This is not a change, but the basic design.
Read the whole thread (I know, a lot of work
) and you will find that the design is scalable. If you increase the supply voltage you will get more output power, more power dissipation and you will need more fets to be paralleled. The 12V version is fine with just one output device per leg.
---
Holger
Read the whole thread (I know, a lot of work
) and you will find that the design is scalable. If you increase the supply voltage you will get more output power, more power dissipation and you will need more fets to be paralleled. The 12V version is fine with just one output device per leg.---
Holger
Thank you, Holger, for your response.
I did follow the thread but found a bit difficult as I am new to this subject and from time to from maybe need some more elaboration. 
Thank people like you to bring the rest of us to a higher level 
and appreciate poeple like you who do not just do 
to the rest of us who are a little behind.
I still have the question on the rail voltage.
In Grey's original design there was one output device per leg either but 15V was used. If there are no other reasons, why not just keep the 15V in the latter version?
I did follow the thread but found a bit difficult
as I am new to this subject and from time to from maybe need some more elaboration. Thank people like you to bring the rest of us to a higher level and appreciate poeple like you who do not just do to the rest of us who are a little behind.I still have the question on the rail voltage.
In Grey's original design there was one output device per leg either but 15V was used. If there are no other reasons, why not just keep the 15V in the latter version? 
I've been reading this thread since day one. I've seen PCB layouts/artwork, but I haven't seen anyone offering to have these boards produced. Maybe I missed it? Is there any chance someone might have 50 boards made and sell them, a la BrianGT/Harvardian in another thread? Or a company, such as the Czech company that produces the blue boards for other Aleph designs, which might offer them?
Yes Nelson,you are right,it is not the right thing to get for a DIY project...!
But I think about getting a backlightened Vu meter for bias indication,I find it cool on the face plate,and if you have a problem inside you see it from the faceplate...not with a nasty smell in the room or little bits of TO247 ejected at you!!!...If I am fast enough,I can reduce volume or running to switch of the amp...DIYaudio can be a sport,isn't it?
Regards
Anael
But I think about getting a backlightened Vu meter for bias indication,I find it cool on the face plate,and if you have a problem inside you see it from the faceplate...not with a nasty smell in the room or little bits of TO247 ejected at you!!!...If I am fast enough,I can reduce volume or running to switch of the amp...DIYaudio can be a sport,isn't it?
Regards
Anael
Well, you could design a high Impedance current sensing control circuit easily enough. Even use an off the shelf Honeywell circuit, connect the output to a relay that cut's power to the supply rails. You could even shunt the rails across a load resistor and disconnect the mains at the same time to eliminate any thump.
Oh how about redundant devices, if a transistor fails, current swing causes a similar circuit to flip the rail to the other device. When the failed FET stops conducting it trips a logic gate which turns on a LED telling you which device has failed.
or you could........
What were we talking about?
Anthony
Oh how about redundant devices, if a transistor fails, current swing causes a similar circuit to flip the rail to the other device. When the failed FET stops conducting it trips a logic gate which turns on a LED telling you which device has failed.
or you could........
What were we talking about?
Anthony