PSU shunt capacitor selection - diyAudio
Go Back   Home > Forums > Amplifiers > Tubes / Valves

Tubes / Valves All about our sweet vacuum tubes :) Threads about Musical Instrument Amps of all kinds should be in the Instruments & Amps forum

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 January 2008, 10:04 AM   #1
oshifis is offline oshifis  Hungary
diyAudio Member
 
Join Date: Mar 2004
Location: Budapest, Hungary
Default PSU shunt capacitor selection

I have a preamplifier based on 4 identical SRPP stages per channel (E88CC ~ 6DJ8). Recently I replaced the coupling capacitors to PIO and I am thinking of replacing the B+ shunt capacitors close to the tubes, as well. I read somewhere that the SRPP topology is sensitive to power supply quality, because it has very low PSRR. Now, the main capacitors are 1000 uF/450 V flash electrolytics (two per each tube), and I use WIMA MKS-4 1 uF/630 V capacitors next to the tubes. Would it give any audible improvement if I replaced them to PIOs? I have some spare 0.22 uF/400 V PIO capacitors, are they not too small? B+ is around 310V, and Io = 5 mA per tube. The load resistance calculated from these is 62 kohms. The time constant would be then 13.6 ms, giving a corner frequency of around 12 Hz. The shunting of the capacitor is effective above this frequency. Is this correct? Please advise.

Thanks,

Laszlo
  Reply With Quote
Old 21st January 2008, 10:31 AM   #2
oshifis is offline oshifis  Hungary
diyAudio Member
 
Join Date: Mar 2004
Location: Budapest, Hungary
Well, I decided to try and listen to the Russian PIOs (K42-Y2, 0.22 uF 400V) in the weekend. The difference is surprising...
  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
Coupling capacitor selection DcibeL Chip Amps 23 18th July 2011 04:20 AM
PSU capacitor selection phreeky82 Parts 3 28th June 2006 09:33 AM
Help with Capacitor selection for amp gengis Solid State 9 18th April 2005 04:16 AM
Aleph4 capacitor selection Jmertz Pass Labs 3 3rd May 2002 06:48 PM


New To Site? Need Help?

All times are GMT. The time now is 08:25 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