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

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 8th March 2004, 12:45 AM   #1
K-amps is offline K-amps  United States
diyAudio Member
 
K-amps's Avatar
 
Join Date: Nov 2003
Location: Indiana
Default Curious power Cap question.

Gentlemen,

Heads up, stupid question here:

Typically in a linear dual rail power supply, you'd have at least 2 power lytics after the bridges. Each one will have one prong ref to Gnd and the other on the positive or negative rails right?

Now if I want to add capacitance, I will simply paralell more caps and voila.

Here is my question: I have recently got some surplus 200V 7400 uF caps and I want to add capacitance to by BJT amp (based on an Adcom 555ii.)

Can I simply connect these to the +90 and -90 rails without connecting it to the ground in any way? I mean these caps will see 180v and not 90v...

I know it will simulate 4 times the capacitance if I had connected it in series with reference to ground, (conventional way) but my concern is, will I cause some kind of rail disbalance and blow the amp?

The main caps are already in circuit, these will just be add-ons... I know 200v caps are costly hence no one uses them in this configuration but since I have them, I thought I'd ask the question...

thanks in advance,

-K
  Reply With Quote
Old 8th March 2004, 01:34 AM   #2
K-amps is offline K-amps  United States
diyAudio Member
 
K-amps's Avatar
 
Join Date: Nov 2003
Location: Indiana
Picture attached of what I am trying to do.

C3 is the cap I want to add to the amp's current PSU, (which already have C1 and C).
Attached Images
File Type: jpg curious cap.jpg (76.7 KB, 284 views)
  Reply With Quote
Old 8th March 2004, 03:25 AM   #3
The one and only
 
Nelson Pass's Avatar
 
Join Date: Mar 2001
It will work, but when did the 555 get 90 volt rails? This will
lower the ripple voltage, but will not do such a great job adding
to the capacity at very low frequencies.
  Reply With Quote
Old 8th March 2004, 11:58 AM   #4
K-amps is offline K-amps  United States
diyAudio Member
 
K-amps's Avatar
 
Join Date: Nov 2003
Location: Indiana
Quote:
Originally posted by Nelson Pass
It will work, but when did the 555 get 90 volt rails? This will
lower the ripple voltage, but will not do such a great job adding
to the capacity at very low frequencies.
I hopped it up.

I used the MJ21193/4's as outputs and the MJL21193/4's as drivers. I kept the input and VA stages fixed at +/-85vdc. My next step is to up the rails to +/-95vdc.

1) Curiously Nelson, why do you say it will not add much capacitance to the lower end.. but more importantly whta frequencies do you think will begin to suffer.
2) What if I remove C1 and C2.... I will have a dead amp right?

PS: I am surprized no one else replied and you took it upon yourself to do so (My gratitude) but I would have thought its a pretty basic question...
  Reply With Quote

Reply


Hide this!Advertise here!

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
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
Creek 4330 ...curious power inside redrabbit Solid State 3 26th December 2007 05:11 PM
Curious CARTRulz Subwoofers 3 13th June 2006 01:40 AM
Just a curious question... needtubes Subwoofers 19 16th May 2006 01:53 AM
Curious Madmike2 Digital Source 3 19th September 2005 08:48 PM


New To Site? Need Help?

All times are GMT. The time now is 04:53 AM.

Page generated in 0.06547 seconds (81.02% PHP - 18.98% MySQL) with 11 queries

Copyright ©1999-2012 diyAudio