DOUK AUDIO ST-01 PRO 200W Hifi Valve Amplifier Mini Audio Receiver Bluetooth User Manual
- June 14, 2024
- Douk Audio
Table of Contents
DOUK AUDIO ST-01 PRO 200W Hifi Valve Amplifier Mini Audio
Receiver Bluetooth User Manual
ST-01 front and back panel
- VU meter
- Input channel Indicator(Bluetooth/RCA/Optical/Coaxial/USB)
- Functional knob (short press to power on/switch Input mode; long press to power off; rotate to adjust main volume)
- Bass knob
- Infrared
- Treble knob
- Bluetooth antenna socket
- RCA Input
- Coaxial Input
- Optical input
- PC-USB input
- 12 3.5mm AUX output
- 13 Speaker output(red to +/black to -, R to right speaker /L to left speaker)
- Power Interface (DC 18-30V)
ST-01 PRO front and back panel
- VU meter
- Input channel indicator(Bluetooth/U-disk/RCA/Optical/Coaxial/USB)
- Functional knob(short press to power on/switch input mode; long press to off; rotate to adjust main volume)
- Bass knob
- Infrared
- Treble knob
- Bluetooth antenna socket
- U-disk input
- RCA input(red to right channel, white to left channel)
- Coaxial input
- Optical input
- PC-USB input
- 3.5 mm AUX output
- Speaker output(red to +/ black to, R to right speaker / L to left speaker)
- Power interface (DC 18-30V)
Operation Steps
-
Insert the vacuum tubes into the sockets of ST-01/ST-01 PRO. (please check if the pins of tube are deformed)
-
Connec passive speakers to the banana speaker jacks output of ST-01/ST-01 PRO, or connect an active speaker, amplifier to the 3.5mm AUX output of ST-01/ST-01 PRO.
-
Wired input:
Connect the audio source to the input (RCA/Coaxial/Optical) of ST-01/ST-01 PRO; or connect the computer to the PC-USB socket; or Insert a U-disk to its USB socket(only ST-01 PRO supports U-disk) -
Connect the power adapter to ST-01/ST-01 PRO and then plug the power cable into the socket, and short press to turn it on, and short press again to switch to corresponding input mode.
-
Wireless Input
Please short press the functional knob to power on and then short press to switch to BT(or BT/USB) position. (blue indicator will flashing.). Turn on Bluetooth on your phone, search and click to connect, the indicator will be steady blue after successful connection.
(for Sf-Ol PRO, U-disk with priority, the input mode will automatically witch to U-disk with priority, the input mode will automatically. -
Play music on the audio source, adjust the treble/bass and main volume according to your preferences and enjoy music.
-
After use, please long press the functional knob to power off first, and then disconnect the power adapter.
-
PC-USB operation Instructions
1.Connect the ST-01/ST-01 PRO (via original USB cable) to the computer. (USB
support hot swapping)
2.Toggle the input mode switch to USB mode; Right-click on the speaker icon on
the lower right corner of computer and it will pop-up a message box, then
select the [Playback Devices]
4.Select the USB device recognized by computer in the pop-up box;
5.Set the [USB HIFI Audio] as default device.
Parameters
FAQ
Q: Why are all cables connected but there
A: 1. Check the input indicator:
- If it can light up normally, please check if the mode is selected. 2 If it cannot light up, please to detect whether corresponding input use another DC 18-30V power supply the fault is the power light is on but
- If the indicator light on on but there is no sound, so the power supply is
normal. Please continue to check according to the order of audio signal
transmission: audio signal transmission> audio source > audio cable
preamp/decoder>amplifier>speaker.
3. If all is fine, please check whether the audio source is muted, paused or the volume is too small.
Q: Why is the sound distorted? How to adjust the treble, bass and main volume?
A: Maybe the input amplitude is too large. If the volume of audio source and
ST-01/ST-01 PRO both are turned to maximum, it is easy to cause distortion.
Please turn down the volume of audio source or ST-01/ST-01 PRO. In general,
adjust the volume of amplifier to about 60%, then fine-tune the volume of
preamp (distortion will be greatly reduced in this way); the treble and bass
are usually adjusted according to the music style/ device types/personal
preference.
Q: Why does the volume of different audio sources(such as changing CD player
to phone) differ when the machine volume is unchanged?
A: Different audio devices can output different signal amplitudes, for
example, the phone usually is 0.35V, while CD player is IV.
Q: Why is the sound of power amplifier not good at first, with unclear high
frequency, but the sound is normal after working for a period of time?
A: For new speakers and amplifiers, we recommend to burn-in for at least 10
hours to get better sound.
Q: Why is there a loud market have interference, which will cause current sound.
A: 1. Please use the original power supply. Many power supplies in the
market have interference, which will cause current sound.
2. When using unshielded signal cable in no load, there will be interface
signals. Please use the shielded signal cable or unplug it.
3. If there is still noise after eliminating above situations, please confirm
whether it is external noise or internal noise. Disconnect all inputs and only
retain power supply and power cable. If the noise disappears, it is from audio
input; If the noise is still there, it is possibly caused by power supply or
the internal of product.
Q: What are the reasons for the unbalanced left and right volume of the speakers and how to eliminate them?A: Please check audio source, input cable, volume potentiometer (some amplifiers have balanced control or separate volume control of left and right channel), speaker cable, speakers (whether the position and the distance is symmetrical) and other factors.
