Go Back   Home > Forums > >
Home Forums Rules Articles diyAudio Store Blogs Gallery Wiki Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

AC Line Filter
AC Line Filter
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
Thread Tools Search this Thread
Old 28th April 2012, 09:14 PM   #1
Ducs is offline Ducs  Canada
diyAudio Member
Join Date: Apr 2012
Default AC Line Filter

What do you guys think about installing a ac line filter before the power transformer. I am talking about something similar used in computer power supplies that doubles as a ac inlet. See pic below

Click the image to open in full size.
  Reply With Quote
Old 28th April 2012, 11:06 PM   #2
DigitalJunkie is offline DigitalJunkie  United States
diyAudio Member
Join Date: Apr 2003
Location: Portland,Oregon
Send a message via AIM to DigitalJunkie
Some of the "Golden Ear" crowd seem to think that they muddle up the sound.

Personally,I'm all for them. Keep the nasty crap from all the switching supplies,out of my amp. Never really noticed a big difference in sound,with or without,but it's good peace of mind.
  Reply With Quote
Old 28th April 2012, 11:13 PM   #3
boywonder is offline boywonder  United States
diyAudio Member
boywonder's Avatar
Join Date: Jan 2008
Location: So.Cal.
I've got 'em in all of my tube amp projects; they were leftovers from old work prototypes. The ones I have are Schurter 4A rated medical jobbies.

One thing that I have wondered about using them is......although they may be rated for say 4A, you could easily have pulses of greater than 4A depending on the conduction angle of the power supply rectifiers & caps, and I have no idea if they are still effective at high (pulsed) currents.

I did not use one in my last project, a Mini-A from the Pass Labs forum. (Class A SS).
  Reply With Quote
Old 28th April 2012, 11:43 PM   #4
Ducs is offline Ducs  Canada
diyAudio Member
Join Date: Apr 2012
Great...I am planning to use a Schurter power entry module with a switch, fuses and a filter - all in one package makes everything simpler and cleaner
  Reply With Quote
Old 30th April 2012, 03:27 AM   #5
gingertube is offline gingertube  Australia
diyAudio Member
Join Date: Oct 2004
Location: Adelaide South Oz
I don't build anything without a mains filter. Mains supplies are notoriously noisey. You want to keep that mains born noise out of your amp. This is particularly true when toroidal power trannies are used as they have huge bandwidth and noise couples to the secondary very well.
  Reply With Quote
Old 30th April 2012, 05:07 AM   #6
Junm is offline Junm  Philippines
diyAudio Member
Junm's Avatar
Join Date: Dec 2008
Location: Dau
Send a message via Yahoo to Junm
Default noise filters....

i'm also planning to use these things.....are they good?
Attached Images
File Type: jpg EMI.jpg (130.8 KB, 1217 views)
File Type: jpg Image0790.jpg (86.2 KB, 1182 views)
  Reply With Quote
Old 30th April 2012, 06:06 AM   #7
johnferrier is offline johnferrier  United States
diyAudio Member
johnferrier's Avatar
Join Date: Sep 2003
Location: WA
Some may find interest in the following audioXpress articles by Ed Simon (aka simon7000) . . .
An On-Peak Power Supply, Pt. 1
A Line-Cleaning Filter, Pt. 2
An Isolation Transformer, Pt. 3

I went with the following as well as added varistors and surge absorbers. (Oh, and a pair of Bybee's for the overboard factor.)

Click the image to open in full size.

Michael Gazzaniga - "The arts are not frosting but baking soda."

Last edited by johnferrier; 30th April 2012 at 06:09 AM.
  Reply With Quote
Old 30th April 2012, 10:05 AM   #8
kaputt is offline kaputt  Germany
Join Date: Sep 2011
Location: Berlin
I used the exact thing pictured in my poweramp (300B-XLS SET). I than changed to an unfiltered socket and sound became much clearer and alive.
  Reply With Quote
Old 30th April 2012, 10:50 AM   #9
AndrewT is offline AndrewT  Scotland
Join Date: Jul 2004
Location: Scottish Borders
I have a variety from 1A to 6A fitted to all my audio gear.

I have a few high current common mode inductors to allow discrete building if I need more current ability.
regards Andrew T.
  Reply With Quote
Old 30th April 2012, 10:55 AM   #10
mississippi is offline mississippi  Netherlands
diyAudio Member
mississippi's Avatar
Join Date: Apr 2006
Location: holland
My opinion:
If you hear a difference between filtered and unfiltered comes because you know when the filter was there or not.
After rectifying there is a DC voltage on your caps, and there is no difference there with or without filter.
Since you amplifiers works on DC voltages, I think the sound difference is between your ears !
  Reply With Quote


AC Line FilterHide 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

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
jon risch AC Power Line Filter - q's sunrise Power Supplies 26 30th April 2017 09:42 PM
AC Line Filter-Parts Recommendations croy00 Parts 11 13th September 2011 08:01 AM
possible to filter dips in AC line? ryuji Tubes / Valves 28 7th April 2011 04:23 AM
Pics of My AC Line filter project JOE DIRTŪ Everything Else 30 20th June 2003 01:33 PM

New To Site? Need Help?

All times are GMT. The time now is 10:32 PM.

Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 15.00%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Copyright ©1999-2018 diyAudio