1. This line uses the DC boost line power supply DC12V can be boosted to more than 120V power supply; single DC12V1A (DC12V1A), the current is not limited, the voltage does not exceed 16V preamplifier; voltage amplification 5 times, amplification is a little big, hear the distortion can be reduced in moderation volume 2. Pre-stage working condition: full-frequency output, full-frequency output does not exist there is a lack of any frequency, if you hear the high and low frequency which is less, please check your equipment preamp sensitivity: up to an effective 3V is not distorted! 3. Tube preamplifier is a class A amplification state (that is, the preamplifier is always amplified state), the signal line is recommended to use with shielding, otherwise it may produce interference with the sound and so on! 4. High-quality materials, experience enhanced audio fidelity, restore true sound. Stable product performance, upgraded for a variety of models of bile ducts. Preamplifier frequency response 5HZ-500KHZ, as long as your ears can hear the frequency through the preamplifier is the same as can be heard 5. The preamplifier has a toggle switch with three adjustable , which you can freely adjust according to your own preferences and audio settings. Wide range of applications, support for any low-level signal inputs Power supply:DC12-16V Current: equal 1A Instructions for use: 1. Locator with switch:twist the knob clockwise to "tick" a light, then the volume is the minimum,continue to twist clockwise to increase the volume 2. tube filament:tube to be inserted in , boot to see the tube filament light red, note that the backlight is also red, to tube filament light machine to operate 3. Audio output input:near the power connector side is the output,the output should be connected to the amplifier or active speakers,the input to the audio source: such as cell phones,CDs,computers,,MP3 and other low-level signal inputs 4. DC input, using DC3.5/5.5x2.1 socket 5. Left and right channel inputs are audio signal inputs that can be connected to low-level signal inputs 6. The left and right channel outputs are audio signal outputs,which can be connected to the audio signal inputs of amplifiers or active speakers. 7. Before this stage with amplification function, if your audio source itself with noise, it will amplify the noise that comes with the audio source, so please use a good audio source test! 8. The product we have been rigorously tested to that there is no problem before the issue of the machine does not come with the noise, if you encounter the above problems can be excluded from the test method Colour:As Shown Material:Metal Package Contents: 1 * Tube preamplifier Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm. 1. This line uses the DC boost line power supply DC12V can be boosted to more than 120V power supply; single DC12V1A (DC12V1A), the current is not limited, the voltage does not exceed 16V preamplifier; voltage amplification 5 times, amplification is a little big, hear the distortion can be reduced in moderation volume 2. Pre-stage working condition: full-frequency output, full-frequency output does not exist there is a lack of any frequency, if you hear the high and low frequency which is less, please check your equipment preamp sensitivity: up to an effective 3V is not distorted! 3. Tube preamplifier is a class A amplification state (that is, the preamplifier is always amplified state), the signal line is recommended to use with shielding, otherwise it may produce interference with the sound and so on! 4. High-quality materials, experience enhanced audio fidelity, restore true sound. Stable product performance, upgraded for a variety of models of bile ducts. Preamplifier frequency response 5HZ-500KHZ, as long as your ears can hear the frequency through the preamplifier is the same as can be heard 5. The preamplifier has a toggle switch with three adjustable , which you can freely adjust according to your own preferences and audio settings. Wide range of applications, support for any low-level signal inputs 1. This line uses the DC boost line power supply DC12V can be boosted to more than 120V power supply; single DC12V1A (DC12V1A), the current is not limited, the voltage does not exceed 16V preamplifier; voltage amplification 5 times, amplification is a little big, hear the distortion can be reduced in moderation volume 2. Pre-stage working condition: full-frequency output, full-frequency output does not exist there is a lack of any frequency, if you hear the high and low frequency which is less, please check your equipment preamp sensitivity: up to an effective 3V is not distorted!