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EL84 SE Amplifier

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Hi Alex, this is my amplifier with 6sl7 and el84, output transformer is a 10 watts and it plays in triode mode up to 4 watts with 10% THD, at 2 watts it is 0.7%
 

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Congratulations! But maybe something is wrong in driving of output stage. This power is for SE, your PP power must be about 10 W. Have You scope and sin. generator to measure PP signal on output of phase spliter on both plates and output stage? Maybe mode of phase spliter is wrong?
 
No, it is not, the quoted wattage is perfectly normal for PP triode EL84
Ou....but You use 250 V in triod /if autobias and U on the OT, +U on the tubes will be less 240-230 V/....Why You don't use triod in SE - cl.A with power 2 W and sounding will be for level better? I don't doubt Your sound is good...When I made first my amp, I think it is the top of the ice cream.....
You amp is good idea for very sensitivity speakers...I like 1 W amp like my SE clA triod EL11 Telefunken /I think the best penthod ever known/ with very good OT with band wider 20-40000 Hz. And it sounds better my 300B - SE.
 
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I think, where is reason use complete PP 2 W with 3 tubes, if SE 2 W with 1 and 1/2 tubes is much better about sounding /1 W with speaker 96 dB sounds like 10 W/, IMO....People use PP only for big power /for breaking sinks :)/, for speakers with low sensitivity,... sound is sharp and metal, except good bass...and no more....but this is another beer.
 
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