Fosi Audio BT20A Channel Bluetooth 5.0 Power Amplifier User Manual

T20A User’s Manual

Before using this product, Please be sure to read carefully this instruction manual and keep it safe for further reference

Introduction

Welcome to the Fosi Audio family and congratulations on your purchase of the Fosi Audio products.
The Fosi Audio team is dedicated to bringing you the highest-quality listening experience and the Fosi Audio converters were designed with the same attention to detail and operational simplicity as all other Fosi Audio products. Our goal is to get you to your music as simply as possible without all the “gadget tinkering ” many other products require. As with our past efforts, we thank our customers, distributors, and resellers for the inspiration to create another great product.

Contact us

Our website: www.fosiaudio.com
Amazon store: www.amazon.com/fosiaudio
Our Youtube channel: Fosi Audio
Our Facebook page: Fosi Audio
Email address: [email protected]
[email protected]

Package Contents

• Fosi Audio BT20A Amplifier
• AC Power Cord
• 24V Power Supply
• Instruction Manual

BT20A Product Specifications

• Bluetooth 5.0 , 2.0 CH
• Bluetooth Pair PIN Code: 0000 or 1234
• SNR: ≥ 98dB
• Input Sensitivity: ≤ 280mV
• THD: ≤ 0.5%
• Output Power: 100W + 100W
• Power Supply: 24V 4.5A
• With Bass and Treble Volume Control
• Terminating Impedance: 2Ohm – 8Ohm
• Bluetooth Transmission Distance: 28ft
• Frequency Range: 20Hz – 20kHz (±1 dB)
• Input Mode: Bluetooth and Analog
• Product Size: 130 x 100 x 35 mm
• Product Weight: 700g

Cleaning

Your home audio amplifier components are not water-resistant, so it’s important that they should be kept free of moisture. You should clean only with a dry cloth or tissue and no liquid cleaners or solvents should be used.

Product Overview

1. Power Switch
2. Treble Control
3. Bass Switch
4. Volume Control
5.  Power Indicator

1. RCA Input
2.  Speaker Output
3. DC 24V Input
4.  Bluetooth Antenna

Quick Setup

Setup and Operation

How to use the BT20A amplifier?
Step 1 – Connecting the Speaker Wire
BT20A accept bare wire, banana plugs, spade lugs, or pin terminators.
Please turn off the amplifier before connecting it to the speakers.

Preparing the Speaker Wire

1. Separate the last 3” of each speaker wire conductor.
2. Strip ½” of insulation from the end of each wire.
3. Twist the exposed copper strands with your fingers 3 or 4 times so the strands stay together.

NOTE: As you make your connections, be sure to connect the positive (+) terminals on your amplifier to the positive (+) terminals on your speakers.Even if your wire does not have (+) or (-) markings, most 2- conductor speaker wire has printing on one side to help you differentiate between the wire pairs. The 4 pictures show how to make banana connections as follows:

Using Bare Wire

1. Use your thumb and finger to unscrew the binding post connectors on the back of each speaker.
2.  Insert each speaker wire into the holes on the side of the binding post connectors, observing proper polarity.
3.  Retighten the binding posts with your fingers.
4.  The stripped portion of the wire should be secured firmly in each connector.
5. Make sure that none of the speaker wire strands have come in contact with an adjoining terminal.
6. Repeat steps 1 and 5 to connect speaker wires to the amplifier.

Step 2 – Connecting the Power Supply
Be sure that the volume/power switch on the front panel is in the OFF position before connecting the power supply.
Connect the cable with the round end from the power supply to the rear panel power connector. Connect the AC power cable from the power supply to a power outlet and verify that the indicator light on the power supply is illuminated. We recommend using a high-quality surge suppressor and/or AC line later on all electronics equipment.
Step 3 – Connecting Audio Sources
Using the appropriate audio cable (RCA cable), connect your audio source (computer, iPod, etc.) to amplifier audio inputs.
If you want to connect the amplifier to the audio source via Bluetooth, you can pair them when the amplifier is turned on. Fosi Audio Bluetooth amplifiers can connect to only one device at one time, The Bluetooth name is Fosi Audio, when the Bluetooth is paired, the LED light on the front panel will turn to blue from red.
NOTE: Some Fosi Audio Bluetooth amplifier have the ” BT ” and ” AUX ” selector(BT20C, BT30A..), you can choose the input way when you connect the audio source. Some amps don’t have the selectors ( BT1OA, BT20A), so once the Bluetooth connects, the RCA input will interrupt, so if you want to connects the amplifier with RCA input, you need interrupt the Bluetooth connects from your Bluetooth device.
Step 4 – Operation
Turn on the BT20A volume/power knob and set the volume control to an initial set of about 12 o’clock. Turn on your audio input source and adjust the volume to your desired listening level.

