X1/X2 Capacitors AC in, adding noise to the system!? - Page 2 - diyAudio
Go Back   Home > Forums > Design & Build > Construction Tips

Construction Tips Construction techniques and tips

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 17th December 2010, 09:55 PM   #11
godfrey is offline godfrey  South Africa
diyAudio Member
 
Join Date: Nov 2009
Location: Cape Town
Quote:
Originally Posted by Destroyer OS. View Post
I am not sure what 2u2 means...
2.2 microfarads
  Reply With Quote
Old 17th December 2010, 10:03 PM   #12
DF96 is offline DF96  England
diyAudio Member
 
Join Date: May 2007
Quote:
Disadvantages of LC filters:
~ Must be designed for specified source and load reistances.
~
~ Inductors that are close to ideal inductors are difficult to design, so the final design must be "tweaked" to allow for finite Q, distributed capacitance.
This is only true for LC filters which must provide a specific filter passband/stopband/phase response e.g as used in RF or video systems. This is the type of filter which filter books generally talk about, not a mains filter.

If you just want to get rid of interference (the function of a mains filter) then almost any reasonable values will help. Just avoid resonance at critical frequencies. If necessary (it rarely is) cascade two filters covering different bands (e.g. HF, VHF).
  Reply With Quote
Old 17th December 2010, 10:44 PM   #13
diyAudio Member
 
Join Date: Nov 2005
Yes we do a similar thing.

I will tell you that the Magnapan article recommended a 200mfd capacitor across the N to E. I use that and a few other sizes bypassing it. The voltage is not particular on this nor do I bother with X/Y capacitors. I use cheap Solen's and Vishay filter cap.

Each AC receptacle socket I have I broke the tabs off so they are two independent sockets that both have CMCs (I use to not have that many CMCs and did one per socket but heck why not do more? it provides somewhat better filtration and more current per socket). I prefer to use the highes mh I can but depending on a few things like how much current I want a particular socket to provide it controls the size and mh. I have heard of larger inductors I could use like in Grey's power conditioners that are 10mh and handle large current. They are also enormous and potentially not as big of a benefit as they space and cost merit. Sometimes I prefer no inductor on some amplifiers so I leave some sockets without.

What do you mean by L+N to earth?
  Reply With Quote
Old 17th December 2010, 10:49 PM   #14
diyAudio Member
 
nigelwright7557's Avatar
 
Join Date: Apr 2008
Location: Carlisle, England
Quote:
Originally Posted by Destroyer OS. View Post
What do you mean by L+N to earth?
A Y type 2u2 capacitor from live to earth and neutral to earth.

"I use cheap Solen's and Vishay filter cap."

This is illegal in the UK, they must be X and Y rated capacitors which are self healing.
__________________
PCBCAD50 software. http://www.murtonpikesystems.co.uk
  Reply With Quote
Old 17th December 2010, 11:32 PM   #15
diyAudio Member
 
Join Date: Nov 2005
Legality? Sorry that occurs for you. The neutral to earth simply does not have the need for high voltage. I would not use them in other places, only X/Y.

They are not self healing capacitors, they are just guaranteed to fail in a specific way.

I have hear some criticism of Y capacitors and what they do to sound. I have yet to bother with them.
  Reply With Quote
Old 18th December 2010, 12:28 AM   #16
diyAudio Member
 
Join Date: Nov 2005
The same is true for neutral to earth ground filter capacitors which is even more important actually, that they be arranged thusly.

The point being that if you do not wire like this you run the potential of introducing noise back into your system. The only way to protect it is to have a capacitor on every single piece of equipment, of the same value. It works for audience adept but their filtration is weak compared to what you can make for yourself. I grant that people here share that aspect with essentially everything though.

You will get more attenuation from stacking the capacitors you already have at the input taps anyways. There is a limit though where you can start attenuating the 60hz but that limit is above 100mfd where it starts to matter. For the neutral to earth it means nothing, like I said that old magnapan website article recommended 200mfd with a say 10mdf and 1mdf bypassing it. First hand experience is that it does wonders for cleaning up digital. In fact it is so powerful you can make a filter with just those in it and plug it in, in another room and still get the benefit if you are on the same breaker. (Magnapan suggested that due to hum but mine have never made a noise)

Click the image to open in full size.
  Reply With Quote
Old 18th December 2010, 09:45 AM   #17
AndrewT is offline AndrewT  Scotland
diyAudio Member
 
Join Date: Jul 2004
Location: Scottish Borders
Quote:
Originally Posted by Destroyer OS. View Post
Legality? Sorry that occurs for you. The neutral to earth simply does not have the need for high voltage. I would not use them in other places, only X/Y.

