Fosi Audio BL20C Bluetooth Stereo Audio Receiver Amplifier User Manual

Fosi Audio BL20C
User Manual

Thanks for choosing us!

Product Specifications

Fosi Audio BL20C is a powerful Bluetooth 5.0 HiFi stereo 2.1 channel amplifier with AUX/Bluetooth/U-disk inputs and Treble & Bass control to meet more your needs. It supports MP3/WMA/APE/FLAC/WAV music formats, suitable for most  home passive speakers. Adopting classic TDA7498E chip to get clear sound without any audible noise even at high output.

Passive Speakers
Input priority:| U-disk ＞Bluetooth = AUX
SNR:| ≥98dB
THD:| ≤0.05%
Frequency response:| 20Hz-20kHz(±3dB)
Working voltage:| 19-35V
Speaker impedance:| 4-8Ω
U-disk:| USB 2.0, compatible with
USB 3.0
U-disk capacity:| Up to 32GB, no more than 100MB per file
Support format:| MP3/WMA/APE/ FLAC/WAV
Max output power:| 160-watt x 2 @4 ohm

Product Overview & Control Functions

Front Panel

Back Panel

Package Contents

Fosi Audio BL20C Amplifier1
AC Power Cord1
24V/4.5A Power Supply 1
Bluetooth antenna1
User Manual *1

Quick Setup

Preparation
Prepare 1: BL20C, 24V power supply, passive speaker, active subwoofer, speaker wires or banana plugs, RCA cable;
Prepare 2: Make sure the volume is at a minimum.
Prepare 3: Connect passive speaker via the speaker wires or banana plugs, and connect active subwoofer via 3.5mm AUX cable, please pay attention to distinguish between positive and negative polarity.
Prepare 4: Make sure the power switch is on the “OFF” position.
Prepare 5: Connect the power supply and turn it on, the power indicator shows red light.
Note: Please make sure that the power switch is in the OFF position before connecting the power supply.

How to connect the speaker wire?
Method 1: Bare wire connection illustration

1. Release the horn terminals block terminals;
2. Insert the two ends of the speaker wire into the amplifier and speaker terminal holes;
3. Tighten the horn terminals;

Note: Please make sure that the speakers’ wires is not attached to each other, the speaker connection area is very narrow,  it is easy to cause the positive and negative speakers’ wires to contact each other, which will result in no sound output.
Method 2: Banana plugs connection illustration

1. Release the banana jacket;
2. Loosen the screw;
3. Insertion speaker wire and tighten the screw;
4. Tighten the banana jacket;
5. Insert the banana plug into the horn terminals of the speaker and amplifier.

Note: Please make sure that the speakers’ wire are not attached with each other, the speaker connection area is very narrow, it is easy to cause the positive and negative speakers’ wires to contact each other, which will result in no sound output.

Bluetooth Input
Prepare your Bluetooth device (take a phone as an example)
Step 1: Install the Bluetooth antenna.
Step 2: Switch the input mode to the “BT/USB” position, the “BT/USB” indicator shows blue light.
Step 3: Turn on the Bluetooth on your phone and connect “BT HIFI AUDIO”.
Step 4: Open the audio application, play and enjoy!

AUX Input
Prepare audio source (take a TV as an example), an RCA cable.
Step 1: Switch the input mode to the “AUX” position, the power indicator shows red light;
Step 2: Connect your TV to “Audio Input” via an RCA cable;
Step 3: Open your TV, play and enjoy!
U-disk Input
Prepare: a U-disk
Step 1: Switch the input channel to the “BT/USB” position, the “BT/USB” indicator shows blue light.
Step 2: Insert the U-disk into the “USB” port on the front panel, and BL20C will automatically recognize the music format in the U-disk.
Step 3: Short press the “PREV”, “NEXT” or “P/M” buttons on the front panel of BL20C to select or pause your songs.
Note: The capacity of the U-disk for BL20C should be under 32GB, and no more than 100MB per file.
Note: Make sure there is no Bluetooth connection, if there is, please press and hold the “P/M” button to switch to USB mode.

Troubleshooting/QA

1. What type of speakers work best with the BL20C Amplifier?
   • Fosi Audio BL20C amplifier works great with any 4-8 ohm passive speakers. But please be attention that the amplifier is for passive speakers and an active subwoofer, not for active speakers.

2. Can I connect a turntable to a BL20C amp, why is the volume is extremely low?
   • As for the turntables do not have a built-in preamp, if not connected to a phono preamp first, the volume would be below.
   • As for the turntables which have a built-in preamp, you can connect directly to the BL20C with the turntable.

3. Why does the sound is cracking or make a lot of electric noise?
   • Please make sure all the cables are completely pushed into the devices, incompletely connection will cause this cracking.
   • Please remove all the inputs then check whether cracking noise disappears or not, the cracking may be from the audio source or input cables.
   • If you are not using the original factory standard power supply, please replace the power supply before testing. Many power
   supply in the market has large interference coefficients, which will cause a lot of current sounds.

