Mikelandjelo, this amplifier from Silicon Chip is actually Sigma amp from Dr Bora Jagodic. You could find a lot of usefull facts on Serbian forums and on Dr Bora's site. I have a feeling that you understand Serbian.
dobrivoge, the basic design is straight from Hitachi's application note for the first generation TO3 audio power Mosfets, back around 1979. Almost every application simply copied or adapted it and some still do, 30+ years later. I think you'll find that except for small details, Boraomega's Sigma design does too.
FYOI, the Silicon Chip designer's first Hitachi clone using this basic design could have been back in 1981, with more published kit versions in between.
FYOI, the Silicon Chip designer's first Hitachi clone using this basic design could have been back in 1981, with more published kit versions in between.
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Good feeling....I already read all what Dr Bora Jagodic wrote and did.Original design and his version too has few issues with heat on resistors.....and some transistors.I made my own version which works cold....only output transistors r getting hot when output power is rising.On +/-64,5V i have pure sine wave peak to peak of 120V ----- from 64,5V i have 60V available on speaker.My version is bug free .... and i personaly designed protection which is making this amp bullet proof.I made my own problem with ground design anyway.....PCB design which i uploaded here is corrected PCB which is silent.....I have 1-3,5mV noise on output ..... same as i short my scope probe.....I mean its so good that when u turn it on u cant know is it on if you dont look at LEDs.If u put ear on any speaker u cant hear anything , absolutly ....So now i have to make stereo system 🙂
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I think in today's world, this isn't a major criteria anymore. A large number of designs on this forum are totally silent ! The issue probably becomes noticeable only when you start using speakers with very high efficiency like typically the + 99 db/watt types.
Not sure what you ask, but if you think we are the same person, no.
Bora is Doctor, Master and Man of the World. His nick on this forum is Boraomega.
I'm just rookie DIYer.
I'm so big rookie that I can't see any difference between SC amp from first post and Sigma.
Bora is Doctor, Master and Man of the World. His nick on this forum is Boraomega.
I'm just rookie DIYer.
I'm so big rookie that I can't see any difference between SC amp from first post and Sigma.
So which one is original?..... SC or Sigma?I am glad that u r expirienced DIYer.If u have Skype send it to me via PM.I like to be in touch with skilled engeneers.I like how it turns out with amplifier after i made few changes anyway......I tested frequency responce and on lower frequencies i made it to have slightly higher gain.....up to 200Hz.....and then from there i made it to be little lower and flat till 25KHz....I am really satisfied with sound.
No, we don't understand each other.
Rookie means newbie, beginner, pocetnik.
You had a problem and I wanted to help pointing on Serbian forums where some people made Sigma amplifier. They are experienced, not me.
A "borrowed" circuit and a "secret" protection circuit while asking for help on DIY ?
Little benefit to others and seems a bit "shady".
Art M u r tha man.Yes i borrowed all .... probably as u do always 🙂 .For me all discussions in this topic r finished.I dont have anything to prove to anyone.All what i wrote is truth and it will be as i said.U can try all what u want but i will never ever share circuitry that i have designed.Thank you all and bye till next time.
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