The first electronic amplification of sound was done with Vacuum Tubes. We have pre-amp, power and rectifier vacuum tubes among other types in New Old Stock from the golden era of American & European manufacturing as well as current production tubes from today.
Vacuum Tube - 6550A, Valve Art
Octal power tube (Max Plate Watts = 42W)
Vacuum Tube - EL34B, Valve Art
Octal power tube (Max Plate Watts = 25W) EL34B(with shadow grid) is a high performance improved version of pentode EL34A to solve the problem of overheated No. 2 Grid. Maximum anode dissipation is 25W and output power of single tube is over 10W in A1 amplification mode. When used in AB1 mode, two tubes can output over 35W. It can substitute 6CA7.