Capacitor question - diyAudio
Go Back   Home > Forums > Design & Build > Parts

Parts Where to get, and how to make the best bits. PCB's, caps, transformers, etc.

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 15th January 2002, 12:39 AM   #1
diyAudio Member
 
Join Date: Jan 2002
Location: Tyrone Ga. U.S.A.
Default Capacitor question

If I were to build a power supply using a center taped transformer and a full wave bridge to supply + and - 30vdc
at 5a what would be the minimum ripple current rating needed
for the filter caps?


Thanks

bob12345678 aka Woody I had some trouble logging on!
  Reply With Quote
Old 15th January 2002, 03:23 AM   #2
diyAudio Member
 
Join Date: May 2001
Location: New Zealand
Here's some formulae...

The ripple current through a capacitor for a full wave rectifier system is:

Ir = Er * 2 * pi * f * C

Where Er is the ripple voltage, f is the frequency in hertz and C is the capacitance in farads.

Calculation of Er is more difficult. You need to know all the source resistances. Better to measure it. If you want the details, and you're able, find a copy of the Radiotron Designer's Handbook and read pages 1177 to 1182.

Good luck, Keith
  Reply With Quote
Old 1st February 2013, 06:26 AM   #3
kuma33 is offline kuma33  Hungary
diyAudio Member
 
kuma33's Avatar
 
Join Date: Jan 2013
Location: Szeged
Hi guys,
can anyone tell me what are the electrolytic's specifications what influencing the audio signal? Or just the dielectrics material, the foil material, etc.? I have some Hitano EHR series el.caps, but the documentations aren't containing informations about the usability in audio applications..
  Reply With Quote
Old 1st February 2013, 11:37 AM   #4
DF96 is offline DF96  England
diyAudio Member
 
Join Date: May 2007
Such a simple innocent question!

If there was a straightforward agreed answer then many threads on here could disappear and audio design would be more of an engineering discipline with less space for snake oil merchants and postmodern tree huggers.
  Reply With Quote
Old 1st February 2013, 11:53 AM   #5
DUG is offline DUG  Canada
diyAudio Member
 
Join Date: Jan 2003
Location: mississauga ontario canada
Quote:
Originally Posted by kuma33 View Post
Hi guys,
can anyone tell me what are the electrolytic's specifications what influencing the audio signal? Or just the dielectrics material, the foil material, etc.? I have some Hitano EHR series el.caps, but the documentations aren't containing informations about the usability in audio applications..
The usual answer to general questions is:

It depends.

It depends on what you are using the cap for.

Electrolytics for power supply filtering...If lower ability then increased ripple or droop under load could cause increased 120Hz in output of amplifier or clipping at lower power levels. Transient or sudden power requirements may not be provided for with "lower grade" caps.(all other factors the same)

Electrolytics for signal coupling...here is where opinions vary.

IMHO, if the Electrolytics cap can maintain a low enough impedance throughout the frequency range of interest then there is no issue with its use for signal coupling.

Some data sheets will have information that will help you decide but it may not be blatantly labeled as "for use in xxxxx application"

Hope that helps.
__________________
Doug We are all learning...we can all help
"You can't stop the signal, Mal. Everything goes somewhere..."
  Reply With Quote
Old 1st February 2013, 05:18 PM   #6
kuma33 is offline kuma33  Hungary
diyAudio Member
 
kuma33's Avatar
 
Join Date: Jan 2013
Location: Szeged
Okay, i know the boof stuff, like "woodknob-resonance" or "amp chassis sound conduction", but the caps are different, because they are really in the signal path, like coupling or output elements..
But there are hundreds of cap types from low esr to long life, etc., and audio types too, like the silmics, with many, many parameters...
  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
Capacitor Question... SigloOne Tubes / Valves 26 30th May 2013 10:42 AM
PSU Capacitor question Cloth Ears Chip Amps 11 17th January 2010 11:56 AM
Capacitor question... Again and again... Dxvideo Chip Amps 14 9th January 2008 08:27 AM
capacitor question crippledchicken Solid State 3 31st October 2007 09:12 PM
Capacitor Question audiodumb Car Audio 15 22nd June 2005 03:49 PM


New To Site? Need Help?

All times are GMT. The time now is 07:05 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