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Old 30th January 2016, 04:01 PM   #1
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Default yuor opinions please

Hello
Searching the NET project 2A3 se I found the below
Jeremy Epstein's Free Lunch
it has built some of the forum? what are your opinions? if you decide to the manufacturers who should be the secondary of power transformer
Thank you

Last edited by tasos25; 30th January 2016 at 04:08 PM.
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Old 30th January 2016, 04:25 PM   #2
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I haven't built the "free lunch" but I have built many "monkeys" (see Epsteins's page for the distinction.) Unless you build it exactly as Epstein did with the exact same power supply, these are not really beginner projects since they can require some juggling of resistor values and computations to figure out the needed values.

They are extremely clear sounding once you get the thing working properly thanks to the two stage design and the direct coupling. I would not suggest the 6C45P and battery bias for a beginner either. You would be better off with a the 6DJ8 family and LED bias; but again some engineering is required to get the amp to function at its best.
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Old 7th February 2016, 06:28 PM   #3
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Here is an amp I built several years ago. The choke is by Electra Print although any choke with 100H at 15mA will work. Naturally the choke DCR will become part of the computation for the 2A3 bias resistor. This amp uses the 6N23P which works fine, but I found it far inferior in sound quality to the triode connected E180F (I am traveling and don't have the most recent schematics with me). So to build this amp you will have to be able to compute the two resistors in the cathode of the 2A3 to ensure both the 6N23P and 2A3 work in their most linear region.
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Old Today, 06:26 PM   #4
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Quote:
Originally Posted by Palustris View Post
Here is an amp I built several years ago. The choke is by Electra Print although any choke with 100H at 15mA will work. Naturally the choke DCR will become part of the computation for the 2A3 bias resistor. This amp uses the 6N23P which works fine, but I found it far inferior in sound quality to the triode connected E180F (I am traveling and don't have the most recent schematics with me). So to build this amp you will have to be able to compute the two resistors in the cathode of the 2A3 to ensure both the 6N23P and 2A3 work in their most linear region.

Hello
I would like to ask what we use resistors to the cathode of 2a3(Watt).How much mA go through 2a3?

Last edited by tasos25; Today at 06:42 PM.
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