Description Topping A50S Desktop Headphone Amplifier View Topping Product Manuals >> Features 4.4mm Balanced Output 0dB and 6dB Step Gain setting NFCA Modules <0.00007% THD N 144dB DNR <0.3uVrms Noise <0.1 Ω Output Impedance 3500mW x2 Maximum Output Power 2 step gain settings, adapt to various sensitivities A50s is equipped with two gain settings of 0dB/6dB at SE output(6dB/12dB at balanced output). Wide range of gain settings and the 0.3uVrms ultra-low noise makes A50s easily adapt to all types of headphones from extremely sensitive IEMs to most power demanding full-sized over-ears. Also an excellent preamp The NFCA modules of A50s are not only able to drive the headphones but also apply to be a preamplifier with the same ultra-high performance. When it is in preamp mode, output impedance is as low as 20ohm, which is widely suitable for various devices. 2 step gain settings, adapt to various sensitivities A50s is equipped with two gain settings of 0dB/6dB at SE output(6dB/12dB at balanced output). Wide range of gain settings and the 0.3uVrms ultra-low noise makes A50s easily adapt to all types of headphones from extremely sensitive IEMs to most power demanding full-sized over-ears. Also an excellent preamp The NFCA modules of A50s are not only able to drive the headphones but also apply to be a preamplifier with the same ultra-high performance. When it is in preamp mode, output impedance is as low as 20ohm, which is widely suitable for various devices. HPA/PRE automatic switching When the A50s is not connected to any headphones, it automatically works in the preaplifier mode, and the amplified signal is output from the RCA on the back panel. When the headphone is connected to 6.35mm or 4.4mm output, A50s automatically switches to the headphone amp mode, and lhe signal is only output to the 6.35mm and 4.4mm jack. Ultra-High Performance NFCA balanced modules A50s uses the same NFCA (Nested Feedback Composite Amplifier) module from flagship A90. Voltage Current hybrid feedback architecture along with UHGF (Ultra High Gain Feedback) technology provides excellent DC and AC performance. High output current drive capability allows the amp driving low impedance headphones with ease. Ultra-low noise of 0.3uV is miles ahead of the competition, giving an absurdly high dynamic range of 144dB and no audio noise and darkest background for the most sensitive IEMs. Full Aluminum case A50s uses full aluminum case with unique workmanship. The outer casing is made of an aluminium brick through CNC precision machining. The outer casing is designed with thermal conductive column to dissipate heat from the power supply and OP-AMP through the entire outer casing. 6.35mm SE & 4.4mm balanced output Although there is only a single-ended input, A50s has a built-in balanced amp circuit. Therefore, it can drive single-ended headphones by 6.35mm output, and drive balanced headphones by 4.4mm balanced output. Wide range of adaptation to headphones A50s has a high voltage swing of 42Vp-p, power of 3500mW per channel when both channels are driven and output impedance of less than 0.1 Ohm. It easily drives power-hungry headphones with a wide range of different impedance. When the A50s is not connected to any headphones, it automatically works in the preaplifier mode, and the amplified signal is output from the RCA on the back panel. When the headphone is connected to 6.35mm or 4.4mm output, A50s automatically switches to the headphone amp mode, and lhe signal is only output to the 6.35mm and 4.4mm jack. Ultra-Hih Performance NFCA balanced modules A50s uses the same NFCA (Nested Feedback Composite Amplifier) module from flagship A90. Voltage Current hybrid feedback architecture along with UHGF (Ultra High Gain Feedback) technology provides excellent DC and AC performance. High output current drive capability allows the amp driving low impedance headphones with ease. Ultra-low noise of 0.3uV is miles ahead of the competition, giving an absurdly high dynamic range of 144dB and no audio noise and darkest background for the most sensitive IEMs Full Aluminum case A50s uses full aluminum case with unique workmanship. The outer casing is made of an aluminium brick through CNC precision machining. The outer casing is designed with thermal conductive column to dissipate heat from the power supply and OP-AMP through the entire outer casing. 6.35mm SE & 4.4mm balanced output Although there is only a single-ended input, A50s has a built-in balanced amp circuit. Therefore, it can drive single-ended headphones by 6.35mm output, and drive balanced headphones by 4.4mm balanced output. Wide range of adaptation to headphones A50s has a high voltage swing of 42Vp-p, power of 3500mW per channel when both channels are driven and output impedance of less than 0.1 Ohm. It easily drives power-hungry headphones with a wide range of different impedance. Specifciations THD N @ 1kHz A-wt 6.35mm Headphone jack <0.00007% @ Output=850mW(32Ω) <0.00006% @ Output=90mW(300Ω) THD N @ 1kHz A-wt 4.4mm Balanced Headphone jack <0.00007% @ Output=3.4W(32Ω) <0.00006% @ Output=367mW(300Ω) THD @ 20-20kHz 90kBW 6.35mm Headphone jack <0.0004% @ Output=720mW(32Ω) <0.0002% @ Output=77mW(300Ω) THD @ 20-20kHz 90kBW 4.4mm Headphone jack <0.001% @ Output=2.88mW(32Ω) <0.0005% @ Output=307mW(300Ω) SNR @Max Out 1kHz A-wt 6.35mm Headphone jack 137dB SNR @Max Out 1kHz A-wt 4.4mm Headphone jack 143dB Dynamic Range @1kHz A-wt 6.35mm Headphone jack 138dB Dynamic Range @1kHz A-wt 4.4mm Headphone jack 144dB Frequency Response 20Hz-200kHz(±0.05dB) Output Level 6.35mm Headphone jack 21Vpp Output Level 4.4mm BAL Headphone jack 42Vpp AP measured noise level @A-wt 6.35mm Headphone jack <0.7uVrms @G=L <0.8uVrms @G=H AP measured noise level @A-wt 4.4mm BAL Headphone jack <0.9uVrms @G=L <1.1uVrms @G=H Actual noise level* @A-wt 6.35mm Headphone jack <0.3uVrms @G=L <0.45uVrms @G=H Actual noise level* @A-wt 4.4mm BAL Headphone jack <0.6uVrms @G=L <0.95uVrms @G=H Channel Crosstalk @1kHz 6.35mm Headphone jack -86dB Channel Crosstalk @1kHz 4.4mm BAL Headphone jack -128dB IMD CCIF@(18kHz 19kHz) -116dB IMD SMPTE @(60Hz 7kHz) 6.35mm Headphone jack -110dB, SMPTE4: 1 -118dB, SMPTE1: 1 Input Sensitivity 7.5Vrms@G=0dB 3.8Vrms@G=6dB Gain 6.35mm Headphone jack 0.0dB @G=0dB 6.0dB @G=6dB Gain 4.4mm BAL Headphone jack 6.0dB @G=0dB 12.0dB @G=6dB Output Impedance 6.35mm Headphone jack <0.1Ω Output Impedance 4.4mm BAL Headphone jack <0.2Ω Output Power THD N<1% 6.35mm Headphone jack 1.4W x 2 @32Ω 192mW x 2 @300Ω Output Power THD N<1% 4.4mm BAL Headphone jack 3.5W x 2 @32Ω 760mW x 2 @300Ω Output Power @2Vrms IN 6.35mm Headphone jack 485mW x 2 @32Ω 52mW x 2 @300Ω Output Power @2Vrms IN 4.4mm BAL Headphone jack 1950mW x 2 @32Ω 208mW x 2 @300Ω Load Impedance >8Ω
