Salas hotrodded blue DCB1 build - Page 133 - diyAudio
Go Back   Home > Forums > Source & Line > Analog Line Level

Analog Line Level Preamplifiers , Passive Pre-amps, Crossovers, 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 7th September 2011, 12:59 PM   #1321
diyAudio Member
 
Join Date: Oct 2009
Default Balanced DCB1

Iíve managed to do some listening to my balanced dcb1 I must say that Iím really impressed. Iíve only hooked it up between a Buffalo32 dac and a balanced headphone amp. No hum of noise problems to speak of. The fact I cannot tell that itís in the signal is saying something

nycavsr2000 attached is an updated diagram that is working for me, well as least its sounding good so far.

Thanks Salas for a great project!
Some final pics for entertainment

*Wiring diagram updated to match that of post 1333 as requested.
Attached Images
File Type: jpg IMG_6095.jpg (82.2 KB, 672 views)
File Type: jpg IMG_6092.jpg (94.1 KB, 666 views)
File Type: jpg DCB1 BAL Wiring Scheme.jpg (121.3 KB, 676 views)

Last edited by johnwmclean; 7th September 2011 at 01:22 PM.
  Reply With Quote
Old 7th September 2011, 01:15 PM   #1322
Tea-Bag is offline Tea-Bag  United States
not politcally affiliated
diyAudio Member
 
Tea-Bag's Avatar
 
Join Date: Feb 2006
Location: Kennebunk
Blog Entries: 7
John, if you dont mind, I am going to grab the nycavsr2000 diagram and post it to the DCB1 BE blog. Balanced connectivity is always asked about, but not seldom seen.
__________________
Salas Boards 2014 #2 SHIPPED |F5TC board and power supplies available PM | Hot-Rod DCB1 boards and kits available PM |Mesmerize kits available (no boards)
  Reply With Quote
Old 7th September 2011, 01:17 PM   #1323
diyAudio Member
 
Join Date: Oct 2009
Your welcome Tea-Bag.

FYI the signal return on both boards are connected to ground chassis via a ground loop breaker as follows;

The ground loop breaker is a 10Ω 5W resistor in parallel with a 0.1ĶF capacitor rated at least 250VAC. For safety this capacitor should be rated for class X or Y (good for across-the-line use) with flame retardant casing.

Last edited by johnwmclean; 7th September 2011 at 01:19 PM.
  Reply With Quote
Old 7th September 2011, 01:18 PM   #1324
syklab is offline syklab  Hong Kong
diyAudio Member
 
Join Date: Jul 2009
Location: Hong Kong
Hi John,
What do you use for volume on your balanced DCB1 configuration?
  Reply With Quote
Old 7th September 2011, 01:19 PM   #1325
diyAudio Member
 
Join Date: Jan 2006
Location: Toronto
Nice looking build John.

If I recall correctly, you were running a stage 2 at 600ma. Are the mosfets staying cool enough?
__________________
Michael
  Reply With Quote
Old 7th September 2011, 01:36 PM   #1326
diyAudio Member
 
Join Date: Oct 2009
Quote:
Originally Posted by syklab View Post
Hi John,
What do you use for volume on your balanced DCB1 configuration?
Volume is controlled via a volumite controller at the DAC. Itís a simple I2C/SPI device available from Twisted Pair Audio.

Quote:
Originally Posted by mike_mcf View Post
Nice looking build John.

If I recall correctly, you were running a stage 2 at 600ma. Are the mosfets staying cool enough?
Thanks Mike, yes 600ma, after a couple of hours I measure 35įC, comfortably warm.
  Reply With Quote
Old 7th September 2011, 01:46 PM   #1327
diyAudio Member
 
Join Date: Jan 2006
Location: Toronto
Quote:
Thanks Mike, yes 600ma, after a couple of hours I measure 35įC, comfortably warm.
Very nice!
__________________
Michael
  Reply With Quote
Old 7th September 2011, 01:55 PM   #1328
AndrewT is offline AndrewT  Scotland
diyAudio Member
 
Join Date: Jul 2004
Location: Scottish Borders
Quote:
Originally Posted by johnwmclean View Post
the signal return on both boards are connected to ground chassis via a ground loop breaker as follows;

The ground loop breaker is a 10Ω 5W resistor in parallel with a 0.1ĶF capacitor rated at least 250VAC. For safety this capacitor should be rated for class X or Y (good for across-the-line use) with flame retardant casing.
I recommend a pair of diode connected inverse parallel in parallel to your Disconnecting Network (loop breaker).

This limits the voltage difference between chassis and audio ground to <700mVpk during normal operations and ~<=2Vpk during fault to earth operation. A pair of 1n4002 would do nicely.
__________________
regards Andrew T.
  Reply With Quote
Old 7th September 2011, 02:20 PM   #1329
Tea-Bag is offline Tea-Bag  United States
not politcally affiliated
diyAudio Member
 
Tea-Bag's Avatar
 
Join Date: Feb 2006
Location: Kennebunk
Blog Entries: 7
Andrew, I am having a hard time visualizing a few concepts you mention.

'disconnecting network' -what are we disconnecting?
Also - inverse parallel in parallel to .....

I am lost a bit on this too. I use a CL60 if needed, but mine is not balanced.
__________________
Salas Boards 2014 #2 SHIPPED |F5TC board and power supplies available PM | Hot-Rod DCB1 boards and kits available PM |Mesmerize kits available (no boards)
  Reply With Quote
Old 7th September 2011, 02:34 PM   #1330
AndrewT is offline AndrewT  Scotland
diyAudio Member
 
Join Date: Jul 2004
Location: Scottish Borders
Many of the earlier implimentations of the impedance between the Safety Earth on the chassis and the Audio ground were referred to as Disconnecting Network. I adopted this phrase because I could see that it avoided the misleading use of earth "loop breaker".
Many interpret that phrase as breaking the connection from Audio Ground to Safety Earth.
Some commercial gear even have a switch to allow this to be selected.
Some commercial gear have two connections from Audio Ground. One direct to chassis and the other via a resistor, labeled "hum reducer".
I'll stick with "Disconnecting Network" to avoid those ambiguities.

Join two traces with a diode. Now connect a second diode in parallel. There are two ways to add that second parallel diode. True parallel or inverse parallel.
Inverse parallel allows AC and DC current to pass in both directions with a maximum voltage drop (Vdrop) of Vf for the diode. This is usually given in the datasheet and can vary from 400mV to a couple of volts depending on the current passing.

If one uses a CL60 as the sole component in the Disconnecting Network, then try to determine Vdrop when Fault Current passes from Audio Ground to PE.
I don't know how to test that a CL60 is safe for all fault conditions.
I have tested inverse parallel diodes and know they are safe. See my report from a couple of years ago.
__________________
regards Andrew T.

Last edited by AndrewT; 7th September 2011 at 02:36 PM.
  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
dcb1 buffer with shunt reg. merlin2069er Swap Meet 0 3rd August 2010 05:25 PM
F2 and DCB1 parts selection - please advice! DQ Pass Labs 6 25th November 2009 03:20 PM
Y B Blue - how blue LED improves the CD playback Peter Daniel Digital Source 176 25th September 2003 07:40 AM


New To Site? Need Help?

All times are GMT. The time now is 01:12 AM.


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