Troubleshooting Tips

1. Power Supply Indicator is not Illuminated.
   1). Check to see that the AC power cord is securely connected to the power supply and to an AC power outlet.
   2). Check that the AC power outlet is supplying power, make sure the power LED on the power supply will stay on.
   3). If you make sure the power supply is defective, please contact us for exchange.

2. If the Power Supply Light is on But You Are Experiencing an AudioRelated Issue, Try These Tips.
   1). Verify that the volume/power control on the front panel is not turned all the way down or powered off (we recommend setting the volume to at least the 12 o’clock position).
   2). Check that the volume level of your audio source component or device is not set to minimum volume or powered off.
   3). Check speaker wire connections from the amp to the speakers by removing the speaker wire from each speaker and then reconnecting. Also, check the speaker wire polarity by verifying that the wires are going to the same terminals on both speakers.
   4). Check that the cables from your audio sources to the amplifier are properly connected. Confirm this by unplugging the audio cables and then reconnecting.
   5). Try decreasing the volume of the input audio source and increase the volume of the amp.
   6). Try using different audio input sources and/or devices to see if the problem follows.
   7). Try swapping your left and right speaker to see if the issue remains on the same channel or if it follows the speaker.
   8). If you are using a computer connected to the amplifier, make sure the volume is up on your media player, internet radio, master control, device volume, etc. and that the balance control as centered.
   9). If you are using a wireless adapter, preamp, or an external DAC with your amplifier, remove these (temporarily) and connect the audio source directly to the amplifier then to speakers.
   10). If your input source has this own EQ, please make sure the low end is at a moderate level, as having too much bass in your signal can obviously cause some unwanted distortion.
   11). Move your amplifier and speakers to a different location to see if something is causing interference in the current setup. Something as simple as a wireless internet router, cordless or mobile phone, or halogen lamp nearby can cause interference.
   12). If you are using the bluetooth connection, make sure the selector of the amplifier is selected the input way(BT20C, BT30A…), and if you are using BT10A, BT20A or BT-01 amplifier, please make sure whether the amplifier paired with your bluetooth device or not, once the amp paired with your device, the RCA output will interrupt, so please disconnect the Bluetooth to try again. (Turn off the Bluetooth or cancel pair from your Bluetooth device)

3. No Sound.
   1). Recheck speaker wire connections from the amplifier to each speaker.
   2). Verify that the amplifier and your source components are turned on.
   3). Check that the AC wall outlet is on and working.
   4). Check that the cable from the power supply is connected to the amp and the power supply indicator is on.
   5). Check that the volume/power knob on the front panel is turned on and not set to the minimum volume.
   6). Check that your audio source(iPad, computer, etc.) are turned on and not set to the minimum volume, please change the audio source if you can.
   7). Check that the cables from your audio sources are working and are properly connected.
   8). Please sure the “Power” LED on the amp is on when you switch on.
   9). Please ensure the Bluetooth is not paired, if Bluetooth connects, playback from the physical input(RCA or AUX input) is interrupted. If you want to connect this amplifier with the audio cable(physical input), you need to interrupt the Bluetooth first. (turn off Bluetooth from your Bluetooth device). And if you got the newer model(BT20C, BT30A…), make sure the selector of the amplifier is selected the correct input way.

4. Sound Through One Speaker Only.
   1). Recheck all speaker wire connections on the speakers and the amplifier.
   2). Check that the cables from your audio sources to the amplifier are properly connected.
   3). Please swap the RCA input, right and left channel, if the opposite channel can’t work, the issue may from your audio source or RCA cable.
   If that channel still can’t work, the issue may from your speakers or this amplifier. Please contact us if this amp has this issue.
   4). Please exchange the speakers’ wire from the amplifier speakers’ output, if the issue remains, the issue may from the speaker or the speakers’ wire, if the issue follows, the issue may from the amplifier
   5). If you are using a computer connected to the amplifier, make sure the volume is up on your media player, internet radio, master control, device volume, etc. and that the balance control as centered.

5. Lack of Bass or Poor Imaging.
   1). Check the polarity of the speaker wires on the amplifier and both speakers.
   2). Check the EQ or sound settings on your audio source.
   3). Make sure the bass control on the amplifier has set up.

6. Sound Distorted.
   1). Decrease the volume of the input audio source and increase the volume of the amplifier.
   2). Please make sure your speakers are passive speakers, not active speakers.
   3). Please unplug the RCA input, connect this amp to your speakers, then connect it to power supply, switch on and volume up, to hear whether noise or hum remain, if yes, the issue may from the amplifier or your speakers, if not, the issue may from your RCA cable or audio source, please change the audio source and audio cable to try again.
   4). Please make sure all the cable completely pushed into the device, incompletely connections will create distorted.

5. Please make sure the BT20A have enough power to drive your speakers, check the specs of your speakers, and if you need more power, you can use a more powerful power supply, such as 24V 8A, 24V 10A.