4. My Bluetooth device cannot pair with BL20C?
   • Make sure that you have selected the input channel to “BT/USB” on the front panel of the BL20C, and the “BT/USB” indicator shows blue light.
   • Make sure there is no U-disk on your device because U-disk takes priority over Bluetooth.
   • Make sure that BL20C is powered on.
   • Make sure that BL20C is not paired with other devices.
   • Make sure that the distance between your device and BL20C is not too long.
   • Make sure there are no barriers between your device and BL20C, barriers will affect the Bluetooth operation distance.
   • Please reconnect the power supply to the BL20C, and move the BL20C to another room to have a try.
   • Restart the BL20C and then try to connect again, try to use other Bluetooth devices.

5. Why Bluetooth is intermittent?
   • Please try with another Bluetooth device.
   • Make sure there is no interference from other electronic devices between the BL20C and your audio source.
   • Place your device close to the BL20C, and plug in the power adapter again.

6. How much power does it take in standby mode? Can this amp be left on all the time?
   • This is the class D amplifier, it will cost very low power when it is in standby mode. It can be connected all the time and it is safe without power consumption.

7. Sound quality is not good?
   • Make sure all the cables are fully connected.
   • Adjust the treble and bass control of the power amplifier to achieve the right tone.
   • Please try to change the sound source and cables to test.

8. Can BL20C accept signals from a Bluetooth microphone?
   • Please make sure your Bluetooth microphone must be the transmitter. Because BL20C is a Bluetooth receiver amplifier.
   • Please make sure that the microphone’s Bluetooth can be connected to the BL20C’s Bluetooth by your operation.

9. Why does the sound cut in and cut out?
   • Please try to change the sound source.
   • Lower the treble and bass of the BL20C.
   • Make sure that the positive and negative terminals of the speaker outputs do not touch each other. Some of the larger banana plugs can easily touch each other and cause a short circuit.

10. Can I bridge channel 1 and channel 2 to get 320watts?
    • No, this amplifier can’t be bridged.

11. Why does distortion occur?
    • When the output power of the BL20C exceeds the normal output power, there will be a large distortion. That means if you turn the sound up too loud, distortion may occur. Please try turning the volume down a little.

12. Why does my power indicator not light up?
    • Please check that the AC power cord is securely connected to the power supply and to an AC power outlet.
    • Please check that the AC power outlet is supplying power, make sure the power LED on the power supply will stay on.
    • Please replace another power supply and try it again. 19-35V DC power supply are suitable.
    • If you make sure the power supply is defective, please contact us for exchange.

13. How can I use BL20C to create a 2.1 Channel system?
    • You can connect two passive speakers via “SPK OUT” and one active subwoofer via “SUB OUT” to create a 2.1 Channel system.
    • Please use an RCA cable to connect your active subwoofer to the “SUB OUT” output port.

14. Can I connect Bluetooth and U-disk at the same time?
    • No, when the U-disk plugs in, the Bluetooth connection will be interrupted.
    Input priority: U-disk Input > Bluetooth Input

15. How can I connect BL20C to TV?
    • The RCA jack is the audio input on the back panel of the BL20C. It can be connected to your TV via RCA cables.

16. Why there is no voice from my speakers?
    • Please make sure the input mode you select is consistent with your input method.
    Note: If you use U-disk, please make sure the capacity of U-disk should be under 32GB, and no more than 100MB per file
    • Please check whether the cable of the power supply is connected to BL20C and whether the power indicator is on.
    • Make sure the BL20C’s indicator light is on when the power is turned on.
    • Please check that the BL20C and your source components are turned on and not set to minimum volume, if possible replace your source and test again.
    • Check that the wire connections from the audio source to each speaker in the amplifier are connected correctly.
    • Please check that the cable and your U-disk are not loose or damaged. Incomplete connection is one of the main reasons for no sound.

17. Does BL20C support aptX-HD and aptX-LL?
    • No. BL20C does not support aptX-HD and aptX-LL.

18. One channel does not work?
    • Please test whether the Bluetooth and RCA input have the same problem first.
    • If the two modes have the same problem, swap the speaker cables of the left and right channels, or change another speaker, and then test whether this channel still does not work.
    • If only RCA or Bluetooth mode does not work, change the audio source, change the RCA cable and test again, and make sure that all the cables are completely pushed into the device.

Warranty Information

• All Fosi Audio products have an 18-month limited warranty on parts and labor from the date of purchase. Please contact us if you have any problems.

About Fosi Audio

• Fosi Audio designs and builds innovative audio products with all your music in mind. Great sound, simple but elegant designs, high-quality materials, and truly useful features are what Fosi Audio is about. We sincerely hope you get as much enjoyment from our products as we’ve had to create them!

Our website: www.fosiaudio.com
Amazon store: www.amazon.com/fosiaudio
Our Youtube channel: Fosi Audio
Our Facebook page: Fosi Audio
After-sale Service and Technical Support Email: support@fosiaudio.com
customer@fosiaudioshop.com

https://h5.shengcai.net/wwei/url?url=H666G_V7w6G

Read User Manual Online (PDF format)

Read User Manual Online (PDF format)  >>

Download This Manual (PDF format)

Download this manual  >>