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    Valve (tube) amplifier schematic help

    There certainly is a purpose. It is to create sufficient gain to amplify small signals. With 2 stages, it allows a volume control to be used toward the lower end of its range, it is how we are used to operating audio equipment. If you would like to use 2 triodes, do this, just make the...
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    Valve (tube) amplifier schematic help

    It's been a long day...
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    Valve (tube) amplifier schematic help

    First, you don't need 2 triodes. If you look at each one, you'll notice you are only using 1 triode in each tube. You can just use i tube, since it is a dual triode. You should not share the capacitor betweens pins 8 and 1. Since thge datasheet specifies about 10uF, you can't use a trimmer. Just...
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    Valve (tube) amplifier schematic help

    Using a large current through the mosfet will not give great hifi, since the linearity of the device comes into play. This called a class A power amp and requires a bit of attention to the DC bias to make it work. I can't be bothered with the specifics of this, it is more trouble than it is...
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    Valve (tube) amplifier schematic help

    This is one approach, you'll need to read the test to see what they are doing. http://www.diyaudioprojects.com/Tubes/6418-Tube-Preamp-Headphone-Kit/
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    Valve (tube) amplifier schematic help

    Generally you use a push-pull topology for the output stage. This can be discrete or a small power amplifier IC. An inefficient way is to put a lot of idle current thru the fet and reduce the source resistor to a very low value. This will flatten the battery quickly though, and need a big heatsink.
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    Valve (tube) amplifier schematic help

    No. It is N-type so the drain must be more +ve. ie to +12V with source via resistor to ground. Even with this config you would need high impedance headphones. The 100k output pot will not work very well. I don't have time right now to look up a good basic design.
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    Valve (tube) amplifier schematic help

    200 volts is a typical starting point, most amps use the main B+ at about 400 volts. The data sheet is worth reading in detail. The headphone amp only needs 1 tube and 1 Mosfet. The input grids should have series resistors at least, as the are shorted AC wise from left to right. Your stereo...
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    Valve (tube) amplifier schematic help

    I have been down the road you are on many years ago. It is very worthwhile to aspire to good distortion sounds. Generally you won’t get it from such a setup as the first schematic you presented. A plate voltage such as 9V is very low and you won’t really achieve a nice tube tone. Even with a...
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