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Interstage Couple 300B 811-3 SE amp

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Hi,

recently I was diy two SE tube amp.

1. 6EM7 IT ( interstage) 300B or 811-3.
THis will had class A 8W to 12W.

2. EC52--Plate Choke loading>>capacitors couple>>300B.


EC52 was a very good tube which was flattened oxide coated cathode and the gold grid wire. Amplification factor 60
Max operating frequency 300MHz. THis tube will detail & it can use one step magnification & directly drive 300B.
Worse was this tube Anode impedance 9500 ohm.

I cannot easy to use good Interstage coupling for it. Btw, I choose plate choke loading for plate of EC52 & feel good.

How about 6EM7 IT ( interstage) 300B or 811-3. THis one still under construction. But Use 6EM7 had much more different brnad tube to chose for tunning the sound! It can use both 300B & 811-3. Power output had max 12W SE. Use KT88 or EL34 ( not triode) can more or reach same power output but not triode sound.

Any comment of this two circuit.

thx

thomas




An externally hosted image should be here but it was not working when we last tested it.
 
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