Capacitor and System Noise

[Jeffdachef 5,000+ posts]

So I came across this video talking about capacitors reducing the noise floor with RTA tests done too. Vid is not talking about using caps for voltage, but more for noise reduction.

https://www.youtube.com/watch?v=T9mlvbF0flM&feature=youtu.be


what are your thoughts? If its true then you can benefit having one in line with your 4 channel amp if you have a noisy amp or alternator whine issues due to noise(especially if you have an overly noisy car).



@Chris Davies If all else fails, this or a ground loop isolator might help your noise issue.

Click to read more...

 

[gckless 5,000+ posts]

I think you should test it and report back.

 

[adulbrich 5,000+ posts]

So where exactly are you putting the capacitor? In parallel with your sub amp or mids/highs amp?

 

[LosIsATool 5,000+ posts]

I do believe that was their intended purpose

 

[trumpet 5,000+ posts]

This is not a detail I caught, but the settings on the RTA are dialed in a way to make the signal scale "bigger" for the camera. Yes, good quality capacitors make excellent noise filters, but the magnitude of the AC ripple shown in the video is low enough to not be a problem without the capacitor. Also, there is no load on the outputs of the amplifier.

 

[adulbrich 5,000+ posts]

Would something like this work?

16V 83F Ultracapacitor Engine Battery Starter Booster Car Ultra Super Capacitor | eBay

 

[fasfocus00 5,000+ posts]

the problem is that too many people that for or against capacitors don't even know what a capacitor is suppose to do than start making claims of what they think they will do. capacitors do their job very well if you know what a capacitor really is.

 

[wew lad 5,000+ posts]

I thought that a good battery acts like a large capacitor and mitigates AC current, kinda makes this seem useless.

You'd be better off eliminating the source of the AC ripple instead of adding more crap IMO but i guess it depends on the limitations of your install

 

[WhiteYota]

There are many different types of cap's with the most common usage as a power cap - that acts like a buffer on the power side.
A capacitor does have an advantage over any battery - speed. A cap can provide the the full power it is holding in microseconds where a battery has limitations to how fast it can respond with the same power demands.
That does not mean that a capacitor is a fix everything, but they have there place when designed into the audio build properly.


However for those who do not know about other functions - take apart a passive crossover. Most common components are resistors, capacitors and inductors.
Here is a link to more information on them - Wikipedia - Audio Crossover
I have built a few crossovers for home audio when I built my tower speakers.

For noise - yes it is always better to eliminate the source if it can be found - but sometimes it can cost more time and/or money then it is either worth or that is available. So why not add a filter if it does not affect the audio except the noise your trying to get rid of.
@Jeffdachef - Thanks for the suggestion, I was actually thinking about something like it, put it inline on the input to the sub amp.

 

[Jeffdachef 5,000+ posts]

I think you should test it and report back.

Dont have an RTA nor any noticeable noise.

 

[wew lad 5,000+ posts]

If it can be reproduced and shown to be a solution that offers significant noise reduction then I would definitely try it. I'll wait until there's some more evidence though, kinda surprised this hasn't been tested more thoroughly capacitors aren't really "new' technology.

 

[massivespl]

If u want to run caps u get maxwell or xs power ones. XS Power SuperCELL - XS Power

 

[gimling]

To give the easiest to understand answer here it is. A capacitor becomes a resistor or resistance when AC is run through it, basicly as the frequency increases through the capacitor the more AC Capacitance(RESISTANCE) you will get. So higher frequencies will be cut at a higher rate than the lower ones. but overall the current and voltage of the ac will be cut down. Thats why you still see some dancing on his RTA the "db" has been cut, there are formulas to find out just how much but i doubt anyone wants to know them.

 

[gckless 5,000+ posts]

Thanks for the suggestion, I was actually thinking about something like it, put it inline on the input to the sub amp.

Why would you put it there? You're least likely to notice noise there.

If it can be reproduced and shown to be a solution that offers significant noise reduction then I would definitely try it. I'll wait until there's some more evidence though, kinda surprised this hasn't been tested more thoroughly capacitors aren't really "new' technology.

This has been tested before. Where do you think OP got this idea?

 

[WhiteYota]

Why would you put it there? You're least likely to notice noise there.


This has been tested before. Where do you think OP got this idea?

It would not be to keep the noise out of my sub amp but to keep my sub amp from putting noise back into the rest of the system. I think that my sub amp is back feeding noise into rest of the system through the rca's. It is the only component that I have not and can not try a different one.

Sent from my iPhone using Tapatalk