Product Specifications

Fosi Audio BT30D is a HiFi Bluetooth 5.0 power amplifier that features SUB Volume/Frequency control, Bass/ Treble control. The BT30D supports Bluetooth or RCA input, suitable for most home passive speakers, passive/powered subwoofer.

The BT30D adopts 2 PCS Texas Instruments (TI) TPA3116D2 high-performance chips to output 200W stably, low distortion to show ultra-high- definition sound quality. The perfect solution to meet all your audio needs! Let’s join the audiophile’s music journey with Fosi Audio BT30D!

Audio Input :

Bluetooth , RCA

Output interfaces :

Sub pre-out, Speaker’s output, Subwoofer output

Output :

Active(powered) subwoofer, passive subwoofer,

passive speakers.

Power amplifier chip :


Power Adapter :


DC Input Range :



≥ 0.04°.



Frequency Range :

20Hz – 20kHz (±1 dB)

Input Sensitivity :


Terminating Impedance :

≤ 2-8 Ohm

MAX Power Output :

50W x 2+100W

Bluetooth Transmission

Distance :

Up to 50 Ft

Power output :


Product Overview & Control Functions

Package Content

BT30D Bluetooth Amplifier x1

Bluetooth Antenna x1

User Manual x1

Power Adapter x1

Quick Setup

How to Use?

Step 1:

① Connect the power adapter to the socket and the BT30D. Please make sure the blue LED light on the power adapter stays on.

② You can use the banana plugs or bare wires to connect the passive subwoofer and passive speakers to the BT30D.

③ You can use the RCA cable to connect the powered subwoofer to the BT30D.

④ Then turn on the power switch on the front panel of the BT30D.

Step 2:

① RCA line input: Use an RCA cable to connect the BT30D and your device. The input mode indicator light will turn red after a successful connection.

② Bluetooth input: Turn on the Bluetooth on your device, then select “Fosi Audio BT30D” for pairing, the input mode indicator light will turn blue after a successful connection. Once Bluetooth is connected, the RCA input will be interrupted. If you want to use the RCA input again, just disconnect the Bluetooth.

Step 3:

Adjust the volume control, SUB volume/Frequency control, Bass/Treble control, then enjoy it!


2. Get noise when playing music?

  • Try to use other Bluetooth devices. Weak or unstable Bluetooth signal will cause this problem, try to close your device to the BT30D.
  • Try another RCA cable and make sure the audio cable is connected correctly.
  • Please unplug the RCA cable from the amplifier, and then turn it on to have a try.
  • Please change the audio cable and audio source to have a try.
  • Did you set the “treble” volume to the top† please volume down the “Treble” volume.
  • The gain of BT30D is larger than other model, you can volume down the “Treble” sound. Some speakers are very sensitive so that the white noise will be obvious, it’s normal that BT30D has some noise when you turn up the “Treble” volume.
  • Make sure that all the cables are completely pushed into the device, incompletely connection will cause this issue.
  • Please keep this device away from other electronic devices.

2. All cables are connected, but there is no audio output?

  • Please check the indicator light on the front panel of the amplifier and the power supply are on.
  • If the indicator light is on, please check if the volume knob is at the minimum state, if it is, please turn up the volume.
  • Make sure that BT30D is in the play mode you want.

Note: Bluetooth input mode (The input mode indicator light will turn blue.) RCA input mode (The input mode indicator light will turn red.) Once Bluetooth is connected, the RCA input will be interrupted.

  • Please check if the audio source is paused.
  • Please try to change the sound source, cables and speakers/subwoofer.
  • Restart the BT30D and your device, then try to connect again.

Note: Make sure that all the cables are completely pushed into the device.

3. My Bluetooth device can’t pair with BT3OD?

  • Make sure that BT30D is powered on and the LED light on the power adapter is blue.
  • Make sure that BT30D is not paired with other devices.
  • Make sure that the distance between your device and BT30D is not too long, close your device to BT30D to have a try.
  • Make sure there are no obstacles between your device and BT30D, obstacles will affect the Bluetooth operation distance.
  • Please try to change another Bluetooth audio source to test.
  • Please replug the power supply, move the amplifier to another room and test it again.
  • Restart the BT30D and then try to connect again, try to use another brand of mobile phone.

4. 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.

5. Does the BT30D support Bluetooth aptX and Low  Latency?

  • No. BT30D does not support Dolby, aptX, aptX HD and aptX Low Latency.

6. Can this amp be left on all the time?

  • It can be connected all the time and it is safe without power consumption.

7. Should I unplug the power cordt

  • If the item will not be used for a long time, please unplug the power plug to prevent the item from being burnt due to lightning strike.

8. Do I have to connect all the outputs of BT30D? Can I only connect one speaker? Or just use it as a subwoofer preamp?

  • Yes, you can do it. You don’t need to connect all the outputs.
  1. What does the SUB FREQ knob dot Does it only adjust the frequency output by the passive subwoofer?
  • SUB FREQ is to adjust the output frequency of passive subwoofer and pre-out, the adjustment range

is 0-300Hz.

9. Can the BT30D be used as a 2.0 channel power amplifier? Can it be used without connecting the subwoofer?

– Yes.

10. Is the Bass adjustment effective for the passive subwoofer of the BT30Dt

  • Yes, it works.
  • Why Bluetooth is intermittentt
  • Use another Bluetooth device to have a try.
  • Ensure that there is no interference from other electronic equipment between the BT30D and the audio source.
  • Put your device close to the BT30D.
  • Replug the power adapter.
  • What speakers are suitable for the BT30D?
  • BT30D is suitable for most home audio-visual systems, it can drive 20-200watt, 2-8ohm speakers.

11. Why the sound cut in and cut out

  • Try to reduce the sound of the sound source.
  • Try to change the audio source to test.
  • Reduce the volume of the treble and bass knob on the BT30D.
  • Ensure that the positive and negative poles of the speaker output do not touch together. Some relatively large banana plugs are easy to touch together and cause a short circuit.

12. Can I take the BT3OD to other countries?

  • Yes, the wide voltage AC 110-240V for power input can be used in any country. You only need to match the power cord adapter of the corresponding country.

Comparison Section

  • 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.