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 - 12AT7, China
Chinese 12AT7 dual triode.
Vacuum Tube - 12AU7, China
9 pin miniature preamp tube (Amplification Factor = 17)
Vacuum Tube - 12AX7B, China
9 pin miniature preamp tube (Amplification Factor = 100). The Chinese 12AX7B is very similar in tone to its standard Chinese cousin, but the Bs seem to average in at slightly lower gain and noise.