Electrical noise - diyAudio
Go Back   Home > Forums > Source & Line > Analogue Source
Home Forums Rules Articles diyAudio Store Gallery Wiki Blogs Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

Analogue Source Turntables, Tonearms, Cartridges, Phono Stages, Tuners, Tape Recorders, 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 19th May 2017, 04:17 PM   #1
onis_uk is offline onis_uk  United Kingdom
diyAudio Member
 
Join Date: Jul 2004
Location: uk
Default Electrical noise

I have my amp plugged into my Samsung TV via the headphone output jack.

Without anything plugged into my amps phono sockets there is a tiny amount of noise, you really can barely hear it with your ear right on the tweeter.

As soon as its plugged into the TV there is electrical noise, it doesn't seem like a ground loop because its not a constant hum plus the amp and tv are in the same socket so no such loop exists. It just sounds like EMI or similar. its not volume related, just a set level of noise.

When watching TV with zero volume the noise is audibly louder when SD channels are selected compared to HD channels.

I know most would just suggest a DAC... I've tried this...zero noise! but it seems to "sterilise" the sound to me, similar to comparing CD to vinyl, it also added a small time delay that drove me mad watching films. Only the more pricey DACs seem to come with time delay functions.

so, can anyone suggest anything to tackle this noise issue?
Worth trying a ground loop isolator??
  Reply With Quote
Old 19th May 2017, 04:53 PM   #2
diyAudio Member
 
Join Date: Jan 2013
Location: Oregon City, Oregon
"phono sockets". If this is a true phone input, that's the wrong place to plug your TV in. Phone input is in th millivolt range, while "line" input is 1 to 2 volts. Plug into an AUX or TAPE input.
  Reply With Quote
Old 19th May 2017, 05:06 PM   #3
diyAudio Member
 
scottjoplin's Avatar
 
Join Date: Dec 2015
Location: Penrhyndeudraeth
No RCA output on the TV? Is the noise on headphones?
__________________
What came first, the music or the misery? Nick Hornby https://www.youtube.com/watch?v=nSlleE9s9gI
  Reply With Quote
Old 19th May 2017, 05:14 PM   #4
onis_uk is offline onis_uk  United Kingdom
diyAudio Member
 
Join Date: Jul 2004
Location: uk
The only two audio outputs are the toslink optical and the headphone jack.

Not sure about the headphones, i'll try them out and report back, I'm guessing because of the high impedance this noise would be massively reduced......?
  Reply With Quote
Old 19th May 2017, 06:14 PM   #5
Did it Himself
diyAudio Member
 
richie00boy's Avatar
 
Join Date: Nov 2003
Location: Gloucestershire, England, UK
Could be that the TV has a class-d headphone amp and when you plug an amplifier in the carrier gets modulated down or causes other oscillation in the amp.
__________________
www.readresearch.co.uk my website for UK diy audio people - designs, PCBs, modules and more.
  Reply With Quote
Old 19th May 2017, 06:37 PM   #6
onis_uk is offline onis_uk  United Kingdom
diyAudio Member
 
Join Date: Jul 2004
Location: uk
Yes, it's present with headphones too!

It sounds like my TV has a tiny R2D2 inside it lol!

Worth getting something like the Mpow Ground loop isolator?? or even try to clean up the power supply AC with a Tacima CS947?
  Reply With Quote
Old 19th May 2017, 06:38 PM   #7
cbdb is offline cbdb  Canada
diyAudio Member
 
Join Date: Oct 2008
Location: Vancouver
Use a DAC. Almost all video sound is multichannel. At least 5.1. What your listening to is a down mix to 2 channels. Would you down mix stereo to mono? Check your tv for audio delay adjustment. What you want to delay is the video to match the DAC processing delay.
  Reply With Quote
Old 19th May 2017, 06:41 PM   #8
cbdb is offline cbdb  Canada
diyAudio Member
 
Join Date: Oct 2008
Location: Vancouver
If you hear it with headphones it's not ground loop. And if it changes with picture it's probably video processing noise (digital) leaking into the audio path.
  Reply With Quote
Old 19th May 2017, 06:45 PM   #9
russc is offline russc  England
diyAudio Member
 
Join Date: Mar 2011
Location: W Yorkshire
Why would there be noise on headphones but not on TV speaker?
  Reply With Quote
Old 19th May 2017, 07:07 PM   #10
DF96 is offline DF96  England
diyAudio Member
 
Join Date: May 2007
Quote:
Originally Posted by jplesset
"phono sockets". If this is a true phone input, that's the wrong place to plug your TV in.
When a Brit says "phono" he may be referring to what Americans call 'RCA'.

Quote:
Originally Posted by onis_uk
I know most would just suggest a DAC... I've tried this...zero noise! but it seems to "sterilise" the sound to me, similar to comparing CD to vinyl, it also added a small time delay that drove me mad watching films.
Some TVs have an adjustable time delay. It would need to be a rather bad DAC to deliver sound which is worse than a TV, but there is no accounting for taste.

Quote:
plus the amp and tv are in the same socket so no such loop exists.
That means a small loop, not no loop.

You are probably hearing some combination of ground loop, Class D switching noise and video processing noise.
  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
Car Amp Electrical noise interference dannyjmf Car Audio 5 6th November 2011 01:50 AM
Hum, Noise, And House Electrical Grounding imfree707 Everything Else 0 15th June 2011 10:43 PM
Ground Wiring and Electrical Noise Reduction. spindre17 Construction Tips 8 6th July 2010 10:03 PM
lm3886 electrical noise eketehe Chip Amps 120 22nd April 2008 07:52 AM


New To Site? Need Help?

All times are GMT. The time now is 01:39 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
Wiki