Go Back   Home > Forums > Amplifiers > Solid State

Solid State Talk all about solid state amplification.

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 3rd August 2010, 11:34 AM   #111
diyAudio Member
 
jan.didden's Avatar
 
Join Date: May 2002
Location: Great City of Turnhout, Belgium
Blog Entries: 7
This is the Safe Operation Area curve. You can see that at the moment the Vce reaches 100V, the max allowed IC is about 500mA.
This needs to be coupled with the phase shift of a speaker load which will draw appreciable positive current even with Vout=0 or negative, so you can get the situation that Vce is larger than Vsupply and STILL the transistor has to deliver current.

It's hard to predict the max phase shift of a speaker; often designers use 45 or 60 degree as design worst-case value. It can all be calculated but it takes a bit more than this post. So, be conservative, and for 100V supply use LOTS of output devices in parallel. Or, maybe someone here can do the calculations.

jd
Attached Images
File Type: jpg 5200 soa.jpg (55.7 KB, 445 views)
__________________
Never explain - your friends don't need it and your enemies won't believe you anyway - E. Hubbart
Check out Linear Audio Vol 7
!
  Reply With Quote
Old 3rd August 2010, 11:40 AM   #112
AndrewT is online now AndrewT  Scotland
diyAudio Member
 
Join Date: Jul 2004
Location: Scottish Borders
and Fairchild shows <=900mA @ 100Vce for a single shot, non-repeating, 100ms pulse.
__________________
regards Andrew T.
  Reply With Quote
Old 3rd August 2010, 11:42 AM   #113
diyAudio Member
 
destroyer X's Avatar
 
Join Date: Feb 2004
Location: Recife - Brasil Northeast
Default I see....so, it is not safe...have worked with 98 volts positive and negative

over 8 ohms...when voltage drop is not that big.... had produced almost 500 watts, during one hour, with 5 output pairs..and it is not safe.

Not safe means that will burn?..... or means that will burn because the SOA wants to burn?

This is in the internet Janneman, now a days these informations are open to everyone to read.

Transistor Safe Operating Area

You are saying that is not good this way.... that is not safe..and i am saying real world have worked with many times more than 500 mA.... what is the meaning of this discussion?... want to prove my amplifier burned when it have not burned or the SOA was wrong to my samples (magic ones maybe).

Enjoy to predict things dear Janneman..i use to build, to test and to be sure.

regards,

Carlos
__________________
SELENIUM!... Brazilian brand of speakers factory tour; https://www.youtube.com/watch?v=v6khSy9HShQ; https://www.youtube.com/watch?v=S52ju-sTwzg

Last edited by destroyer X; 3rd August 2010 at 11:47 AM.
  Reply With Quote
Old 3rd August 2010, 11:53 AM   #114
diyAudio Member
 
jan.didden's Avatar
 
Join Date: May 2002
Location: Great City of Turnhout, Belgium
Blog Entries: 7
Quote:
Originally Posted by destroyer X View Post
over 8 ohms...when voltage drop is not that big.... had produced almost 500 watts, during one hour, with 5 output pairs..and it is not safe.

Not safe means that will burn?..... or means that will burn because the SOA wants to burn?

This is in the internet Janneman, now a days these informations are open to everyone to read.

Transistor Safe Operating Area

You are saying that is not good this way.... that is not safe..and i am saying real world have worked with many times more than 500 mA.... what is the meaning of this discussion?... want to prove my amplifier burned when it have not burned or the SOA was wrong to my samples (magic ones maybe).

Enjoy to predict things dear Janneman..i use to build, to test and to be sure.

regards,

Carlos
Carlos I have no intention to continue this discussion. It's your responsibility, you do what you want.

jd
__________________
Never explain - your friends don't need it and your enemies won't believe you anyway - E. Hubbart
Check out Linear Audio Vol 7
!
  Reply With Quote
Old 3rd August 2010, 11:58 AM   #115
diyAudio Member
 
destroyer X's Avatar
 
Join Date: Feb 2004
Location: Recife - Brasil Northeast
Default Thank you dear Janneman...i also do not like discussion

I want to be happy, to continue to enjoy life and to use the Safe Operational Area in this place you can see here....limiting space to dance, with this charming blonde.

Be happy, and welcome to my soa:

YouTube - Riu Palace Aruba Salsa Dancing

I am now busy, dreaming to dance with her.

