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

Solid State Talk all about solid state amplification.

SOA  -  What is true and what is wrong ?
SOA  -  What is true and what is wrong ?
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
Thread Tools Search this Thread
Old 12th December 2001, 01:22 AM   #1
djdan is offline djdan  Romania
diyAudio Member
Join Date: Dec 2001
Location: Romania
Dear Friends ,
This is my first thread on this forum. First of all,please forgive my bad english .

I have experience in solid state amplifiers design but something is not clear (yet) for me.

I have a very good amplifier QSC USA1310 with 16 outpout drivers MJL21194/MJL21193 per channel , and it work very
hard for 5 years (550w rms/4ohms)(+/- 80v).

I have another very good amplifier SWR SM-900 with only 4 outpout drivers 2SC3264/2SA1295 from SANKEN and it work very hard for 4 years (500w rms/2ohms)(+/- 67V)

In first case we have Imax = 16.58A (Peak Current)
In second case we have Imax = 22.36A (Peak Current)

I just saw the SOA for 2SC3264 and isn't OK becouse this driver have just 3A on 67V in DC and 10A for 10ms , single puls.

Can somebody tell me why my SWR amp don't blow yet ?

Best regards !
  Reply With Quote
Old 13th December 2001, 01:42 PM   #2
yeti is offline yeti  Germany
diyAudio Member
Join Date: Nov 2001
Location: Ewersbach
Default SOA

Hi,first of all i assume that your amplifier is a class AB type.
If the output voltage raises,the C-E Voltage of the active transistor decreaseses by the amount of the output voltage.
That means,if the transistor is fully open,it "sees"only 2or3 volts.
In addition the supply voltage decreaseses under load.
The other transistor "sees" almost the double rail voltage,but only at idling current.

  Reply With Quote


SOA  -  What is true and what is wrong ?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

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Wrong Voltage / current on BoZ... or Wrong Measuring ? gionag Pass Labs 8 14th May 2008 12:24 PM
True-RMS? star882 Parts 8 1st June 2007 03:35 AM
Is it true? rick57 Digital Source 4 31st October 2006 09:50 AM
is this true???? kathodyne Tubes / Valves 16 29th January 2006 11:26 AM
Is this true? josefr Digital Source 3 9th April 2003 10:28 PM

New To Site? Need Help?

All times are GMT. The time now is 04:36 AM.

Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 16.67%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Copyright ©1999-2017 diyAudio