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

Twisted Pear Superior quality electronic kits

Thread Tools Search this Thread
Old 28th April 2010, 11:01 PM   #1
phrarod is offline phrarod  United States
diyAudio Member
Join Date: Aug 2005
Default BP/PS supplies - get ground from where?

While I'm waiting to upgrade to the new shunt from you guys I'm trying to redo the grounding scheme and lower my hum levels. I have a tube output in the same chassis although its ps is in another chassis.

Both chassis share the same chassis ground (connected by wire in the cable). I want to separate the digital grounds from the analog/signal grounds. I notice if I lift all the digital grounds to the AN dac board I still get reference to chassis ground coming from the Twisted Pear boards. All I can think is they're getting the ground chassis reference from the Torodials I purchased from you. I've never worked with Torodials before so I can't see with 2 wires to AC and two to the boards how they can get chassis ground reference. I have the trans mounted to the chassis using the hardware that came with it. Since there's no center tap or shield -- what am I missing?

Essentially I wanted to try to float the digital grounds to see if I can get less hum.
  Reply With Quote
Old 29th April 2010, 03:41 AM   #2
phrarod is offline phrarod  United States
diyAudio Member
Join Date: Aug 2005
ok, I found the issue after a lot of measuring. It was on the dac board. When I screw down the I/V's it makes chassis ground from the standoff. This doesn't make any sense until I realized I used the lead that also grounds the MuMetal can and put it to ground star grounds presently not connected to anything. I used plastic screws and its solved to chassis ground issue..

However, I have a couple questions.

I'm wondering of I should remove that can ground because shields shouldn't go to floating grounds as I understand it. Problem is what I just found so its either not use it or give up on the idea of floating the digital.

Since the power supplies do not see any earth ground until the hit the digital board is it ok to float this whole star ground?

I would wind up with two 'stars' one floated for the analog and a second floated for the digital which are all connected back to the chassis ground coming in from the ps box.

Just trying to drop hum to as low as possible....
  Reply With Quote
Old 5th May 2010, 03:05 AM   #3
Russ White is offline Russ White  United States
diyAudio Member
Russ White's Avatar
Join Date: Jan 2005
Location: Nashville, TN, USA
It is perfectly fine to float the whole thing.
Less pulp more juice Twisted Pear
/Twisted Pear Audio Blog
  Reply With Quote
Old 5th May 2010, 04:03 AM   #4
phrarod is offline phrarod  United States
diyAudio Member
Join Date: Aug 2005
Thanks Russ. I did and reduced him by 85% or better. Now I'm greedy.

My dac board has Analog out grounds which my i/v use. I have the i/v secondary grounded to my analog grounds but the input are the board's which are floated with the rest of the digital. Do you think I should move those grounds to the analog?
  Reply With Quote


BP/PS supplies - get ground from where?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

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Bench PS: stacking DC supplies ErikdeBest Equipment & Tools 2 6th March 2009 03:00 PM
Help Convert Bryston BP-20 PS from 230v to 115v ainami Solid State 5 12th December 2008 07:01 AM
4 Amplifiers on 1 PS? Ground problem geminni Solid State 12 27th April 2007 09:22 AM
A/D Ground plane separation and common supplies rtarbell Parts 1 16th August 2006 04:05 AM
About this PS Design and Ground Scheme aborza Solid State 4 2nd December 2002 02:29 AM

New To Site? Need Help?

All times are GMT. The time now is 04:59 AM.

Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 15.79%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Copyright ©1999-2018 diyAudio