61 years ago I heated my home with a Hi-Fi Valve/Tube amplifier kit but it was class-AB, not class-A.
To keep the distortion low the output tubes needed replacements every 3 months.
I soon replaced it with a solid state Hi-Fi FM receiver (not available as a kit) that still works 58 years later.
"Hi-Fi" and Tubes do not go together ........
Are You looking for the particular type of Distortion that Tubes normally create ?
You can duplicate this "Tube-Distortion" in a reasonably close manner using Solid-State Components,
if you're interested in some Circuit ideas just ask .......
If you're looking for the highest Fidelity that You can get,
high-end-Op-Amps can't be beat,
and they're readily available, and super-easy to work with.
If you're looking for the "Cool-Factor" of Tubes ...........
mount the Tube(s) of your choice on your Chassis and Power-up the Filament(s),
get the Chassis Chrome-Plated, and polished to a mirror-like finish,
then build an Op-Amp Amplifier, inside the Box, that actually processes the Signal(s).
Then watch your friends get "blown-away" by all that "pristine" Tube-goodness !!!
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