Nobsound&reg; 2014 latest 6N9P+EL34B single-ended class A tube amplifier 13w*2 Rated output power: 13W*2 standard connection; Frequency Response: 20Hz - 26KHz Total Harmonic Distortion: &lt;1% (1kHz); Input Sensitivity: 500mV-2v Input impedance: 100K; Output Impedance: 4, 8; SNR: 88dB Rectifier tube: 5Z3P  1 / preamp tubes: 6N9P  2 / power tubes: EL34B  2 Dimensions (W  D  H): 350  230  160mm; Weight: about 11Kg; Power supply:110V(115V) / 50~60HZ