high quality. I would rather not use the cap due to people saying I have

to charge it. I installed 2 systems for other people using a cap and didn't

charge it, in fact I have seen many pro shops install them without charging

them. I have a diagram how to charge the cap, but don't like handling

them when charged, I am always afraid I will short the + to - terminal.

I thought my amp was 1200wrms at 2 ohms, but its 900wrms. Thats OK

my Diamond 12's handle 500rms and 900peak, so 2 of them at 2 ohms and

900wrms should be fine. Thanks

02-18-2010, 11:17 PM	#1
strauchpete Account Suspended Drives: 2010 Camaro 1LT Join Date: Dec 2009 Location: Sedalia, Missouri Posts: 338 View My Garage	Capacitor Information After typing up a long response to everyone of you, I just said Its pointless,and deleted it. Getting rude emails from people I just decided to remove this thread. I have been doing car audio for over 10 years now professionally and in this industry everyone from the 16 yr old kid to the old man that used 8track is a self proclaimed expert, so I said why bother. I am MECP Basic, Advanced, Sales and ASE Eletrical but hey who cares. All I was trying to do is give some of the people that really dont know alot about car audio some BASIC insight into caps, and I so they dont get screwed by someone or waste there money on something that would not fix the problems they have. thx to everyone, probably wont be seeing me that much anymore on here. Last edited by strauchpete; 02-23-2010 at 07:10 PM. Reason: People are rude and dont want help.

02-23-2010, 04:36 PM	#4
Camar0wn3d formerly "wh0rsep0wer" Drives: 2016 1SS Summit White Join Date: Oct 2008 Location: Myrtle Beach, SC Posts: 489	WHAT?! I don't see why you have a sine wave when demonstrating a power capacitor's discharge properties. A capacitor in an amplifier power circuit helps to maintain a DC voltage as load fluctuations occur. There would be no sinusoids in a car's power distribution system. If there are, then you have a rectifier problem, and a capacitor will NOT help... What a power capacitor would see, even with an extremely high powered sound system, is a pretty constant voltage with a few dips here and there. See the graph below - the scale is not what a Car's electrical system would be (approx 14V when running), but it gives you an idea of what a DC Power capacitor does for you. (Note that the Voltage never goes negative...the Pink line (circuit with power / bypass capacitor) smooths out the valleys and makes for a cleaner supply voltage profile. Also, I disagree with your statement about adding a capacitor won't stop your headlights from dimming. If the capacitor is sized right for the sound system application, it will definitely help keep the car's main DC supply more consistent (it may not COMPLETELY eliminate dimming, but it will definitely help a lot). It will still dim some during the loooong drawn out bass hits common to rap songs or techno, but the quick burst from a bass drum on rock music will have no dimming because the capacitor is able to charge back up from the car's alternator/battery between bass hits... However, I do agree that adding a second battery will outperform a capacitor and is way more cost-effective for higher power systems. Attached Images __________________ 2010 1SS/RS - CGM/Gray Interior - M6 (SOLD) Kooks 1 7/8" headers, Solo Mach-X, Vararam. 2012 2LS - Black A6 (SOLD) 2016 1SS Summit White A8 Last edited by Camar0wn3d; 02-23-2010 at 04:56 PM.

02-23-2010, 04:22 AM	#2
Sidewayz_510 Drives: 2010 BLK SS/RS & 2005 Range Rover Join Date: Apr 2009 Location: EAST BAY AREA, CA Posts: 46	so do you recommend installing a capacitor if i wish to install (2) 10 inch subwoofers i dont know the wattage yet, and run (2) 6x9 off a amp. so basically i would be powering the facotry amp and two additional amps that i will be adding for the 10's and 6x9's

06-03-2010, 09:32 PM	#8
JEFF2010SSMANUAL JEFF2010SSMANUAL Drives: IOM 2SS/RS LS3 Join Date: Aug 2008 Location: Northern IL Posts: 1,953	Quick question about charging a cap. I usually just hook them up and they charge, I have read that its a good idea to first charge the cap before wiring to amp and battery, is this really needed. I usually get everything hooked up then install the large power+ fuse.

06-03-2010, 10:05 PM	#9
strauchpete Account Suspended Drives: 2010 Camaro 1LT Join Date: Dec 2009 Location: Sedalia, Missouri Posts: 338 View My Garage	yes you want to charge the cap up first, it can damage the cap if you dont charge it first.

06-03-2010, 10:25 PM	#10
oachalon Drives: 2010 Camaro 1SS Join Date: Mar 2009 Location: Mentor, Ohio Posts: 999 View My Garage	Camar0wn3d, you nailed it. For almost all car audio applications a cap is not needed. All the cap does is hide the actual problem. I like seeing other engineering posts as i also have a BS in electrical engineering. My work right now is mostly with emi filtering and power supply design. What kind of controls are you doing? "That is completely dependent on the capacitor rating and the resistance of the load it is attached to. A 3 Farad capacitor you are showing in your graph would actually have a decently long discharge time considering the load it would see during a bass hit." Gotta love tau=RC

06-04-2010, 09:49 AM	#11
JEFF2010SSMANUAL JEFF2010SSMANUAL Drives: IOM 2SS/RS LS3 Join Date: Aug 2008 Location: Northern IL Posts: 1,953	I bought a good quality sub, amp, cap for my last car and didn't feel like installing it. I had never used a cap in systems I installed. When asked if I wanted a cap I said, Why Not. So I didn't get it to fix a problem, I purchased one because EVERY system I have seen in the past 10 years has at least 1 cap. The theory makes sense, a power storage unit for low frequencies that require alot of power to move a heavy large cone(sub). I DON'T have the money to buy a thousand dollar amp. I already have all the items from my last car. I wasn't going to add anything to my Camaro's audio system because I didn't want to ADD weight in the trunk (a heavy car already), but after seeing the wiring harness to allow a very simple way to get a signal to a sub amp in the trunk (with photo outs and turn-on lead) I decided to build a very small sealed box (MDF) for 2 12" Diamond subs I already have. I have a good quality amp thats stable at 2 ohms and is said to put out 1200 watts RMS clean. It never got real hot in my last car and never shut down. Since I already have a 1.5 farad cap I figured I would use it. I never thought of the cap as "a bandaid" (a fix), more like an extra power storage unit for low frequency woofer excursions which takes alot of energy. SHOULD I not use this cap??? I already designed the box using 3/4" MDF that I will highly brace and insulate with Dacron I purchased from "Parts Express". I also will over-insulate the sealed box which makes the woofers (subs) react as if they are in a bigger enclosure. Should I then forget about using my Cap??? Any suggestions? I have installed MANY car audio systems since 1980, and designed and built MANY subs since 1990. I have a computor design software program (Bassbox 6.0) that I used when building bass-reflex enclosures. But since I don't want a big/heavy enclosure in my portly Camaro I am going with a sealed enclosure that will have extra Dacron insulation.

06-04-2010, 01:23 PM	#12
strauchpete Account Suspended Drives: 2010 Camaro 1LT Join Date: Dec 2009 Location: Sedalia, Missouri Posts: 338 View My Garage	If you all ready got it use it, its not going to hurt your cars electrical system if you are not going big with it. But if you are going out to buy one save your money and get a better battery. The camaros have a 130amp alternator so they are plenty to charge a std street beat system.