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Old 23rd December 2010, 10:20 AM   #31
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kind regards thank u ...merry xmas
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Old 24th December 2010, 03:32 AM   #32
SKLau is offline SKLau  Australia
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Hi,

I have attached the Magus A-1 schematic for people who would like to download.

Regards,

SKLau
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File Type: jpg magus_schematic_2.jpg (565.2 KB, 360 views)
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Old 8th November 2012, 11:39 PM   #33
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Default SCHEMATIC MFA MAGAUS

Quote:
Originally Posted by SKLau View Post
I have a Magus A-1 Schematic. I think there is not a significant change in the later version of Magus B. Hope this can help.
Unfortuneately the file is too long for upload. If you want me to email it to you, send me the email address.
YOU STILL HAVE ONE
PAY YOU FOR IT

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Old 9th November 2012, 05:33 PM   #34
kevinkr is offline kevinkr  United States
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Old 11th November 2012, 02:18 AM   #35
SKLau is offline SKLau  Australia
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The Magus A-1 Schematic is already on the forum for downloading.
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Old 9th March 2013, 09:40 PM   #36
KBK is offline KBK  Canada
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"Extraordinary claims require extraordinary evidence." - Carl Sagan

Sometimes the claims aren't extraordinary. Sometimes the weakness of men's minds are the culprit.

Mass mentality has nothing to do with obviousness or truths.
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Old 10th March 2013, 06:22 AM   #37
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Default KVK: MAGUS schematic.

Espero que te sirva
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Old 24th August 2013, 04:36 PM   #38
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if you still have the schematic is it possible I could also get a copy , Thanks johnhayes at comcast dot net

Last edited by wintermute; 25th August 2013 at 12:58 AM. Reason: email change.
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Old 25th August 2013, 04:31 AM   #39
samchen is offline samchen  Taiwan
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me too please
maco0925@seed.net.tw

regards
sam
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Old 20th January 2014, 08:53 PM   #40
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Hi all,

Kind of tired from the (original) VERY high gain of my Magus B preamp and its lack of some finesse when compared to other more refined preamps I decided to mainly reduce the gain with a small dose of negative feedback to it.

And before this decision on adopting NFB I had already swaped the original tube (6DJ8) to a 6922, ECC88, 6N1P, 6FQ7 without much success: a small change here and there but the modest performance (and way HIGH gain...) was always present.

When I say modest I'm referring to the preamp behavior before I added negative feedback: I will never forget the first song I listened to when NFB was added!
MUCH better control of bass response, deeper than ever, great midrange and beautiful top extension besides now a great range for the volume control.
And a better resolution of detail...

After this point I tried again the tubes listed above and added a new one: the 6N6P which became the absolute champion of this upgrade followed by the 6FQ7.
But one can use any of the above tubes and taste his particular outcome.
Heaters supply: with 6N6P power trafo a little warmer now but no problems after a very long time...

NFB mods: very simple.
All you have to do is replace the original input resistor from 1k to 100k.
No need to remove the PCI: just cut out the 1k resistor and solder the new one (100k, each channel) to the solder pads from above.
After that a piece of the wire of your audiophile choice from output to input and a R (shrink-wrapped) resistor in series with that wire.

Feedback amount: experiment in the range suggested in the picture (R: 390k to 820k).
The smaller this resistor value the smaller the preamp gain.

If for any reason the results are not to anyone's taste everything is very simple to undo.
I guess these mods can be applied to others Magus versions, check this first, is not that difficult.

Did these mods 5 years ago, never looked back...

[ ]
Ricardo

some pictures:

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