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.

1000W PA Quasi NMOS Amp - Class H Stepdriver  possibile ?
1000W PA Quasi NMOS Amp - Class H Stepdriver  possibile ?
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 2nd July 2011, 09:25 PM   #1
NMOS is offline NMOS  Germany
diyAudio Member
 
NMOS's Avatar
 
Join Date: Dec 2010
Location: Frankfurt
Default 1000W PA Quasi NMOS Amp - Class H Stepdriver possibile ?

Does somebody have experience or ideas

I want add Class H Rail Step driver for quasicomplementary NMOS amp 60/110 V DC?


but I remember in the past some diy member told me quasicomplementary amp does not working with class H Stepdriver (amp will oscillating in negative rail and burn up) ....but I think this information is not true , because its working in commercial NAD 208 70 V / 120 V Rail

NAD 208 is commercial Class H quasicomplementary NMOS amp

I think it can work if add Class H Step driver from apex member (900 W PA amp with limiter thread )

ANY ideas to increase efficiency for NMOS amp ? I dont like BJT output stage
  Reply With Quote
Old 2nd July 2011, 09:43 PM   #2
Tekko is offline Tekko
Banned
 
Join Date: Jan 2005
Whats wrong with bjt output stages ? I say the opposite, i had a go at mosfet output but dident like the sound, maybe for a subwoofer amp but thats it.

I've also seen somewhere that for high output power, bjt is preferred over mosfets.

And i seem to prefer the sound from complementary mjt over quasi mosfet.
  Reply With Quote
Old 2nd July 2011, 09:53 PM   #3
NMOS is offline NMOS  Germany
diyAudio Member
 
NMOS's Avatar
 
Join Date: Dec 2010
Location: Frankfurt
Quote:
Originally Posted by Tekko View Post

I've also seen somewhere that for high output power, bjt is preferred over mosfets.

And i seem to prefer the sound from complementary mjt over quasi mosfet.

bjt devices cheaper is mass production by chinese manufacturer this is true

but not in sound, really... have seen many commercial poor sounding bjt amps

and often fails with secondary breakdown.


mosfets are much more rugged and free from secondary breakdown

if you want share your bjt design, and im satisfied with bjt sound it can be it changed my views but actually...bjt amp no way,... only for bass but big risk of secondary breakdown with high output power

For high current i prefer mosfets
  Reply With Quote
Old 3rd July 2011, 06:01 AM   #4
khalsa is offline khalsa  India
diyAudio Member
 
Join Date: Dec 2007
Send a message via Yahoo to khalsa
Default H CLASS

POSSIBILE
Attached Images
File Type: jpg qcpaunstablesk5.jpg (116.8 KB, 1996 views)
  Reply With Quote
Old 3rd July 2011, 10:09 AM   #5
NMOS is offline NMOS  Germany
diyAudio Member
 
NMOS's Avatar
 
Join Date: Dec 2010
Location: Frankfurt
Quote:
Originally Posted by khalsa View Post
POSSIBILE
Thank you for schematic, did you test it in real condition ?

can you send me your email adress ?
  Reply With Quote
Old 3rd July 2011, 04:22 PM   #6
khalsa is offline khalsa  India
diyAudio Member
 
Join Date: Dec 2007
Send a message via Yahoo to khalsa
HI NMOS i am not test but I now any bjt transister audio amp is working good condition no problem enjoy khalsaaudiocenter@yahoo.com
  Reply With Quote
Old 3rd July 2011, 04:49 PM   #7
Robert GS is offline Robert GS  Denmark
diyAudio Member
 
Robert GS's Avatar
 
Join Date: Sep 2005
Location: Helsingor
Quote:
Originally Posted by NMOS View Post
bjt devices cheaper is mass production by chinese manufacturer this is true

but not in sound, really... have seen many commercial poor sounding bjt amps

and often fails with secondary breakdown.


mosfets are much more rugged and free from secondary breakdown

if you want share your bjt design, and im satisfied with bjt sound it can be it changed my views but actually...bjt amp no way,... only for bass but big risk of secondary breakdown with high output power

For high current i prefer mosfets
I am very satisfied with BJT sound in my amplifiers and I haven't had any secondary breakdown yet in any of my amps sold commercially.
I have a proto type Class H doing + 2kW peak i 2 ohms with "only" 4 pair BJT and 2 switch MOSFET also tested in reactive and capacitive loads - not problem. It beated 2 x 1000W Class D RCF it was AB tested against
- so I think it's a matter of implementation

Regards,
Robert GS
__________________
GroundSound.com Active Sound - Active Listening
Digital Crossovers, Power Amplifiers and DIY modules
  Reply With Quote
Old 3rd July 2011, 05:36 PM   #8
khalsa is offline khalsa  India
diyAudio Member
 
Join Date: Dec 2007
Send a message via Yahoo to khalsa
HI GroundSound I now its tru
  Reply With Quote
Old 4th July 2011, 01:41 AM   #9
andrewlebon is offline andrewlebon  India
diyAudio Member
 
andrewlebon's Avatar
 
Join Date: Feb 2008
Default schematic

hi khalsa
greetings nice schematic can you tell schematic is of which company and values of 2sa transistors and the 2sc ones
thanking you
andrew lebon
  Reply With Quote
Old 4th July 2011, 05:14 AM   #10
khalsa is offline khalsa  India
diyAudio Member
 
Join Date: Dec 2007
Send a message via Yahoo to khalsa
transister use 2sc5200 TOSHIBA
  Reply With Quote

Reply


1000W PA Quasi NMOS Amp - Class H Stepdriver  possibile ?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
NMOS 350/500 by Quasi ID_ Solid State 127 22nd January 2017 04:39 PM
Help needed! strange sound from nmos quasi amp sanju21 Solid State 10 24th April 2012 10:03 AM
Wildcard Power Amp dev. thread (SMD, Quasi NMOS, IRFP260, digital bias) danfo098 Solid State 2 16th May 2011 09:57 PM
..About quasi class a bias for a headphone amp.. ljordan Headphone Systems 2 17th May 2005 05:19 AM
My new 1000W PA amp (pic post) matth Solid State 78 27th October 2003 10:23 AM


New To Site? Need Help?

All times are GMT. The time now is 12:56 AM.


Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 14.29%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Copyright ©1999-2018 diyAudio
Wiki