BoyuuRange REISONG A50 MKIII 300B HiFi Intergrated Tube Amplifier Single-end Class A Valve Amp with Tube Cage
Brand: BOYUURANGE

Regarding the hum (ground noise), the vacuum tube amplifier has very high requirements for the power supply.
And it is very susceptible to interference from other electrical appliances around, especially WiFi routers.
If you have humming or other noises on both channels, you can try to turn off or remove the electrical appliances near the tube Amplifer that may affect it.
Features:
If you listen the BoyuuRange A50 MKIII Amplifier, you will know 300B is good at bass too.
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. U-shaped steel chassis thickness up to 2.4 mm thick
Output amplifier with a new imported 0.35 core manufacturing, high-purity copper wire package enameled
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: imported mirror stainless steel chassis.
Aluminum panel: high-grade aluminum CNC machining, anodic surface treatment.

Specification:
AC110V- AC120V(60Hz/50Hz)
Voltage amplification and promotion tubes: 6N8P (6SN7)x 2
Power output tube: 300Bx2 (brand PSVANE)
Rectifier: 5Z3PATx1
Output power: 7.6W x 2 (Class A) (no feedback technology)
Frequency response: 30Hz-42KHz
Output impedance: 4ohms, 8ohms
Total harmonic distortion: 1% (1kHz)
Input sensitivity: 750MV
Input impedance: 100Kohms (3 groups of input jacks)
Volume: 375 W x 290 D x 180 H mm
Packing volume: 500 W x 450 D x 290 H mm
Signal to noise ratio: 89DB
Net weight: 18 kg
Gross weight: 21 kg

Factory add an Inductance transformer and Bipolar filter circuit to get the nicer sound for the MKIII.Come with a Tube Cage and VU meters.
Power output tube: 300B × 2 (Brand PSVANE)
Power Transformers: new imported 0.35, stack thickness 60MM (114-60).
Output amplifier core: core 0.35 new imported thick high silicon (86-50).
Some of Senior audiophile optimization the electric circuit,it is better at arom,intermediate frequency and bass.