Nobsound Mini Bluetooth 5.0 Valve Tube Preamp HiFi Stereo Receiver Audio Headphone Instruction Manual
- June 14, 2024
- Nobsound
Table of Contents
Mini Bluetooth 5.0 Valve Tube Preamp HiFi Stereo Receiver Audio Headphone
Thank
you very much for choosing our products!Please read this manual carefully
before using the product.
Front function description:
…………………………TF card slot- …………………………Usb interface
- …………………………IR infrared reception
- …………………………Earphone amplifier jack
- …………………………Bass knob (clockwise bass increased, counterclockwise bass decreased)
- …………………………Midrange knob (clockwise tenors increase, counterclockwise tenors decrease)
- ………………………… Treble knob (clockwise treble increased, counterclockwise treble decreased)
Top function description：
…………………………RCA work light- …………………………Bluetooth work light
- …………………………USB work light
- …………………………TFcard work light
- …………………………Switch power/channel selection key (short press to start, then short press to cut the input channel, long press to shut down)
- …………………………Prev/Volume down (short press the previous track, long press the volume down, the minimum volume RCA light flashing)
- …………………………Play/pause
- …………………………Next/ Volume down (short press Next, long press volume up, TF light flashes when volume is at its maximum)
Function description of back board:
- ……………………………Bluetooth antenna
- ……………………………Audio In（Such asCD、DAC、Mobile、TV etc，(Such as CD, DAC decoder, mobile phone, TV, etc., red to right channel input, white to left channel input)
- ……………………………Audio Out (Such as amplifier, Earphone amplifier, active speaker,red to right channel input, white to left channel input)
- ……………………………Power Plug ( DC power cann’t beyond 12V)
Functions of remote control buttons:
Standby- Enter the channel selection key
- mute
- Play/pause
- PREV
- NEXT
- VOL-
- VOL+
- number keys area
- Mode1-mode3 reserved key for function, this product has no function
Operation Steps:
- Make sure the VOL turnto theminimum
- Install the tube into the base of the tube according to the direction (the tube is not left or right, check whether the pin is deformed before installing the tube, and the deformation can be corrected by hand).
- Connect the sound source that needs to be used.
- Connect the external post equipment to the audio source output interface.
- Connect the DC12 power supply
- Turn on the power switch
- Press the tap switch to set the volume to the right level
- Bass/alto/treble can be adjusted separately.
Specifications:
| Headphone Max power output | 100mW/32Ω | THD | 0.05% |
|---|---|---|---|
| Headphone matching impedance | 16-64Ω | SNR | ≥98dB |
| Working voltage | DC 12V | Bare metal size | 12811836mm |
| Input sensitivity | 0.775V | Total Weight | 0.56kg |
| Bass/mid/treble range adjustment | ±6dB | Package Dimension | 24021060mm |
| Frequency response | 20Hz-20kHz(±3dB) | Support music format |
MP3，WMA,APE,FLAC,WAV
Frequently Asked Questions:
Q: I have all the wires connected, but no sound output?
A: 1. Check whether the work indicator is on. If it is not on, touch the on key to start the machine.After pressing the power button, the indicator light still does not go on. Replace the one with the same voltage output (it must be 12V) and test again. 2. If the indicator is on, press volume to check if the volume is too low. 3. If the above two points are normal, check whether the playback device of input audio source is paused, mute or at the minimum volume.
Q: Why is my Bluetooth range short, less than 3M?
A: The working frequency band of Bluetooth is 2.4ghz, which is consistent with the working frequency band of the router. There will be interference between each other. First, check the machines around the 2.4g HZ working frequency band.If it is still very short, determine whether the machine and the mobile phone are blocked by obstacles. If the Bluetooth is blocked, the transmission distance will be affected.
Q: Why does the sound distortion?
A:If the volume of the rear device is turned up to the maximum and the front level is also turned up to the maximum, it is easy to distortion. At this point, you just need to turn down the volume of the front or rear level.
Q: Why does the volume stay the same, but the volume is different when connected to different sources (such as a CD and then a mobile phone)?
A: The amplitude of the electrical signal varies by device. For example, a mobile phone is usually 0.35V and a CD is 1V.Natural sound levels are different.
Q: Why does the speaker make a loud buzzing sound when I plug in the input cord and don't play the sound?
Answer: used the signal line that does not take shield empty load, can have interference signal to enter amplifier to carry on amplification, if you hate this sound to suggest you replace the signal line that takes shield, perhaps unplug signal line.
Q: why the product to buy back the first step began to listen to the sound is very hard, three frequency is not very clear, but work 1 day after the normal?
A: vacuum tube is a very sensitive device, the temperature generally to reach a degree to play the best effect, so the general boot after about half an hour of preheating the sound is very natural.
Q: Can I replace the valve and upgrade?
A: yes, we have the factory test match 6j1/6j2/6j4 /6j5 / GE5654/6ak5 / 6*1 n, can directly replace, different tube voice can make a big difference.
Q: Can I replace the vacuum tube by direct unplugging?
Answer: No, it is very easy to burn out the vacuum tube, because the inside of the machine is working at high pressure, and the burning out of the hot plug vacuum tube may damage the machine.
Answer: No, it is very easy to burn out the vacuum tube, because the inside of the machine is working at high pressure, and the burning out of the hot plug vacuum tube may damage the machine.
A: At present, this model does not support phonograph/phonograph signal input, because the electric signal output value of phonograph/phonograph is very small, need to add a phonograph amplifier.
Warning:
- Please do not open the shell without permission. Improper operation may cause the danger of electric shock.
- Please use the power supply of the regular manufacturer, otherwise it will damage the machine.
- Please do not use the machine in a high temperature and humidity environment.
- Please don’t replace the tube when the power on, otherwise the tube & machine will be demaged.
- Please don’t use the non-matched tube, otherwise the tube & machine will be demaged.