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Old 25th January 2011, 05:04 PM   #21
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Time to start paralleling devices.

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Old 25th January 2011, 05:09 PM   #22
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Thanks for the help. I am actually going to start building soon.
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Old 27th January 2011, 09:59 PM   #23
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Quote:
Originally Posted by Nelson Pass View Post
I think you can see significant improvement by simply
dropping the Jfet in on the negative side - the IRF240
on the top (aleph) side can be left as is.

To bias it properly you will need to drop the value of the
resistor from the Drain of the input transistor (and Gate
of the Jfet) to the negative rail to a lower value - I
recommend a 500 ohm pot.

wait, replace Q7 and Q8 with the semisouth R100 jfet, and R7 with a 500 ohm pot and adjust to taste?

easy/caveman/end meme

wonders what I can be generous with...

Last edited by d to the g; 27th January 2011 at 10:00 PM. Reason: cus.
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Old 28th January 2011, 01:30 AM   #24
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For this circuit I would be inclined to leave the IRFP240
on the top, saving some money and leaving some more
Vgs for the npn transistor to work with.

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Old 28th January 2011, 02:06 AM   #25
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Beginning my Aleph J mono build soon. Relying heavily on Bill for help. He has taught me what little I know. Plan to replace bottom half with SS fets, but may find it unecessary if they sound as good as I hear. F4 will be next. Already have the boards. Then pearl 2 for my brother and his crazy vinyl obsession. Going to try my best to brake the valve loose that currently holds him captive. If nothing else, maybe I can make the magic smoke
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Old 28th January 2011, 02:08 AM   #26
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Quote:
Originally Posted by Nelson Pass View Post
For this circuit I would be inclined to leave the IRFP240
on the top
Sometimes I'm a little slow, but I guess I don't understand what "on the top" means... The copyright 2005 schematic I have shows IRFP240 Q5 and Q6 on the top.
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Old 28th January 2011, 03:57 AM   #27
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that means - leave mosfets in Aleph CCS , put SS down ( to neg rail position ) and adjust Aleph CCS AC gain to your liking
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Old 28th January 2011, 01:40 PM   #28
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Quote:
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that means - leave mosfets in Aleph CCS , put SS down ( to neg rail position ) and adjust Aleph CCS AC gain to your liking
Maybe I really am slow, but that seems to lead me right back to post 23.

OH NO! A ZM vortex is pulling me in!

(or maybe i just go back to quietly trying to pick up the knowledge pieces)
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Old 28th January 2011, 02:13 PM   #29
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Quote:
Originally Posted by d to the g View Post
Maybe I really am slow, but that seems to lead me right back to post 23.

OH NO! A ZM vortex is pulling me in!

(or maybe i just go back to quietly trying to pick up the knowledge pieces)


exactly .......

or - even better - make a bastard between Babelfish J and known things from FW J2 ;

that way you'll need just one mosfet in Aleph CCS and just one SS down

ask more , if you need
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Old 28th January 2011, 02:17 PM   #30
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Does a certain tube site have hints?
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