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Old 6th June 2005, 04:07 AM   #21
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main section closer view,I didn't find R11(47ohm),so I replace it to 68ohm,and R14 is 1.5Kohm,gain about 23:
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Old 6th June 2005, 04:09 AM   #22
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the PCB,I cut the line wire using a knife,is a hard work!!!
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Old 6th June 2005, 04:18 AM   #23
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and using SEC's IRF510(second hand).
I will test it tonight,god bless me!
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Old 6th June 2005, 07:57 AM   #24
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Quote:
Originally posted by Ipanema
Hi Ultimate86,

Your circuit looks like a Le' Monstre variation. Have you build those?

Regards,
Ipanema
I built a Zenquito, which is a kind of evolution with MOSFET of "Le Monstre"

http://www.bonavolta.ch/hobby/en/audio/monster.htm

l http://perso.wanadoo.fr/jm.plantefeve/home.htm

ProFet that I proposed has neither cascode nor driver !

Just Jfet input + Mosfet output ... but I do not have the complete diagram
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Old 7th June 2005, 03:43 AM   #25
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hi,all:
I test it last night.
it works abnormality ,that is to say---it doesn't works well,
result show it has about 0.5Hz surge,because first stage's low frequency gain is too strong,R3 should not connect to feedback loop,it's positive feedback...
so I decide to use other bias way(SK170's)...
look it's ac analysis graph:
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Old 7th June 2005, 04:35 AM   #26
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Take it easy!I will go on tonight,it has more suitable topology,and lower distortion...I believe it can sounds perfect!
the test in last night,I relocate R3(down end) connect to ground.
the surge problem removed,but the output point of first stage upto about 14V,no matter what,it sounds,and sounds pretty good,I can't hear any noise from the speaker,I only use one 10000uF/50V cap and shunted with one 10uF/100V MKP cap,
ouput stage's bias current is about 1A..
step by step,I walk to success...haha

this is updated version of schematic:

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Old 7th June 2005, 05:48 AM   #27
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cheers!

could you unconnect nfb and describe the sound after deconnecting?
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regards, Pawel
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Old 7th June 2005, 05:58 AM   #28
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Quote:
Originally posted by padamiecki
cheers!

could you unconnect nfb and describe the sound after deconnecting?
hello, padamiecki :
nfb???

it's hard to say that now,but I will tell you tomorrow!
regards
WINCO

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Old 7th June 2005, 05:44 PM   #29
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http://www.selectronic.fr/upload/pro...nique/4180.pdf

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Old 8th June 2005, 06:50 AM   #30
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fail again!!!
the super low surge(0.5Hz) still existing!
I suppose it's open loop gain rate is too high,and the feedback is too deep,so it occur...isn't it???
last night,after the failed testing..I had to remove the Q4 and RP3,
replace with one resistor,the value is 1Kohm...it sounds:
the sound is so soften and sweet,put my ear close to the loud speaker,about 0.3 meter(1'),I only hear the heat noise of semiconductor device..no 50Hz low frequency noise---good!
sound quality is more than my ZEN2,I hear Michael Jackson's "billie jeans"...you can lisend it for a long time,didn't feel any uncomfortable and any noisily...

I will go on!
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