Product: Reisong - A20 Hi-Fi Intergrated Amplifier KT88 Tube Single-end Class A 4ND VU Meter
Brand: Reisong

You should take about 30-100h time to operate the amp.RUN-IN to the amp gives it's best and stable sound.so during the first 100h use time the sound maybe is not the best,you can also use your own run-in method. 
 Specifications: 
Output Power: 8W * 2 (Ultra-linear connection) 
Frequency response: 20Hz-35KHz 
Output Impedance: 4,8Ω 
Total harmonic distortion: ≤ 1% (1kHz) 
Input Sensitivity: 750MV 
Input impedance: 100KΩ (three sets of input signal) 
Voltage amplification: Dawn 6J8PJ × 2. 
Power output tube: KT88 × 2. 
Rectifier tube: 5Z3PA-T × 1 
Dimensions (W×D×H): 366×300 (including knob) × 185mm 
SNR: 89dB 
Weight: about 16.5 kg (114 power transformers, export version) 
Gross weight: 18kg 
Power Supply Voltage: AC 110V-120V/50Hz-60Hz(For United States） 
 
 Features:  
With power tube current monitoring circuit, tube replacement upgrade ease. 
Medical grade 5Z3PA-T rectification. 
Imported 0.35 core output amplifier audio dedicated core, core stack thickness 86-50, A20 flux of 13,000 
Output transformer potting techniques, ensure that the output of the amplifier stability and reliability 
Double chassis design，not easy deformed. 
Output amplifier with a new imported 0.35 core manufacturing, high-purity copper wire package enameled, layered segmentation, string and connection method 
Imported 0.35 thick core manufacturing power amplifiers 
Output amplifier with high-grade stretch amplifier housing cover. 
Power Transformers: new imported 0.35, stack thickness 60MM (114-60). 
Output amplifier core: core 0.35 new imported thick high silicon (86-50). 
Japanese production of ALPS potentiometer. 
Chassis: mirror stainless steel chassis.
KT88-98 power output.
6J8P-J pre-voltage amplification.
The new power amplifier 0.35 cores do to ensure stable power supply.
Output power, maximum output power of 8W+8W.
Output amplifier uses no big loop feedback technology to ensure high sound reduction, powerful

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