Im in the work of recapping a old vintage class a/b amplifier i own.
A Sonotron pa200 .
Sonotron as a brand existed only for a few years in the seventies until the production got moved and they changed the name to adyton. A name that are more known and are still known today .
while im waiting for parts i thought, why not make a schematic for it and make some posts along the way?
So said and done
My computer is not the latest model so not many drawing programs would not work, so i found digi-key's online schematic drawing program. So im learning to use it along the way too.
This project are mostly for fun, and maybe someone here have seen a similiar schematic. And maybe help me along the way . Who knows. Maybe modify it to sound better or do other things with it.
Im gonna post the llttle info i have collected over the years and updates of the progress 🙂
A Sonotron pa200 .
Sonotron as a brand existed only for a few years in the seventies until the production got moved and they changed the name to adyton. A name that are more known and are still known today .
while im waiting for parts i thought, why not make a schematic for it and make some posts along the way?
So said and done
My computer is not the latest model so not many drawing programs would not work, so i found digi-key's online schematic drawing program. So im learning to use it along the way too.
This project are mostly for fun, and maybe someone here have seen a similiar schematic. And maybe help me along the way . Who knows. Maybe modify it to sound better or do other things with it.
Im gonna post the llttle info i have collected over the years and updates of the progress 🙂


Some info about it. As the brochure says:
The signal resolution of the PA-2000 and PA-200 sets a new level for power amplifiers. Due to the symmetrical design, the choise of components and the use of a tripple power supply with torodial trans- formers, the sounding-performance can only be described as astonishing natural: A deep, tight - yet free bass that rarely has be- en heard in any amplifier system before. The extreme resolution and transient per- formance of the mid- and high end will truly set new demands on any other component used in a complete audio-system
Bolds statements . Like i said. It will be interesting to see if there is some other brand or diy guys That have used similiar design 🙂
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Wow, that brochure says this thing can do full power at one megaHertz. Seems (ahem) unlikely, but for the sake of curiousity what the heck are the output transistors?
63 transistors: .06% HD. A sim guy said my 6 transistor Apex AX6 that will put out 70 w into 8 ohms for 5 seconds sims at .06% HD.
Anyway looking forwards to a schematic that will show if there were any new tricks in the book.
Anyway looking forwards to a schematic that will show if there were any new tricks in the book.
Wow, that brochure says this thing can do full power at one megaHertz. Seems (ahem) unlikely, but for the sake of curiousity what the heck are the output transistors?
The output transistors are 2SD287 and 2SB539
Same transistors are in the Pioneer sx1050 from the same era.
amplifier for Yamaha ns10 - Page 3 - Gearspace.com
. Adyton was developed by a good friend of mine during the late 70s and early 80s, Jan Eric van der Laak, a student and later Civil Engineer educated at the Polytechnical Institute, University of Trondheim, Norway. It started with the amplifiers Sonotron PA 200 and PA 2000, a picture of which can be found by a search on the net, and it was an experience beyond belief to see how he could develop amplifiers on paper and later with components on the kitchen table, to make them sound out of this world. Due to difficulties within his company (several investors and different views), he left and founded Adyton. These were exceptionally good amplifiers - he took the Sonotron PA 2000 to the Consumer Electronics Show in Chicago in 1977, and it was classed as the World's best B-amplifier. I still have a PA 2000. He later "got a real job" but still developed Adyton, which today are high end amplifiers sold out of Oslo, Norway. Sadly Jan Eric died in 2005 at just 55 years old. ozziesollien@yahoo.com
. Adyton was developed by a good friend of mine during the late 70s and early 80s, Jan Eric van der Laak, a student and later Civil Engineer educated at the Polytechnical Institute, University of Trondheim, Norway. It started with the amplifiers Sonotron PA 200 and PA 2000, a picture of which can be found by a search on the net, and it was an experience beyond belief to see how he could develop amplifiers on paper and later with components on the kitchen table, to make them sound out of this world. Due to difficulties within his company (several investors and different views), he left and founded Adyton. These were exceptionally good amplifiers - he took the Sonotron PA 2000 to the Consumer Electronics Show in Chicago in 1977, and it was classed as the World's best B-amplifier. I still have a PA 2000. He later "got a real job" but still developed Adyton, which today are high end amplifiers sold out of Oslo, Norway. Sadly Jan Eric died in 2005 at just 55 years old. ozziesollien@yahoo.com
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