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

Pass Labs This forum is dedicated to Pass Labs discussion.

threshold s/450e bias
threshold s/450e bias
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 21st November 2019, 05:39 PM   #11
Nelson Pass is offline Nelson Pass  United States
The one and only
 
Nelson Pass's Avatar
 
Join Date: Mar 2001
threshold s/450e bias
Yes, we want the voltage across the resistors.

And be careful, that's 78 volts...
  Reply With Quote
Old 21st November 2019, 09:00 PM   #12
elwood625 is offline elwood625  United States
diyAudio Member
 
elwood625's Avatar
 
Join Date: Jan 2013
Location: Elkhart Lake, WI
You may want to buy the rubber high voltage gloves technicians use on electric/hybrid cars. You can find them at most electric supply stores.
They are bulky and uncomfortable, your hands will sweat inside them, however, it sure beats accidentally touching 78 vdc, That kind of early retirement is not what it's cracked up to be.
__________________
ACA v1.6 monoblocks, Balanced Zen Line Stage, M2x, B1 Korg triode, 12AX7a Phono amplifier, Balanced B1 Korg triode, 6FG6 "Magic Eye" tube VU meter
  Reply With Quote
Old 21st November 2019, 11:29 PM   #13
miguelnoda is offline miguelnoda  Spain
diyAudio Member
 
Join Date: Oct 2009
Default threshold s450e

What voltage do I have to have in each of the 1ohm resistors?
  Reply With Quote
Old 22nd November 2019, 12:05 AM   #14
Nelson Pass is offline Nelson Pass  United States
The one and only
 
Nelson Pass's Avatar
 
Join Date: Mar 2001
threshold s/450e bias
Quote:
Originally Posted by miguelnoda View Post
What voltage do I have to have in each of the 1ohm resistors?
I would start with .1V and see how hot that gets the amp.

And you can use the following guide to get to 50 deg C.
Attached Images
File Type: jpg CRIKEY HOT.jpg (39.5 KB, 93 views)
  Reply With Quote
Old 22nd November 2019, 11:25 AM   #15
miguelnoda is offline miguelnoda  Spain
diyAudio Member
 
Join Date: Oct 2009
Default threshold s450e

thanks for helping me but I'm a little lost
Where do I have to take a voltage as a reference and what should it be?
I have the temperature probe.
  Reply With Quote
Old 22nd November 2019, 11:26 AM   #16
Zen Mod is online now Zen Mod  Serbia
Official Court Jester
diyAudio Member
 
Zen Mod's Avatar
 
Join Date: Jan 2003
Location: ancient Batsch , behind Iron Curtain
threshold s/450e bias
post pictures and it'll be shown
__________________
my Papa is smarter than your Nelson !
clean thread; Cook Book;PSM LS Cook Book;Baby DiyA ;Mighty ZM's Bloggg;Papatreasure;Papa...© by Mighty ZM
  Reply With Quote
Old 22nd November 2019, 05:26 PM   #17
Nelson Pass is offline Nelson Pass  United States
The one and only
 
Nelson Pass's Avatar
 
Join Date: Mar 2001
threshold s/450e bias
There are a bunch of 1 ohm resistors on the output stage. Each of them has
two wires coming out at the end. The DC voltage is between one of those wires
and the other.
  Reply With Quote
Old 2nd December 2019, 12:40 AM   #18
miguelnoda is offline miguelnoda  Spain
diyAudio Member
 
Join Date: Oct 2009
Default Threshold s450e

I already have it set at 45 degrees Celsius and it is perfect.
Now I have to adjust a T200 that I don't have the adjustment values.
Thanks for the help
  Reply With Quote
Old 2nd December 2019, 08:45 AM   #19
marcomariutto is offline marcomariutto  Italy
diyAudio Member
 
Join Date: Feb 2014
Just got a couple of SA-2 that run a bit cold to the touch.
I am planning to inspect them and adjust the bias if needed.
Would anyone be able to confirm that 150mV is the correct value for the voltage drop across the emitter resistors?

Thank you in advance for any help.
Marco
  Reply With Quote
Old 2nd December 2019, 09:45 AM   #20
baeijsman is offline baeijsman  Denmark
diyAudio Member
 
Join Date: Mar 2015
Location: Copenhagen
threshold s/450e bias
@ Marcomariutto: Correct! I have attached a picture from the manual.
Attached Images
File Type: jpg S_SA_bias.jpg (179.8 KB, 32 views)
  Reply With Quote

Reply


threshold s/450e biasHide 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
threshold s/450e miguelnoda Solid State 2 20th November 2019 11:06 PM
Threshold S500 optical bias - filter caps and bias - experience so far eswaroop Pass Labs 9 13th April 2019 05:57 PM
Threshold S/500 bias set up anyone? stevieg123 Pass Labs 31 24th August 2016 06:31 PM
Bias adjusting on Threshold SA4/e Mywing Pass Labs 19 10th June 2010 04:35 AM
Threshold SA4/e bias nchelazzi Pass Labs 2 16th June 2008 09:10 PM


New To Site? Need Help?

All times are GMT. The time now is 11:53 AM.


Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 14.29%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
Copyright ©1999-2019 diyAudio
Wiki