Carlos
__________________
SELENIUM!... Brazilian brand of speakers factory tour; https://www.youtube.com/watch?v=v6khSy9HShQ; https://www.youtube.com/watch?v=S52ju-sTwzg

Last edited by destroyer X; 3rd August 2010 at 12:02 PM.
  Reply With Quote
Old 3rd August 2010, 12:26 PM   #116
diyAudio Member
 
eesbiboi's Avatar
 
Join Date: Apr 2010
Location: cebu, philippines
Default ...parts replacements...

Quote:
Originally Posted by eesbiboi View Post
carlos,

sir...
i believe some trannies are not locally available in our place or might just be very hard to find...
just in case what are the replacements for this trannies below???


BC 546 BP = ?
BC 818-40 = ?
MJE 15032 = ?
MJE 15033 = ?

can i use 2sc5200/2sa1943 instead of MJL 1302A/MJL 3281A???

salamat,
regards...

it's a hard discussion you got for a day...or was that arguement???...
with lots of engineers...
anyway, anyone would like to answer my question???...
  Reply With Quote
Old 3rd August 2010, 12:40 PM   #117
diyAudio Member
 
ostripper's Avatar
 
Join Date: May 2008
Location: Albany , NY (smallbany)
Quote:
Originally Posted by destroyer X View Post
Worked!...i cannot understand what you mean...sorry...maybe i am not skilled and i have to make it burn because theories.

You may be kidding...i will remember to laugh about latter.

regards,

Carlos
I do REAL WORLD tests everyday with my primary amp. With only 4 output pairs and 2 pairs of speakers in parallel, my drivers (MJE15032/3) get HOT during parties and other occasions. I have used this amp for over 13 months , it does not lie IN THE REAL WORLD.

My greatest concern is for safety , namely at 100V or even 70V with a 1KVA+ trafo. I send the kids outside and stand away from a power supply like this as through it was a BOMB. My other concern is the drivers .... nowhere enough SOA to last 13 hours much less 13 months.

Of course it may work for a hour. Even on that tiny junk heatsink. Physics must be different in S. america because even 250 watts makes for toasty warmth on my HUGE .05 C/w stealth heatsinks. NO ONE could never market or even call this thing a 1KW amplifier without using the Rob Elliot 117 method or one of the other ones I suggested.

At this deadly power level , to overdesign is more important than anything.

Quote:
By janneman - Carlos I have no intention to continue this discussion. It's your responsibility, you do what you want.
It might be ours , too. I will say to everybody ,DO NOT BUILD THIS !!! IT IS JUNK and dangerous.

With just a few more transistors you could have a real safe amp that would last for years. The willingness of many other forum members to accept DX's misguided advice here and on his many other threads reflects the fact that there are MANY accidents in the waiting. My suggestion is for them to read Bob cordell's many interviews and other very valuable info available at DIYA.

I have just recently read all the DX threads and was aghast at the MAJOR quantities of outright dangerous misinformations contained within. I could start a whole new thread to discount these outright lies there are SO MANY.

This is not a personal attack , Carlos ..just a reality check for someone who has publicly accused me of stealing other forum members designs (DX original or symasym) , shown a unwillingness to discuss ANY changes or substitutes in your designs (all stolen) and publicly stated that I have no originality. Not all of us have access to BC-xxx transistors. I am very reasonable and will accept truths if they are explained in a civil manner and I WILL NOT HESITATE to point out something that is wrong.
OS
__________________
Mongrel website , always current and updated :
http://www.fidelityforce.com/ostripper
  Reply With Quote
Old 3rd August 2010, 12:45 PM   #118
diyAudio Member
 
destroyer X's Avatar
 
Join Date: Feb 2004
Location: Recife - Brasil Northeast
Default I am not an engineer dear Eesbiboi, and sometimes i feel glad i am not

Replacement suggestions.

This BC840 is the one reduces a lot distortion..but you can try a bigger one, alike MJE340/350.

To the drivers and CCS, you can use other transistors able to dissipate 10 watts and units that can face 200 volts or more from colector to emitter..there are millions of units you can use....current will not be the problem...and even the smaller one in To220 case will be able to face that current or more.

To the drivers you can even use the same transistors you use in the ouput..they can work fine there too, despite some small loss in gain...also i have used the power transistor as CCS to drivers.

BC546/556 can be substituted by 2N5401/5551 and other million of models, ancient and new models.

The output transistor may be units that can operate with more than 200 volts from colector to emitter, units able to face 5 amperes or more from colector to emitter, units to dissipate 100 watts or more.... so, these one you mentioned will fit...and other thousand transistors will fit too.

I am not the best one to suggest options of transistors, but at least i have tried to help...let's listen others....wait a little bit to see if other suggestions will be posted...as these guys are crazy to help..you see how they have jumped in the thread?... crazy to help maybe...we gonna see that soon.

