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Old 12th November 2006, 00:32   #1
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Default Caps inside Mono amps?

Hi all,

This thread might sound stupid to many..but cant help as this question is popping into my head.

I was wondering that cant caps be embedded into mono amps. Now we all know that we use caps with mono amp because of less battery power and bla bla bla....

Now, after buying a mono amp we do prefer buying a cap. Is there brand that make mono amps which have caps inbuilt?

Now many would say that size of a cap is big and cant be fit into a amp...but come one, technology has advanced so much.... When movie camera which, in its early days used to look like a rocket launcher kept on shoulders, is now put in phones and pens, why cant caps be put into amps?


Amit
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Old 12th November 2006, 09:11   #2
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Oh well, what a Sunday. Firstly to go to sleep on a saturday night with no sex, now this question. lol

Amit,

All amplifiers (home and car) have caps in them. They typically vary between 4700mfd to 6300 mfd (there is no hard and fast rule here) mostly there will be an entire bank of these, resulting in close to 20000mfd. (2X10raised to 3 mfd). Actually the industry standard for measuring capacitance is is MICROfarad.
These capacitors are placed in the secondary section of the power supply. Let me explain - though it seems that a car amplifier runs on 12V, it actually runs on voltages much higher than those. A car amplifier typically uses a chopper smps, to upscale 12V to voltages many times higher.
A capacitor has 2 basic properties. How many MicroFarad and how many maximum volts it can handle.

Caps generally used inside these amplifiers have a higher voltage limit, as car amplifiers run from 44VDC to 150VDC internally. again there is no hard and fast rule, this will depend on the manufacturers circuit design. The role of the internal cap is to smoothen out the spiky waveform of the voltage generated by the internal chopper transformer and power supply.

The external capacitor however, is attached in the PRIMARY circuit. BEFORE the 12V is upscaled, chopped or converted. It's role is to provide a steady 12V and a lower transient response time with minimum dipping or peaking.
Though it's capacitance is high 1FARAD is 1X10raised to 6mfd, it's maximum voltage rarely exceeds 15V, because it doesnt need to.

However, a 1F, 100V capacitor (also known as a condensor) would probably be bigger than a NOS cylinder.

Considering your argument about small technology, let me consider your very example. The best cameras are still big. That's why rudra did not buy a Nokia N90 instead of a Canon EOS1D. Consider that the canon EOS1 size is more or less the same for about 20 years now.
Remember, they dont make movies with a Sony ericsson, they still have huge dollies with rocket launchers on them.
Small technology often is pseudo technology.

Now that we have understood the difference between the inner caps and external caps, and why a good technology can never be too small (too soon), let us consider your question - why do companies not incorporate a (say) 0.5F capacitor inside the amplifier.
Thats because not everyone who buys a mono amplifier needs to or thinks he needs to put a capacitor. Though technically it should help a lot, often the results are not very audible to all. A capacitor is not an absolute necessity. Often I would put it last on a list, or not at all. It is more important to get good equipment, followed by good cables, damping and then if you feel the need, you add a cap. Also you ONLY add a cap when you play loud and hard, basically when your current draw is huge and fast. otherwise, the car battery is probably the best capacitor you've got.
When you have something that is expensive and not required by all, why would you change the market value of an amplifier, by adding a capacitor to it?
Capacitors are a matter of choice and that's why companies will leave it that way.

Hope this shed some hair,

Dhoom machale dhoom, but responsibly.

Last edited by Sam Kapasi : 12th November 2006 at 09:17.
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Old 12th November 2006, 12:48   #3
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Quote:
Originally Posted by Sam Kapasi
Hope this shed some hair,
WOW! it sure shed a whole lot for me.

And I really can't believe you could think this straight at 9 on a Sunday morning. Quiet saturday evening, huh?

I think we should rename this thread as "Everything you wanted to know about a Cap but were afraid to ask".

And this is definitely a sticky-worthy thread. Or this should at least be merged with the Glossary thread. Navin? How 'bout it?
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Old 12th November 2006, 12:52   #4
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Ohohoo what a reply !! Very well written sir. That definately cleared a lot of things in my head.

