Tube Headphone amp Ayon HA-3 II Class of Operation Pure Class A, SE-Triode Tube Complement 2 x AA45 Mesh, 2 x 12AU7 S/N Ratio > 100dB (unweighted) Input Impedance 50 kΩ Frequency Response at 32Ω 15 Hz – 35kHz Harmonic Distortion (at 150mV ) < 0.01% Channel Separation L/R > 89dB...