Headphone amp grounding (w/ diagram) - diyAudio
Go Back   Home > Forums > Amplifiers > Headphone Systems

Headphone Systems Everything to do with Headphones

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 March 2007, 05:29 AM   #1
diyAudio Member
 
redrabbit's Avatar
 
Join Date: Oct 2004
Default Headphone amp grounding (w/ diagram)

I started to plan my ground wiring, and ran into a possible snag.

evolution:::
Building this amp, I put each channel on a seperate board.
Then began to think "why not use seperate power supplies?".
But there isn't enough room in my amp case, so outboard PSU(s) has become a possible solution.


SNAG:
Concidering the output jack ground....I'm confused what to do here. This one ground point must tie somewhere to both psu's/amp grounds , right? (headphone jack/cable ground is shared for both R and Left)......if this were a dual mono speaker amp..seperate grounds go to seperate speakers, no problem.
But for headphones ??
(is the headphone jack the only place the two grounds connect?....what about case, leave it floating everywhere after the transformer?

(ac input ground tied to case)

(not sure yet (and not drawn): input ground, pot ground)
Click the image to open in full size.

=FB=
  Reply With Quote
Old 15th March 2007, 04:20 PM   #2
diyAudio Member
 
theAnonymous1's Avatar
 
Join Date: Feb 2004
Location: Anonymityville
redrabbit,

This reply is in regards to your mystery SOIC in the parts and supplies forum. First, only you and moderators can reply to threads you start. Second, here is my best guess at what your mystery SOIC is.....

http://focus.ti.com/docs/prod/folder.../tlc2201a.html

=tA1=

  Reply With Quote
Old 15th March 2007, 04:33 PM   #3
diyAudio Member
 
theAnonymous1's Avatar
 
Join Date: Feb 2004
Location: Anonymityville
Hey what do you know, after actually reading your post I have something to contribute other than the above post.

I just recently built some "mono block" headphone amp boards that will also have separate supplies. I plan to tie the ground from each amp output to the headphone jack, and then the headphone jack will be electrically connected to the case. That will be my only ground point and everything else will be isolated.

Hope that helps in some way.

http://i15.tinypic.com/2z3zbxv.jpg
http://i17.tinypic.com/2rwawqd.jpg
  Reply With Quote
Old 18th March 2007, 03:28 AM   #4
diyAudio Member
 
redrabbit's Avatar
 
Join Date: Oct 2004
Thanks, O'Anonymous1....

How are you wiring your supplies?
Are you using seperate transformers, or ??

I'm a little bit intimidated here, as I've not seen any drawn schematics in my proposed setup, posted above, when powering a shared ground device - (headphones).
....I could rewire my headphone cables for dual mono, using two jacks, one for each ear can, but I won't.

I do believe that I should not use dual supplies if they are of the "floating ground" type. (mine are not, I'm using xformers with center-taps, and 3 term regulators for each leg, each supply.)
I did find a single transformer the other day, multitap 16v,0,16v and 16v,0,16v.
....choices....

=FB=
  Reply With Quote
Old 18th March 2007, 03:53 AM   #5
diyAudio Member
 
theAnonymous1's Avatar
 
Join Date: Feb 2004
Location: Anonymityville
In the first pic I posted there is one of the supplies to the right. It is a dual secondary with separate bridges. It gives me an unregulated +-30v. I'm not sure if I want to regulate it or not as the OPA551 I'm using can run at that voltage.

If you keep each channels ground separate up until the headphone jack everything should be fine. It works for me anyway. I just haven't found an enclosure for it yet so it's all just sitting in a box for now.

BTW, I don't ground the chassis to the mains ground EVER. Bad stuff.
  Reply With Quote
Old 18th March 2007, 09:55 PM   #6
diyAudio Member
 
redrabbit's Avatar
 
Join Date: Oct 2004
Quote:
Originally posted by theAnonymous1
BTW, I don't ground the chassis to the mains ground EVER. Bad stuff. [/B]
I do, but always with a 3 position lift switch:

1) Chassis to ground
2) 100nf between case and ground
3) Lifted from case

=RR=
  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
Grounding Check please (diagram included) redrabbit Solid State 10 15th October 2007 09:52 AM
headphone amp circuit diagram usinga 300b tube arvin Headphone Systems 3 21st May 2007 06:39 AM
Grounding problem of my OTL headphone amplifier ronardi Headphone Systems 1 17th May 2006 05:19 PM
LM3875 kit grounding, optimal grounding for separate amps and psu? findog Chip Amps 9 16th May 2005 10:27 PM
comments please on star grounding points for tube headphone amp jarthel Headphone Systems 13 25th June 2003 07:19 PM


New To Site? Need Help?

All times are GMT. The time now is 10:59 PM.


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