APEX AA9
Mr. Mile,
I have added rail decoupling near the o/p device and also ground lift.
Is it recommended?
+some reduced the PCB size to 68mmx75mm
reg
Prasi
PS; many revisions, but i want to make it as good as possible.
edit: the black jumper is optional jumper to reduce the trace length from C7 to C of T6.
Mr. Mile,
I have added rail decoupling near the o/p device and also ground lift.
Is it recommended?
+some reduced the PCB size to 68mmx75mm
reg
Prasi
PS; many revisions, but i want to make it as good as possible.
edit: the black jumper is optional jumper to reduce the trace length from C7 to C of T6.
Attachments
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Thanks Mr. Mile.
I made two jumpers instead, but I'm planning to use a proper switch as soon as I connect the TB1 to amp.
Regards.
but difficult to layout..
Nice work, you can help to some diyers with Super Gainclone PCB in thread: http://www.diyaudio.com/forums/chip-amps/162099-lm3886-schematics-pcb-45.html
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You can't use the output stage diamond buffer in a power amp that way.
It's basically two symmetrical SE stages that go to current clipping very fast (if you don't bias it to pure class A) . Simple version from your sch. works for small signals but if you want to make it push-pull you'll have to use a big cap to connect the bases of output transistors. Then it will work but not very good - pair of lateral MOSFETs will do much better job, and then you get old F5-gone-BJT with addition of source follower output stage...
Hello everyone
Prasi, I finished my PCB (first version) for the AA9. Now I have to solder the components.
Regard's
That looks as good as the manufactured PCB
, nice etching!regards
Prasi
Hi, here are some measurements. I've corrected the offset by changing the 470R resistors. But I think now the amplifier is underbiased.
Advice are welcome
But the sound is very, very good. Deep, powerful bass, well balanced mids and transparent beautiful highs.
Regards Olaf
hi i also have made fx12. sounds just as olaf described, and i have vssa to compare.
how do i increase the vas current tho? change out 22k resistors or the 220ohm?
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hi i also have made fx12. sounds just as olaf described, and i have vssa to compare.
how do i increase the vas current tho? change out 22k resistors or the 220ohm?
Change 220R in VAS, use 150R or 100R.
Regards
thanks mr miles.
i can stop being impressed by this amp. deep and musically satisfying, it's the best amp for me yet, and i've built vssa and aksa clone in the past.
may we have bjt version of fx12, please?
There is EX14
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Which is the total power of the amplifier load 8R ? Thanks!
120W/8R, 200W/4R