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Old 4th November 2008, 10:23 AM   #61
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I'll post some more info later today
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Old 4th November 2008, 10:30 AM   #62
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Originally posted by Mooly
I'll post some more info later today
Thanks!
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Old 4th November 2008, 05:00 PM   #63
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Hi Tibi,
I have put a few notes together, in no particular order, that hopefully may help.
If you are serious of having a go I can provide help via this forum or you can email me. Maybe some others will have a bash as well.

You say you use a -/+50 volt supply. That should be OK, but if it's any higher we may have to look at replacing Q5 with something slightly higher rated.
The circuit has "two R8's" . These are so a fixed value of resistor can be fitted to set the standing current in the output stage. R 8 is initially replaced with a 470 ohm preset to adjust, then the preset is measured and a suitable fixed value fitted.
The TL071 can not be substituted. It's not in the audio path, but you will see it uses only a single negative supply. That's why you can't use anything here.
Note the polarity of C1 and C3.
R18/21 must be on the gates of the FET's if these are wired to the PCB.
The output inductor is not on the PCB. In the majority of cases it's not even needed, the 0.22 ohm provides enough isolation to prevent any stability issues.
Grounds, there are two on the PCB. Grounding is usually where it all goes wrong on DIY designs. We don't make it easy for ourselfs by building amps on separate boards but with care very good performance is achievable.
R25, the zobel resistor should be a 2 watt carbon type. Must not be inductive !
D1, the zener for the OpAmp can be a 12 volt 0.4 or 1.3 watt type.
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Old 4th November 2008, 05:01 PM   #64
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PCB, this is the view looking down on the component side.
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Old 4th November 2008, 05:03 PM   #65
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Notes
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Old 4th November 2008, 05:06 PM   #66
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I have a higher resolution image of the PCB layout ( still from the top view ) with no component overlay as this is how I print them direct onto transparancies.
If you email me can send it.
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Old 4th November 2008, 05:28 PM   #67
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What a nice design! (or have I said that before?)
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Old 4th November 2008, 05:31 PM   #68
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Thank you Lumba
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Old 4th November 2008, 05:37 PM   #69
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Default GO AHEAD !!!!

THIS IS A VERY NICE AMP !!!!

some time in th future may i have pcb from you mooly ????

when i repair my relation with mosfet may be i will built.... it looks very nice i presume that it will also play nice ....

thanks for sharing mooly !!!!!
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Old 4th November 2008, 05:37 PM   #70
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Can't wait to hear it!

I'll etch the PCB for one channel tomorrow and start putting it together.

Mooly, I sent you a PM with my email address.

Thanks,

Tibi.
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