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    Building, troubleshooting and testing of these amplifiers should only be
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    the safety precautions around high voltages.

#26 pre amp

Member
Joined 2009
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Felipe, can I do some comments?

Such a low transformer DCR not optimal for (mesh) AZ1. It would be better 100-200R DCR.
IMHO C1 low, thus output voltage also low. There are no high charging current (AZ1 unable to do so) therefore increase C1 up to 1-5uF. If output ripple bothering you, increase C3.

ps. PSUD a little cheating, output voltage about 220V, not 230.

Ps2. Attachment is my working #26 preamp (common raw PSU- each side: SSHV2- cascode CCS loaded 26 -TVC) raw HT supply.

Of course you are welcome, you are right because one time for other project I use AZ1 with other transformer with secondary DCR 83,2 ohms and was to add one resistor in series with the phase of 78 ohms or AZ1 not optimal.

Thanks for support and advices:)
 
Thanks for advice, could you elaborate so I can learn.

10H chokes have thousands of spirasl in a iron (typically) core, so you cannot use big seccion wire, or it won't fit, or it will be enourmous and very expensive.
So you use thin wire (as requested by the 30mA), so wire resistance will be a lot higher than 10Ohm. Fro experience (I build them myself) for a 10H 200mA choke resistance will be about 100Ohm and for a 10H 100mA typically about 300Ohm. For 30mA could be more.
If you make that change on the simulator you will see that output voltage and ripple are a little different.

By the way, 0,1Ohm on caps is also too low if you're using electrolitic.

Cheers
 
Member
Joined 2009
Paid Member
10H chokes have thousands of spirasl in a iron (typically) core, so you cannot use big seccion wire, or it won't fit, or it will be enourmous and very expensive.
So you use thin wire (as requested by the 30mA), so wire resistance will be a lot higher than 10Ohm. Fro experience (I build them myself) for a 10H 200mA choke resistance will be about 100Ohm and for a 10H 100mA typically about 300Ohm. For 30mA could be more.
If you make that change on the simulator you will see that output voltage and ripple are a little different.

By the way, 0,1Ohm on caps is also too low if you're using electrolitic.

Cheers

Thanks for advices, I use Bartolucci chokes are rated 10H 100mA 10 ohms, attached pic.

I'm using mkp in oil ASC X386S, attached pic.

Cheers
Felipe

P.S. How can measure lytics impedance?
 

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FINISHED!

Last photos of my implementation: The Supply Chassis!

Final result: Incredible clear #D presentation, dead quite with virtual zero noise on the speakers (even with your ear deep inside the mid/woofers).

I am very happy, the final result is really impressive.
Thanks to all (Thomas, Ale, Kevin and Rod) for your strong help and support.
 

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