They are not self healing capacitors, they are just guaranteed to fail in a specific way.
you should not be allowed to post these untruths.

Legality and Safety rise above all else. This applies in this Forum as well.
__________________
regards Andrew T.
  Reply With Quote
Old 18th December 2010, 11:06 AM   #18
Did it Himself
diyAudio Member
 
richie00boy's Avatar
 
Join Date: Nov 2003
Location: Gloucestershire, England, UK
Quote:
Originally Posted by nigelwright7557 View Post
A Y type 2u2 capacitor from live to earth and neutral to earth.

"I use cheap Solen's and Vishay filter cap."

This is illegal in the UK, they must be X and Y rated capacitors which are self healing.
2u2 on earth is against regulations. 4n7 is the max total capacitance allowed.

Y rated are allowed across earth and live/neutral and also across live and neutral. X rated are only allowed across live and neutral. X and Y fail in different ways.
__________________
www.readresearch.co.uk my website for UK diy audio people - designs, PCBs, kits and more.
  Reply With Quote
Old 18th December 2010, 11:11 AM   #19
DF96 is offline DF96  England
diyAudio Member
 
Join Date: May 2007
Putting huge capacitors across the mains supply should be unnecessary, unless your supply is astonishingly dirty. Even then an LC filter will be better. They should always be mains-rated capacitors, and not create too much 'reactive power'.

If there are huge noise spikes etc. then wiring your mains bus should follow similar rules as those used for safe low noise grounding i.e. watch where the currents flow. I think I am beginning to see what you mean by capacitors "creating noise". They don't, but wiring big capacitors in the wrong place can ensure that noise already present is not suppressed but injected into equipment. You want to suppress noise at the point it enters the bus, not create noise currents through the bus itself. Hence the capacitor should be where the noise enters. With a fairly clean supply this will be less critical.
  Reply With Quote
Old 18th December 2010, 11:03 PM   #20
diyAudio Member
 
Join Date: Nov 2005
Quote:
Originally Posted by AndrewT View Post
you should not be allowed to post these untruths.

Legality and Safety rise above all else. This applies in this Forum as well.
What untruth do you speak about? The capacitors ARE guaranteed to fail in a specific way and that is why they are used in circuit environments that have more potential danger.

Using not low but lower voltage capacitors on neutral to earth makes perfect sense because you are only removing inducted charge. Without line connected in anyway there is not a complete circuit so no matter which direction the AC flows it will never have current from the fusebox, transformer outside, power substation, or power producer. It is not possible and that is why line is called line and neutral is not called line 2. Plus I trust Magnapan's techs more than you.

DF96 you can say what you will but until you have heard you just do not know. It is easy to argue about what we think is going on based on all the theories we are aware of but... Hands down I tell you that my way of power conditioning improves what people thought were dedicated circuits to their system in a neighborhood that seems fairly clean with adequate power. Even non-audiophiles can tell right away. You just have to hear to understand. My former roommate requested I get my unit back when I let a friend borrow it to try in his system. My roommate just listened to music and was not in the slightest way an audiophile but he KNEW when it was gone.

I use CMC's. They have extremely low resistance so as far as inductors go they may not be creating the particular crossover you have in mind but they do very well at removing noise. Coilcraft Combination Line Filter Choke Those are some that I like to use but for larger power requirements sometimes I get some off of digikey but for anything that uses large current flow I typically prefer nothing. I am playing with the idea of very large ones like in Grey units but I am not sure there is a way to use them due to size.

However the LC does sound interesting but it sounds like something that would have to be used inside of a component due to the fact of what I posted earlier about in order for it to work, from what I know, it is specific to the load. To me that would mean that changing loads (plugging in new or removing equipment) would mean changing the LC to correct. Let me know if I am wrong and I would love an example of an LC circuit you might use.

I appreciate the good explanation of noise. It still brings up the point that X capacitors over AC in on equipment pieces does have the potential for introducing noise in non-perfect environments, which is pretty much any environment.
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
X2, AC Line Capacitors Speedskater Power Supplies 7 2nd December 2010 03:29 PM
Mesure DC in AC outlets Cant find what is making noise in my AC 30CCX Help!!! !!! Ulisez Power Supplies 13 23rd November 2010 06:42 AM
FS - NHT X1/X2 Crossover PCB Boards Guiness Swap Meet 1 5th October 2010 06:27 PM
is it okay to use an X1/X2 film cap in this circuit... jarthel Parts 12 7th July 2007 12:39 PM


New To Site? Need Help?

All times are GMT. The time now is 11:29 AM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright 1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2