• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

Single Ended 2A3/6A3/6B4G DC coupled & Transformer choices

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Ok Pieter. Here are.

Sorry guys, my english is so bad.
 

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Right. I just wanted to point that out that the lower psu only references the upper. But as a reference, it needs to be quiet, or the noise will add to the upper.

I think that if one used a "statistical regulator", it might be possible to take the gyrator reference right off the zener stack. ;)
 
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C3gT cascode gyrator loaded, direct coupled 300B SE.

BTW it's "simple", but hyper sensitive to the driver tube operating point (V1 anode voltage), so tube's aging would be destroy 300B!
 

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Some answer on e-mail questions I received:

- For "no capacitor cleaners": Instead of the last capacitors in PSU`s you can put VR tubes.

- For those who do not use C3g, you can put driver tube you want. In that case (considering the Bala comment), you can put a fuse after rectifier in the PSU for output tube B+.

Best diying.
 
C3gT cascode gyrator loaded, direct coupled 300B SE.

BTW it's "simple", but hyper sensitive to the driver tube operating point (V1 anode voltage), so tube's aging would be destroy 300B!

Actually, I think the 300b will not last as long as the c3g, but decline will not due to aging of the c3g.

I might breadboard it again with 2a3, using a statistical regulator on the lower power suppy. I think it can be designed so that even if the driver tube is pulled, it will not get destroyed.

Maybe you could use a resistor and a zener stack instead of the LND150 CCS loaded shunt... ;) and you already have a zener stack in the statistical regulator.. (oops I said too much maybe).

Ian
 
From Morgan Jones' Valve Amplifiers (4th Edition):

"The statistical regulator is certain to have >90dB ripple attenuation, so this corresponds to it tolerating 53Vpk-pk ripple post rectification."


Of course it pays to read his book in full. The circuit is not at all complex and he explains it in great detail.

Ian
 
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Specifications are sometimes cleverly "stretched".
When you take a close look at the frequency curve of your example, it is obvious that it includes the first resonance.
The real curve starts falling at about 30 kHz.


Monolith Magnetics ? - simply has to be who else specifies 7Hz - 151kHz so specifically?

THEY state very clearly that stated BW is without resonance, so how to counter that?

Knowing resonance is when Xl = Xc... looking at the (f) vs amplitude plots, how can you arrive at such a conclusion?

I suppose you know this guys math/ physics is at a very high level, Phd level, and he lectures in that/those subject/s.

There is a commercial amplifier which openly admits to using these OPT, claims measured BW out to >140kHz in circuit, retails for 25k USD

The Truth | Whammerdyne Heavy Industries

Have to say that I am leaning toward thinking that you are short on this one.


Hanze.
 
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