Using secondary winding of a tube 12 watt Class A single ended transformer as load across speaker. Great harmonics.
It would be best to use an appropriate choke of same inductance. Using secondary of tube transformer will create high voltage on primary -- even though its not used it needs to be isolated to avoid hazard
As you need a low inductance, perhaps you can try an air cored inductor like those for crossovers.
You could load it with a high value resistor, capacitor, R/C - what does that do to the inductance of the other winding?It would be best to use an appropriate choke of same inductance. Using secondary of tube transformer will create high voltage on primary --
The inductance needs to be high -- 20 mili henry would be about right for 60Hhz low frequency range. 8/(2pi*L)
The inductive load makes it more efficient as it "kicks" above the rail more like a current source. It makes amp behave almost exactly like a tube class A.
I really think the transformer (or inductor) is responsible for most of what make a tube class A sound so good - not the tubes so much.
Power jfet will not be as efficient as the pinch off can be 12V or higher -- a low voltage threshold MOSFET is best. 6 watts output is adequate which means MOSFET no signal dissipation will be around 15 watts. Nedd good heatsinking
The inductive load makes it more efficient as it "kicks" above the rail more like a current source. It makes amp behave almost exactly like a tube class A.
I really think the transformer (or inductor) is responsible for most of what make a tube class A sound so good - not the tubes so much.
Power jfet will not be as efficient as the pinch off can be 12V or higher -- a low voltage threshold MOSFET is best. 6 watts output is adequate which means MOSFET no signal dissipation will be around 15 watts. Nedd good heatsinking
That theory is extensible -I really think the transformer (or inductor) is responsible for most of what make a tube class A sound so good - not the tubes so much.
- Autoformer volume controls that sound better than a resistor ladder
- Transformer coupled DAC output that some seem to like for some reason
- Lore has it sometimes recording engineers put signal through all-transformer coupled compressors without using compression, to improve the sound.
- Neve console mic amp plug ins with transformer coupling going in and out
- All transformer coupled amplifiers / preamps from Japan
- Manufacturers offering "magic box" type products containing 1:1 line level transformers, that customers attest to "stripping away the digital haze" or whatever.
- The signal out of every Shure SM57/58; caveat (of course) the older ones sound better having the not cost reduced...
Wife calls, cant think about it anymore.
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- Class A Guitar amp using MOSFET (or power JFET)