7. Low Volume.
   1). Recheck the volume on your audio source and this amplifier is turnedup and not set to minimum volume.
   2). Please make sure your audio source needs a pre-amp or not.
   3). If you are using the turntable, please make sure that if your turntableneeds an phono preamp or not, some turntable built-in phono preamp, some are not.

8. Bluetooth Can’t Work.
   A: 1). Please unplug the power supply into the AC outlet, then re-plug it again to try again.
   2). Please change the Bluetooth device to try again.
   3). Please make sure that the amplifier is not paired with your other
   Bluetooth device, once the amplifier paired with Bluetooth, the power LED light on the amplifier will turn to blue, and other bluetooth devices will not discover it.
   4). Please move your Bluetooth device close to amplifier.
   5). Please make sure the speakers and the speakers’ wire are work.

9.  Hum Noise
   Adding a new component such as your BT20A amplifier can bring out humor buzz that may not have existed before. Your first assumption may be that something is wrong with the component but this is generally caused by a “ground-loop” in your system. Consider these tips for possible solutions:

• First, try moving all components to the same electrical circuit or AC outlet.
• If the hum or buzz is still present, power off all gear and remove the mini-jack and/or RCA audio cables to and from the BT20A amplifier.
• Turn the BT20A back on and check for hum. If the noise is still audible try plugging the power supply power cable into a different AC outlet.
• If the hum goes away while the audio cables are still disconnected, the noise is likely coming from another component in your system. Connect each component back one at a time and the one that causes the system to hum is likely the culprit.
• A common ground-loop source is from cable TV or satellite cables. If the hum or buzz persists after trying the previous tips, disconnect the audio cable from your cable box, TV, or DVR and if the hum goes away the cable is the cause. In this case, you can get a ground-loop isolator from your local electronics store. These are inexpensive and easy to connect inline with your video cable.
•  Sometimes something as simple as a portable heater or dehumidier will add noise into your wall wiring that could be picked up by your audio gear. A dimmer switch on a halogen lamp, a wireless internet router, or wireless phone near the amplifier, for example, could also all be possible culprits.
  The best overall solutions are to use an AC line liter, plug the unit into a different AC circuit, or in the case of noise introduced by a wireless router, for example, move it further away from your audio gear.

FQA

Q: What Type of Speakers Work Best with Fosi Audio Amplifier?

A: Fosi Audio Amplifiers work great with any 2, 4, 6 or 8-ohm passive spakers. But Please know that the amplifier is for passive speakers, not for powered speakers and subwoofers.

Q: Can I Connet a Turntable to My Amp,Why is the Volume is Extremely Low?

A: Some Turntable may not have a built-in preamp and you would need to add an external phono preamp to bring the instrument-levesignal of the turntable to line-level. Some turntables may have a built-in preamp but have a switch on the back for either “line” or “phono”, such as the Music Hall USB-1 or the Audio Technica ATLP120, the switch would need to be selected to “ line” in order to work directly with the speakers.

Q: Can I Connect a Subwoofer to the Fosi Audio Amps?

A: If you bought subwoofer amps from Fosi Audio or 2.1 channel amplifier(the amp that with sub output), you can connect to a subwoofer, but if you got the 2.0 channel amp, you can't connect to the subwoofer.

Q: Can I Take My Amp to Another Country with a Different Voltage?

A: Fosi Audio amps come with a power supply that accepts AC110V240V, it will automatically convert to different voltage when plugged in. The power cable is also detachable which makes it convenient to replace the AC plug with a different type if you don't want to use an adapter plug.

Q: Can I Leave the Fosi Audio Amps Power on all the Time? Does it safe?

A: Sure, the Fosi Audio amps are class d amplifiers, will cost very low power when nothing playing through it, and it's safe and you can leave it on all the time.

Q: Can I exchange the power supply come with the amplifier and to get more power?

A: The BT20A come with 24V 4.5A power supply, it's enough for most bookshelf speakers, but if you want to get more power, you can exchange the power supply, the voltage range is DC12-24V, you can use 24V 8A, or 24V 10A power supply.

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 creating them!

Our Email:
[email protected]
www.fosiaudio.com

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.

Note: After-sale service email [email protected]

What Is Covered ？
All defective parts or faulty workmanship.
What Is Not Covered ？
The warranty doesn’t cover damage caused by accident, misuse, abuse, neglect, excessive moisture, lightning, power surges, other acts of nature, unauthorized product modification or repaires, or failure to follow the instructions outlined in this guide.
What We Will Do ？
We will repair or replace any defective parts, at our option, within a reasonable amount of time and free of charge any time during the warranty period.
What We Ask From You ？
You will be responsible for shipping charges to Fosi Audio or to an authorized dealer. We recommend and you keep the original shipping materials to prevent shipping damage if service is need. Fosi Audio cannot be responsible for any damages incurred during shipping due to poor packing, so please pack well and make sure to insure your shipment.

Comparison

References

• Fosi Audio
• Fosi Audio Redefining HiFi with Unmatched Value

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