Just 1 more thing , you said one needs an external capacitor only if you play loud and hard so I mean if a company is building a particular amp with a specifeid o/p rating(the ones with 500+ rms), which would be expected to play "loud and hard" wouldn`t it be best to provide the max required capacitor builtin them, so that the amp can work in its full capacity without the need of any external help. Im sure the cost would definately rise up and so will the size in that case but it will be worth the cost....wat say ??

sorry to do this to you on a sunday brother...but the more you know is the less you know

Quote:
Oh well, what a Sunday. Firstly to go to sleep on a saturday night with no sex, now this question. lol
and yea hope you get lucky today

amit
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Old 12th November 2006, 14:14   #5
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Companies make an amplifier assuming good clean and a responsive Power supply. Often ratings aare given at 14.4V instead of 12V (this is to make the power ratings appear higher)
This is not a con job, as a running car will generate 13.5 to 14.5V instead of 12.

The capacitor is part of the 12V electrical circuit. Much like the alternator and the battery and the cables.

The job of the amplifier begins from the amplifier itself. With your argument, the amplifier carton should contain 0guage power cables, a distribution block, gold plated battery terminals and perhaps a high current, deep-cycle battery.

No amit, the design of an amplifier does not require it to have a capacitor across it's power terminals. It is a widely accepted school of thought that the capacitance provides a cleaner faster supply to the amplifier, resulting in a slightly better bass response.
You can just about manage to hear the difference a capacitor makes, ONLY when you hit a low, loud bass note. Thhat's when the amplifier needs current...and quickly.

There are many that believe the entire capacitor thinking is a marketing gimmick. I for one do not think it is a gimmick, but i do not consider a cap as a priority.
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Old 12th November 2006, 14:52   #6
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Quote:
Originally Posted by Sam Kapasi
With your argument, the amplifier carton should contain 0guage power cables, a distribution block, gold plated battery terminals and perhaps a high current, deep-cycle battery.
Hehe ..how i wish..

neways thanks Sam i guess your explanation clears it all now....even some part of my scalp !! Appreciate your time and effort to solve my query....

cheerz
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Old 12th November 2006, 17:37   #7
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Quote:
Originally Posted by amit_sound
Ohohoo what a reply !! Very well written sir. That definately cleared a lot of things in my head.

Just 1 more thing , you said one needs an external capacitor only if you play loud and hard so I mean if a company is building a particular amp with a specifeid o/p rating(the ones with 500+ rms), which would be expected to play "loud and hard" wouldn`t it be best to provide the max required capacitor builtin them, so that the amp can work in its full capacity without the need of any external help. Im sure the cost would definately rise up and so will the size in that case but it will be worth the cost....wat say ??

sorry to do this to you on a sunday brother...but the more you know is the less you know



and yea hope you get lucky today

amit
Good amps have solid capacitor banks. They look the aerial view of a petroleum depot.

One of the most distinct advantages of adding an external power cap is the rapid discharge rate. So, when the power delivery is exceeded momentarily, the power cap is able to discharge and provide power instantaneously. This, your battery can't do. To store so much extra power for transients, the amp would have to be unnecessarily over-engineered.

Sam has listed the others.

Quote:
Originally Posted by Sam Kapasi
Oh well, what a Sunday. Firstly to go to sleep on a saturday night with no sex, now this question. lol
You can say that again. And I thought all the alcohol, cannabinoid vapors and John Digweed (I Dig Weed!) behind the decks last night would serve as an aphrodisiac (for the ladies, I'm perfectly virile and potent)! Met Sahil and elf there, you passed?

But atleast I didn't ruin my Sunday by getting up as early as you did.

Last edited by Bass&Trouble : 12th November 2006 at 17:39.
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Old 12th November 2006, 17:47   #8
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Quote:
Originally Posted by Sam Kapasi
There are many that believe the entire capacitor thinking is a marketing gimmick. I for one do not think it is a gimmick, but i do not consider a cap as a priority.
well said sam.
I feel that capacitor along with equalizer r two most overused items in ICE but on the other hand wiring and damping material r more neglected though later r more important.
The reason may be that cap and EQ r more of glamourous item and appealing to eyes whereas damping material and wiring wont be visible to any.
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Old 13th November 2006, 12:17   #9
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Quote:
Originally Posted by Sam Kapasi
...They typically vary between 4700mfd to 6300 mfd (there is no hard and fast rule here) mostly there will be an entire bank of these, resulting in close to 20000mfd. (2X10raised to 3 mfd). Actually the industry standard for measuring capacitance is is MICROfarad.
These capacitors are placed in the secondary section of the power supply.....
Caps generally used inside these amplifiers have a higher voltage limit, as car amplifiers run from 44VDC to 150VDC internally. again there is no hard and fast rule, this will depend on the manufacturers circuit design. ....
Sam, you are begining to sound like the old me. :-)


