BOSOZ PSU question - diyAudio
Go Back   Home > Forums > Amplifiers > Pass Labs

Pass Labs This forum is dedicated to Pass Labs discussion.

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 29th January 2005, 11:55 AM   #1
Tyimo is offline Tyimo  Hungary
diyAudio Member
 
Join Date: Nov 2002
Location: Hungary
Default BOSOZ PSU question

Hi!
I would like to build the BOSOZ's PSU with lower regulated voltage, ca. 40 V.

I know that: ".... It is possible to set up the power supply to regulate at lower voltages. Alternately, you might choose a single transformer that does not develop as much voltage as two D4007's. Simply replace some ofthe Zener diodes with shorting wires to produce lesser referencevoltages in increments of 9.1 Volts, or replace the 9.1 volt parts withother values....."

My question is:
-what kind of transformer is ideal for the the desired regulated 40V, if I would use 7x5.6 zenners?

Thanks

Tyimo
  Reply With Quote
Old 30th January 2005, 05:15 PM   #2
Account Disabled
 
Join Date: Aug 2002
Location: Near to the Pacific Ocean
Nelson Pass prefers the toroidal transformer.
I use a toroidal transformer for my BOSOZ, but will not hesitate to use EI type if available.
  Reply With Quote
Old 30th January 2005, 10:39 PM   #3
eLarson is offline eLarson  United States
diyAudio Member
 
eLarson's Avatar
 
Join Date: Aug 2002
Location: Gaithersburg, MD
When using lower voltage rails, you could probably scale back some of the resistor sizes from the original article, giving you higher bias current and a little higher drain voltage than with the original resistors.
__________________
Would a woodchuck bother to chuck MDF?
  Reply With Quote
Old 31st January 2005, 05:49 PM   #4
Tyimo is offline Tyimo  Hungary
diyAudio Member
 
Join Date: Nov 2002
Location: Hungary
Hi!
Thanks the answers, but I mean/ask, how many secondary voltage of the toroid need for the desired regulated 40 V?

Tyimo
  Reply With Quote
Old 31st January 2005, 05:53 PM   #5
Tyimo is offline Tyimo  Hungary
diyAudio Member
 
Join Date: Nov 2002
Location: Hungary
sorry, one more thing:
I already built the BOSOZ and it is excellent! I would like to use the PSU board for an another preamp project!

Thanks!

Tyimo
  Reply With Quote
Old 31st January 2005, 07:28 PM   #6
eLarson is offline eLarson  United States
diyAudio Member
 
eLarson's Avatar
 
Join Date: Aug 2002
Location: Gaithersburg, MD
Sorry, Tyimo... I looked back at my post and it appears to be a bit of a non sequitur.

For ~40VDC rails you could probably get by with a transformer secondary in the 30 to 32V neighborhood, presuming that you're going to use a cap-input supply and not a choke-input raw supply.

Erik
__________________
Would a woodchuck bother to chuck MDF?
  Reply With Quote
Old 1st February 2005, 05:42 PM   #7
Tyimo is offline Tyimo  Hungary
diyAudio Member
 
Join Date: Nov 2002
Location: Hungary
Erik: Thanks.
I know the x1.41 rule, but I ask for the regulated PSU voltage?
I mean: in the original article: You use 60V secondary, get 80V unregulated DC and in the end you get 60V regulated DC.
So, should I use ca. 40V secondary to get the desired 40 regulated DC?
Greets:

Tyimo
  Reply With Quote
Old 1st February 2005, 05:58 PM   #8
diyAudio Member
 
BobEllis's Avatar
 
Join Date: Sep 2003
Location: Upstate NY
Somewhere over 32 VAC would give you enough to drop ~5 volts in the regulator - about the minimum using FETs.

40 VAC will be work but watch the heat sinking of the regulator pass transistor. You'll need more than a clip on heat sink since you'll be dissipating more than 2 W if you run both channels from one regulator.
  Reply With Quote
Old 1st February 2005, 06:11 PM   #9
Tyimo is offline Tyimo  Hungary
diyAudio Member
 
Join Date: Nov 2002
Location: Hungary
Thanks Bob!
Now I see.

Greets:

Tyimo
  Reply With Quote
Old 1st February 2005, 06:14 PM   #10
Tyimo is offline Tyimo  Hungary
diyAudio Member
 
Join Date: Nov 2002
Location: Hungary
Oh, and do you mean it with 7x5.6 zenners?
  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
BoSoZ PSU Question Raoul Pass Labs 4 8th March 2005 03:44 PM
bosoz question... cowanrg Pass Labs 9 27th November 2004 02:39 AM
BOSOZ with CCS, and a question jh6you Pass Labs 11 26th March 2004 06:25 AM
BOSOZ PS Question vdi_nenna Pass Labs 5 4th August 2003 11:25 PM
Bosoz psu question protos Pass Labs 8 25th November 2002 04:39 PM


New To Site? Need Help?

All times are GMT. The time now is 11:39 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