Discussions man...people do not read the thread and come to discuss....i was already very damned with my amplifier and was screaming with the amplifier..saying why he have not burned when Mr. Soa arrived.

ahahahahahah!

Here we do not earn money..but at least we have lots of fun!

Dear Eesbiboi, i have a lot to do, and i cannot stay here for too long..will let you with these folks that for sure will work hard to help you.

Carlos
Attached Images
File Type: jpg mad with my amplifier!.jpg (190.7 KB, 432 views)
__________________
SELENIUM!... Brazilian brand of speakers factory tour; https://www.youtube.com/watch?v=v6khSy9HShQ; https://www.youtube.com/watch?v=S52ju-sTwzg

Last edited by destroyer X; 3rd August 2010 at 01:01 PM.
  Reply With Quote
Old 3rd August 2010, 12:59 PM   #119
diyAudio Member
 
ostripper's Avatar
 
Join Date: May 2008
Location: Albany , NY (smallbany)
Quote:
Originally Posted by eesbiboi View Post
it's a hard discussion you got for a day...or was that arguement???...
with lots of engineers...
anyway, anyone would like to answer my question???...
My point exactly , Carlos WILL NOT DISCUSS any part substitutions or changes to (HIS ??) designs . EESBIBOI ... don't build this one , google ESP AUDIO project 117 and build that.

As far as part substitution , one must always make other changes (emitter degeneration Resistors and other design considerations).I would suggest you proceed very carefully considering the fact that you even asked these questions concerning substitutions.

BC 546 BP = ? 2sa992/2sc1845 family
BC 818-40 = ? You really would not want to use this (VCeo of 40?? SMD??)
MJE 15032 = ? 2sc4793
MJE 15033 = ? 2sa1837

Just get datasheets , compare Ic , Vceo , Hfe , take a peek at the evil SOA plot , aim for + 10-20%

As far as the outputs.. YES , don't waste your money , build ESP project 117 and be happy. happier , happy - est
OS
__________________
Mongrel website , always current and updated :
http://www.fidelityforce.com/ostripper
  Reply With Quote
Old 3rd August 2010, 01:07 PM   #120
diyAudio Member
 
ostripper's Avatar
 
Join Date: May 2008
Location: Albany , NY (smallbany)
Quote:
Originally Posted by destroyer X View Post
Replacement suggestions.

This BC840 is the one reduces a lot distortion..but you can try a bigger one, alike MJE340/350.

To the drivers and CCS, you can use other transistors able to dissipate 10 watts and units that can face 200 volts or more from colector to emitter..there are millions of units you can use....current will not be the problem...and even the smaller one in To220 case will be able to face that current or more.

To the drivers you can even use the same transistors you use in the ouput..they can work fine there too, despite some small loss in gain...also i have used the power transistor as CCS to drivers.

BC546/556 can be substituted by 2N5401/5551 and other million of models, ancient and new models.

The output transistor may be units that can operate with more than 200 volts from colector to emitter, units able to face 5 amperes or more from colector to emitter, units to dissipate 100 watts or more.... so, these one you mentioned will fit...and other millions of transistors will fit too.

I am not the best one to suggest options of transistors, but at least i have tried to help...let's listen others....wait a little bit to see if other suggestions will be posted...as these guys are crazy to help..you see how they have jumped in the thread?... crazy to help maybe...we gonna see that soon.

Discussions man...people do not read the thread and come to discuss....i was already very damned with my amplifier and was screaming with the amplifier..saying why he have not burned when Mr. Soa arrived.

ahahahahahah!

Here we do not earn money..but at least we have lots of fun!

Dear Eesbiboi, i have a lot to do, and i cannot stay here for too long..will let you with these folks that for sure will work hard to help you.

Carlos
BC840 / 2n5401 / Mje340-50 ... totally different devices to apply to this circuit. to use each in the current mirror will change the gain of the circuit which will have to be changed each time with the change in device. It would not be recommended to swap out devices in an unimformed way with a amplifier that is this deadly.

READ this .. Project 117

OS
__________________
Mongrel website , always current and updated :
http://www.fidelityforce.com/ostripper
  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
zeta 500 watts n-channel amp pcb need ashokavarthanan Solid State 0 1st October 2007 03:10 PM
Fender/Sunn SA6520P 6 channel powered mixer 520 watts dhardinger Instruments and Amps 0 12th April 2007 11:10 PM


New To Site? Need Help?

All times are GMT. The time now is 09:52 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