What could be wrong if running a ground - diyAudio
Go Back   Home > Forums > Amplifiers > Solid State
Home Forums Rules Articles diyAudio Store Gallery Wiki Blogs Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

Solid State Talk all about solid state amplification.

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 16th September 2002, 07:52 PM   #1
diyAudio Member
Join Date: Aug 2002
Location: CA
Question What could be wrong if running a ground

wire from ANY of my sources to my brand new-just finished -(finally) Leach amp causes a very nasty (60Hz?) hum to vanish completly? ( Amp is dead silent before introducing an input from a source) I first tried lifting the third conductor from the wall plug as per the Leach site, no change. Then I tried using just one of the source's RCA inputs, hum volume decreased at least by half- but still there. I tried inverting the wall plug for the source AC power- no change. Then I added a temporary jumper wire from the source chassis to amp chassis--complete and utter silence even at full gain. Perfect fix. Plays fine- all day long- no problem. OK, I can live with that, but what the heck could be going on that adding this jumper wire is the apparent cure?
I know, another ground loop nightmare!
Thanks for your thoughts and help.
  Reply With Quote
Old 16th September 2002, 10:04 PM   #2
diyAudio Member
Join Date: May 2002
Location: Cincinnati, OH now Columbus,OH USA
Send a message via AIM to BeanZ
It sounds like your amplifier does not have a solid chassis ground connected to the "star" Grounding point. Make sure that all your grounds including: two speaker returns, power supply common, signal return, power return, and earth are all connected to a single point on the conductive chassis. Also check to make sure that the signal lines are not touching the chassis. Remember that there are two grounds per board/channel in this amplifier. Also, are you using a true earthed outlet?

  Reply With Quote
Old 16th September 2002, 10:05 PM   #3
skaara is offline skaara  Slovenia
diyAudio Member
Join Date: Jun 2002
Location: Europe, Slovenia
ou must ground signal gnd to wall gnd somewhere. You might didnt do it in your amp..
  Reply With Quote
Old 17th September 2002, 08:18 AM   #4
djk is offline djk
diyAudio Member
djk's Avatar
Join Date: Feb 2001
Location: USA

Check R51, it may not be there, it may be the wrong value, it may be open. You probably have a ground loop.
  Reply With Quote


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
Should I directly connect my signal ground to chassis ground? Bricolo Solid State 4 18th March 2014 09:42 PM
What advantages running ported midbass if you are running a sub? mitchyz250f Multi-Way 3 20th May 2008 02:34 PM
Wrong Voltage / current on BoZ... or Wrong Measuring ? gionag Pass Labs 8 14th May 2008 11:24 AM
Parallel LM3886, input ground, power ground, safety resistor and oscillations. markiemrboo Chip Amps 5 9th August 2007 03:50 PM
does connecting mains ground with circuit ground create a ground loop? jarthel Everything Else 0 25th June 2003 12:55 PM

New To Site? Need Help?

All times are GMT. The time now is 04:29 AM.

vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Copyright 1999-2017 diyAudio

Content Relevant URLs by vBSEO 3.3.2