Q: What’s the function of VU meter? What is the difference between VU meter
and voltmeter, ammeter?
A: VU meter, voltmeter and ammeter all refer to a level indication meter. Som
indicates voltage, some indicates decibels, some indicates current. And we use
VU meter to indicate the level of audio signal.
Q: Why Bluetooth cannot be searched? How to switch to Bluetooth mode?
A: Toggle the input switch on the panel or press “SELECT” button on remote
control to switch to BT mode, there will be blue light flashing, then use your
phone or tablet to search for “BT HIFI AUDIO”, click and connect it, then play
music. (The Bluetooth name may different in different models of products,
please refer to the user manual of each product).
Q: Why does the Bluetooth playback lag or even disconnect? Why is the
Bluetooth background noise/current noise obvious?
A: Please check whether the Bluetooth antenna is installed correctly, whether
there is interference or blocking (such as WiFi router / wireless telephone /
FM radio, etc., since they may be in the same frequency band as Bluetooth, and
inductive loads such as fans/refrigerators/air conditioners will also cause
some interference), whether the Bluetooth is blocked or too far away from the
device (more than 15 meters).
Q: Can ST-01/ST-01 PRO be connected to my computer via Bluetooth?
Why is there no sound when connected to PC?
A: Compared with phones, computers with poor compatibility and troublesome
operations when using Bluetooth. Need the computer with Bluetooth function and
to update the driver and set the output device to Bluetooth after connection.
Q: How long is the service life of vacuum tubes? Can I replace them by myself?
A: The service life of the vacuum tubes is about 4000-4500 hours, they are not
easy to break as long as not damaged by external forces. Before replacing,
please confirm the model that can be replaced.
Q: The vacuum tubes of ST-01/ST-01 PRO can be replaced by what models?
A: Default 6K4 vacuum tubes, can be replaced by 6J1, 6J2, 6J3, 6J4, 6J5, 6’1N,
6’4N, 6’5N, 5654/5654W, 5725, 6AK5, EF95, 6BA6, 4038, etc.
Q: What should be paid attention to when using tube devices?
A: Vacuum tube is a high-resistance component, easy to be interfered with, so
it should be as far away as possible from RF interference or electromagnetic
interference sources and avoid vibration; The tube will generate heat when
working, so it should be well ventilated and heat dissipated.
Q: USB DAC can not work after connecting with phone, is a driver required?
A: No, connect phone to USB DAC is drive-free, please check whether the phone
and the connection cable support OTG function, and some phones need to open
the OTG option and set the output device in the settings.
Q: Why is there no sound output when optical and coaxial inputs are used?
A: Please confirm the optical and coaxial of the connected device is output or
input. For example, if connected to the TV optical output, please set the
output mode and sampling rate on TV. (usually with PCM output mode option)
Q: Why is there a thumping sound when switching on/off?
A: Please confirm the on-off sequence is correct, normally it follows the
order of signal transmission when turn on: audio source→→ preamp/ DAC
amplifier speaker. (The sequence is reversed when switching off. As the
internal capacitors will be discharged for a while after shutdown. If turn off
the preamp firstly and then turn off amplifier, impact sound will be easily
caused which may damage the amplifier or speaker in severe cases.)
Q: Why is there no music output after inserting a U-disk?
A: Please confirm the format and capacity of the U-disk, as well as the file
format of the U-disk (only supports U-disk in FAT32 format within 64G).
Q: Why is U-disk playback sometimes laggy?
A: In general, MP3/FLAC/APE/WMA/WAV and other common formats are supported,
please confirm the file format of the U-disk. (Please put the music files
under root directory, don’t create a new folder or don’t play other
unsupported files, or else there may be an error.)
Warning
- Please do not open the shell by yourself, improper operation may cause a risk of electric shock.
- Please use the regular manufacturer’s switching power supply, otherwise there will be the risk of damage to the machine.
- Please do not use ST-01/ST-01 PRO in a high temperature and humidity environment.
- Please do not unplug or plug the vacuum tube when ST-01/ST-01 PRO is on, otherwise the tubes or ST-01/ST-01 PRO will be damaged.
- Please do not replace mismatched vacuum tubes, otherwise the tubes or ST-01/ST-01 PRO will be damaged.
- PC-USB input also supports mobile phones that with OTG functions, but Android system needs OTG cable and IOS system needs camera kit, please prepare by yourself. Not guarantee 100% compatible with all phones.
- When the volume is turned down to minimum, the BT/(USB) indicator will be flashing; and when to maximum, the PC-USB indicator will be flashing: At this time, the indicator of current input channel will go out but light on when the adjustment is stopped.
- ST-01 PRO with sensitivity adjustment of VU meter on its bottom, can match better with different input signals.
- Default 24V power supply, can satisfy the needs of most home speakers.
If you need higher power output, please prepare a high-quality and large power supply by yourself.
Contact information
Website: www.doukaudio.com
Email: nobsound@doukaudio.com
WeChat/Whatsapp: +86-17704028602
Address: Room 1329, Wang Cheng Building, Long Guan East Road, Long Hua
District, Shen Zhen, Guang Dong, China, 518000