JJ EL84 power valve
Classic British-design, easily overdriven for distortion
From the factory formerly known as Tesla, these JJ valves are my preferred choice in modern valves. I stock ECC83S (a 12AX7 with a spiral filament), and various power valves.
Out of stock
Note: (April 2022: the Russian invasion of Ukraine and the sanctions have disrupted the global supply of valves. Therefore, only the version without valves is available until further notice.).