TUBE A937 Hifi Digital Preamp Tube Amplifier Buffer 6J1 Audio Tube Preamplifier DC12V

TUBE A937 Hifi Digital Preamp Tube Amplifier Buffer 6J1 Audio Tube Preamplifier DC12V                                    

6 major features of valve preamplifier:
The valve amplifier has its own “valve taste”, with warm and classic sound, good sense of music, good atmosphere, its significant advantage is the sweet and soft sound, natural concern, particularly its extent of great dynamic range and good linearity can be easily substituted by other devices.
1. A wide range of combination and strong applicability: It can be combined with all audio signals available in the market: power amplifier and active speaker with analog and digital signal input, etc.
2. Classic valve 6J1 design: It adopts the classic valve 6J1 design, optimized circuit, the valve design is exchangeable, which produces soft, sweet and mellow sound.
3. Power conversion module: The product adopts AC-DC power design, DC12V power source, available for universal application.
4. Prominent workmanship, highlight personal style: The product adopts the all-aluminum shell through CNC technology.
5. Use boost mode, high-voltage power supply: Better than common power supply mode, AC100V-240V
6. Soft tone, mellow vocal base, sweet and warm, transparent and classic.

Description:
A937 is a high-performance portable mini-sized valve signal preamplifier, sound quality processor, built-in high-performance boost processor and signal amplifier, with respect to circuit design, it assigns I/O signal processing and amplification function to the most classical valve 6J1. This valve is specifically used for high-performance audio system design, with ultra-low harmonic distortion, low noise, high gain bandwidth and other features. Dual FET input provides a wider dynamic range, as well as audio signal amplification and bipolar circuit for the valve.

The valve sound enhancement processing technology can correct and restore signal loss and phase deviation caused by the audio signal system due to various reasons, thus faithfully reproducing sound, making listener feel enriched bass and treble, the sense of positioning, clarity and brightness are close to the ideal scene effect, the addition of audio signal enhancement circuit to acoustic system will make the sound more beautiful, bring about the enhanced sense of depth, fineness and clarity, fine treble, transparent and mellow tenor, natural and mellow bass, as if listener is placed on the scene.

Valve signal preamplifier is mainly used for signal input, e.g.: computer, cellphone, tablet, game console, TV set, TV box, MP3, signal source output device and other signal input, product I/O uses the universal RCA interface, audio signal amplification switch. The product has a wide range of application, which is applicable to any kind of signal input device, or alternatively used as signal preamplifier, the power supply and signal uses the boosted module for implementing voltage isolation technology, and applies high-precision Taiwan made potentiometer for balancing and calibration, with extreme high degree of positive/negative voltage balance. Additionally, it has high-capacity professional filter capacitor for filtering, and the power supply is considerably clean. Signal amplification is cleaner.


Note: In case of product noise, it may be caused by:
- The valve is not properly inserted, carefully examine to insert the valve again, please properly insert the valve in power-off state.
- The product is a preamplifier with signal amplification, if the audio source has noise, it may amplify the noise of audio source, please appropriately use the audio signal playing.
- For noise caused by poor quality of signal line or poor power filter, alternatively exchange the signal line or use the power supply for audio signal playing.
                                                                       
Specification:   
- Classical valve 6J1 parameter heater-type oxide cathode ultra-sharp cut-off pentode:
- Filament voltage: 6.3V, current: 0.17A
- Plate voltage: 120V, current: 7.35mA
- Second-grid voltage: 120V, current: 3.2mA
- Transconductance: 5.2mA/V
- Cathode resistance: 200Ω
- Input impedance: ＞12k
- SNR>100dB
- THD+N: 0.0003%
- Audio I/O: RCA stereo jack
- Power supply: DC12V
- Net weight: 286g
- Product with package weight: 447g
- Product dimensions: 99.1mm(L) X 95.1mm(W) X 30mm(H)

Packing list                            
- 1 X A937 Valve Amplifier
- 1 X 100-240V AC adapter (DC12V),power cord is 100CM