Vacuum Tube (Electron Valve) Comparison Tests The BM Amps “Valve (Tube) Comparison Tests” page presents a detailed, objective analysis of various 12AX7 vacuum tubes used in audio amplifiers. Using controlled signal testing, waveform analysis, and spectral measurements, the author compares tube brands across metrics like gain, noise, distortion (THD/IMD), and microphonics. Despite common beliefs about … Continue reading Vacuum Tube (Electron Valve) Comparison Tests