Quote:
Originally Posted by amit_sound
Ohohoo what a reply !! Very well written sir. That definately cleared a lot of things in my head.
Shouldn't that read "on my head". From what I am told all this tech stuff has contributed to "clearing" the top of many a head. :-)

Quote:
Originally Posted by Sam Kapasi
No amit, the design of an amplifier does not require it to have a capacitor across it's power terminals..
Many amps do have significant ammount of internal capacitance (as much as 60,000ufd). I use ufd for micro farad so as not to confuse with mfd which is also used for milli farads (1 mfd = 1000ufd).

Now 20-60,000ufd across a resistance of about 4ohms will give you a few millisecs of "transient management" as long as the transistors can handle the extra current. Adding a 1F/15V cap across the primary mean that unless the battery voltage has dropped or the current draw required is such that the intercal caps have been exhausted this 1F/15V cap wont be needed.
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Old 13th November 2006, 14:00   #10
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A brochure from lightning audio, one of the leading distributors of capacitors and related products, says it well.-------

The purpose of adding lightning caps to a car audio system is to improve your systems transient response. Lightning caps deliver quick energy to the DC to DC converter section of your amplifiers which it needs to accurately reproduce musical transients. Lightning caps stabilize the voltage from your car's electrical system providing your amplifiers with a very stable, high current powersupply.

How do you know you need a stiffening capacitor????????

If your system has a bass notes that hit hard and tight at first, but then seem muddy and distorted as the song plays on - you may need a reinforcing capacitor. Another symptom is headlight dimming on bass notes.
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Old 14th November 2006, 00:24   #11
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Quote:
Originally Posted by Sam Kapasi
Hope this shed some hair,
Yes shed a lots of hair.
But that was a good information.
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Old 14th November 2006, 10:13   #12
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Quote:
Originally Posted by kURETI
A brochure from lightning audio, .....
How do you know you need a stiffening capacitor????????

If your system has a bass notes that hit hard and tight at first, but then seem muddy and distorted as the song plays on - you may need a reinforcing capacitor. Another symptom is headlight dimming on bass notes.
You dont expect a cap maker not to recommend a cap do you? :-)

Before you get a cap upgrade the Big 3 wires. then if you still feel you need 200ms so of battery support get a cap. remember the amp must be capable of delivering the extra current as well.
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Old 14th November 2006, 16:18   #13
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the capacitor charges up to the alternator's voltage. when your system demands peak-current during musical transient, the capacitor discharges its energy quickly at the same volatge as your alternator. This provides your amplifiers with the current they need to accurately reproduce musical transient. These capacitors feature ultra low ESR (equivalent series resistance), about 1milliohm, so they deliver enery very, very quickly.
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Old 23rd November 2006, 16:53   #14
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I would suggest that one install a good battery in place of a Capicator.
Optima for instance.

It is better than putting the 'best' cap in the world in any car. I just removed the caps from my car & the sound has improved [I know you guys will go up in arms with this] but just try and put the battery in your set up & listen for the differance.
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Old 24th November 2006, 02:44   #15
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Quote:
Originally Posted by BHAGWAN View Post
I would suggest that one install a good battery in place of a Capicator.
Optima for instance.

It is better than putting the 'best' cap in the world in any car. I just removed the caps from my car & the sound has improved [I know you guys will go up in arms with this] but just try and put the battery in your set up & listen for the differance.
For the most part... you're right! In some systems, a cap can actually improve system output and sound. But for most systems, its best left out.

A good battery is important, but good doesnt necessarily mean an Optima. Optimas, though nice when they work, have had a high failure rate of late and one may be better off buying an Amaron Pro / Bosch Silver for 1/3rd the money.
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