The B1s is the 2nd generation of the B1, a portable amplifier which was well received across the world. With fully discrete transistors circuit design and output transistor with class-A biasing, the B1s is an extraordinary portable amplifier.
In 2014, to break the saying that “portable class-A amplifiers are impossible”, we strove to create the B1, which marked the beginning of a new era of portable amplifiers.
The B1 was the choice of over ten thousand audiophiles from around world. It received praise not only from users, but also media.
In 2015 & 2016, the B1 was on the annual recommendation list of Soomal twice in a row, and in 2016 the B1 received the award of Best Creative Technology at Guangzhou HiFi Headphones & Digital Audio Expo by ERJI.NET.
The heritage of the classic
High-quality yet affordable
Unique class-A output, mellow sounding
In addition to the high resolution, great dynamics and ultra low distortion, the B1s uses class-A amplification, giving the sound a bit of warmth and tenderness.
Powerful and portable
The B1s aims to extract every bit of potential from headphones with the rarely seen internal design of high voltage ±9V. While designing the amplifier circuits and tuning, we tested various headphones including those with high impedance and low sensitivity. The switches on the left side enable you to adjust the gain and current to fit different loads. The abundant power and excellent control make driving big cans like HD650 possible.
The perfect partner your DAP has been waiting for
DAPs have developed very fast over the years. It’s time for headphone amplifier technical specifications to better match those of today’s DAPs. The B1s, with class-leading distortion lower than 0.0002%, is the headphone amplifier your DAP has been waiting for. In fact, few DAPs have distortion that low.
Power supply is extremely important to an amplifier. The bipolar ultra-low-ripple regulator, together with the high-efficiency power supply design that enables the duration to exceed 10 hours (with current output set to 20mA), supports the B1s with constant purified power.
Typical line output indicators
Frequency response (from 10 Hz to 20 kHz): ±0.02dB
THD + n: 0.00015% @300Ω
SNR: 124dB @300Ω
Crosstalk: <110dB @300Ω
Max output: 6.443Vrms 18.4dBu(10Hz to 20kHz)
Headphone output power: @300Ω 84mW , @600Ω 42mW ,@32Ω 74mW
Class-A: 25mW/16R 50mW/32R
View of front panel
1.1 Line input
1.2 Volume control knob
1.3 Output of headphone
View of buttom panel
2.1 USB charging port(charging voltage is 5V and charging current is above 1A)
View of the left panel
3.1 Button for detecting remaining power
3.2 Detection of remaining power and charging indicator
View of right panel
4.1 Gain adjustment
4.2 Current adjustment
4.3 Power button