Musical fidelity A2 schematics

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Hello,
could anyone give a brief translation of what the russian and japanese guy did with their Musical Fidelity A2?
Just bought one yesterday, and I would like to improve it
Why did the russian remove the opamp, what are the benefits and backdraws?
Why such large capacitors and how are they connected?
You can find the links here:
russian
japanese
Thanks,
Sal
 
could anyone give a brief translation of what the russian and japanese guy did with their Musical Fidelity A2?

From google translate:

Japanese

http://translate.google.com/transla...tr-amp/foreign/musical/muf-a2.htm&sl=ja&tl=en

Russian


http://translate.google.com/translate?hl=en&u=http://www.zeuslab.narod.ru/MF_A2.htm&sl=ru&tl=en

Still a few mistakes in the translation but good enough to be scary. If it offered design improvements in a couple of years I would not be surprised :)
 
Salar said:
Hello,
could anyone give a brief translation of what the russian and japanese guy did with their Musical Fidelity A2?
Just bought one yesterday, and I would like to improve it
Why did the russian remove the opamp, what are the benefits and backdraws?
Why such large capacitors and how are they connected?
You can find the links here:
russian
japanese
Thanks,
Sal

jmmartins, Salar, could you give me a hand? I have an A2 also and the transformer was burnt out! I need to replace it but I don't know what the output is! there is no specification on the transformer. The schematic here is not complete so I don't know what transformer to buy. HELP!
 
Forgot to say the 2X20V AC are in full load, not open circuit where they can reach almost 2X22 V. I measured mine.
I have another toroid trafo rated 150W and it is about the same size. That’s why I said 150W. Anyway if you make some calculations you get almost the same numbers.
Be sure, before inserting the new transformer, that you don’t have a dead mosfet, otherwise you’ll get some smoke.

Good luck fixing the amp.
 
musical fidelity A2 for sale

I have on for sale in St. Louis, MO. It looks brand new. Sounds wonderful. At the moment it's getting fixed at Alpha Tech Electronics in Saint Louis. Enjoyed the thing very much running Monitor Audio stand-up speakers. Moved it to Magnapans in a medium sized room. Really enjoyed that until it quit suddenly. The same shop at the time ...

"Disassembled unit, removed entire circuit board to get access. Traced short in Power Supply section. Replaced blown rectifier and two fuses. Deoked all switches and controls. Adjusted bias voltages and thermal tested.

2-5A fuses $2.00
1 bridge rectifier $8.50

2.5 hours shop $150

Not too bad of a price, but it happened again 6 months later and I put it in careful storage. Just got it out to get it fixed for a new room, but have a greater need for a 500W subwoofer amp with low-pass. Consider all trades once it's fixed and I verify working condition. I'll send buyer picks of it setup with dB readings and smile on my face if you wish.

Travis, new to this site, want to do more diy myself. Time to start learning.
 
Status
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