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

RCA input noise problem
RCA input noise problem
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 15th June 2019, 08:34 AM   #11
wiseoldtech is offline wiseoldtech  United States
diyAudio Member
wiseoldtech's Avatar
Join Date: Dec 2018
Location: Philadelphia Pa USA
Any type of amplifer, preamp, will show hum when its inputs are disconnected because now the inputs have no source loading on them - they're "wide open".
To assume that an amp should be dead "silent" with wide open inputs is false thinking.
And bench testing of an amp with an AC powered supply, unless the supply is regulated and sufficiently filtered, will naturally be a source of background hum.
How do I know these things? - after formal electronics training and 45 years in the service business, I think I ought to know.
  Reply With Quote
Old 15th June 2019, 02:26 PM   #12
barber02 is offline barber02
diyAudio Member
Join Date: Jun 2018
Well. I am a little curious as to why some amps seem to be affected by this hum and some aren’t. It’s only every so often that I get an amp with this low volume hum with both RCAs plugged in on the work bench. It’s very low volume, but it’s there. Most amps don’t seem to mind the setup that I am currently using. It could be two amps from the same manufacturer identical in every way and one will exhibit this issue and one won’t. It is curious to me. That’s why I assumed it was a problem with the amp’s input.

Thanks to all for helping me understand this issue and sharing your knowledge. I really appreciate it. There is nothing more time consuming that chasing a problem that isn’t there.

  Reply With Quote


RCA input noise problemHide 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
Optical input/DAC and noise ClassZ Digital Line Level 0 9th July 2014 02:33 PM
Noise of LTP input? Help! Dave Zan Solid State 9 2nd March 2012 10:22 AM
Reduce input noise YUTK Solid State 18 27th December 2005 12:04 PM
Low noise input? MikeW Pass Labs 11 21st September 2005 11:57 PM
T Amp input noise pixpop Class D 9 27th May 2005 04:54 PM

New To Site? Need Help?

All times are GMT. The time now is 04:14 AM.

Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 15.00%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
Copyright ©1999-2019 diyAudio