Fosi Audio BT20A MAX Stereo Power Amplifier | 2×180W Rated | Bluetooth 6.0 | TPA3255 Hi-Fi Amplifier with 48V 5A Power Supply

Experience powerful stereo audio with the Fosi Audio BT20A MAX Stereo Power Amplifier, designed for listeners who want high output, clean sound, and flexible connectivity in a compact Hi-Fi system.

Built around the TPA3255 Class-D amplifier chip and NE5532 operational amplifier, the BT20A MAX combines efficient amplification with advanced circuit design. Its PFFB (Post-Filter Feedback) technology is designed to help reduce distortion and improve performance across different speaker loads.

The amplifier features Bluetooth 6.0 connectivity powered by the Qualcomm QCC3095 chipset, supporting multiple wireless audio codecs. Dual RCA inputs allow you to connect compatible wired audio sources, while the dedicated subwoofer output makes it convenient to build a 2.1-channel home audio setup.

An integrated cooling fan helps manage heat during demanding listening sessions. The motorized analog volume control also allows convenient volume adjustment using the included remote control.

This package includes a 48V 5A power supply/charger rated at 240W, providing a compatible power option for your amplifier, subject to confirmation of the manufacturer's input requirements.

Whether you're building a home stereo system, upgrading your existing Hi-Fi setup, or creating a custom 2.1-channel audio system, the BT20A MAX offers a versatile combination of power, connectivity, and audio control.

Main Features

1. High-Power Stereo Class-D Amplification

The BT20A MAX uses the TPA3255 Class-D amplifier chip for powerful stereo audio and efficient operation.

Rated output power: 180W per channel, manufacturer-stated
Peak output power: 300W per channel, manufacturer-stated
Stereo configuration: 2-channel
Designed for compatible passive speakers

Actual output depends on the power supply, speaker impedance, distortion level, and operating conditions. The advertised peak rating should not be interpreted as continuous RMS output.

1. PFFB Technology for Clean Audio

Post-Filter Feedback (PFFB) technology is designed to improve amplifier performance by providing feedback after the output filter.

Manufacturer-stated specifications include:

THD: ≤0.003%
Signal-to-noise ratio: ≥112dB

Actual measurements may vary depending on output power, frequency, speaker load, and testing conditions.

1. Bluetooth 6.0 with Qualcomm QCC3095

Enjoy wireless music playback from compatible smartphones, tablets, computers, and other Bluetooth-enabled devices.

Supported codecs listed in the supplied specifications:

LDAC
aptX Lossless
aptX HD
aptX Adaptive
aptX
SBC
AAC

The listed maximum Bluetooth audio specification is PCM 24-bit/96kHz.

Note: Available codecs and playback quality depend on the source device, operating system, and Bluetooth configuration.

1. CS4398 Digital-to-Analog Converter

The BT20A MAX features a CS4398 DAC for compatible digital audio processing.

The supplied specifications list:

Dynamic range: up to 120dB
THD+N: as low as −107dB
High-resolution audio support as specified by the manufacturer

These figures refer to stated DAC specifications and may not represent the measured performance of the complete amplifier under every operating condition.

1. Dual RCA Inputs

Two RCA inputs provide flexibility when connecting compatible external audio sources, including:

DACs
Preamplifiers
Audio streamers with analog outputs
Computers with analog audio outputs
Other line-level audio devices

1. Dedicated Subwoofer Output

The dedicated subwoofer output supports integration into a compatible 2.1-channel audio system.

A typical setup includes left and right passive speakers plus a compatible active subwoofer.

Check the manufacturer's connection instructions before use. Do not assume the subwoofer output directly powers a passive subwoofer.

1. Bass and Treble Controls

Choose between the available listening modes:

Bypass Mode

Bypasses the adjustable tone-control function for a more direct signal path.

Tone Mode

Allows bass and treble adjustment to suit your speakers, music, and room.

1. Motorized Analog Volume Control and Remote

The motorized analog potentiometer allows convenient volume adjustment using the amplifier's control or the included remote control.

1. Integrated Cooling Fan

The built-in cooling fan helps dissipate heat during demanding operation.

The fan may increase its speed during prolonged high-power use. This is normal operation. Keep ventilation openings unobstructed.

1. 12V Trigger Input

The 12V trigger input allows power operation to be synchronized with compatible audio equipment. Check the connection requirements of both devices before connecting them.

1. High-Pass Filter Adjustment

The supplied specifications identify an HPF adjustment feature. A high-pass filter reduces selected low-frequency content reaching the connected speakers, depending on the filter settings and implementation.

Consult the manufacturer's instructions for the available adjustment range and operating procedure.

1. Included 48V 5A Power Supply/Charger

This package includes a 48V 5A power supply/charger rated at 240W.

Output voltage: 48V DC
Output current: 5A
Rated output power: 240W

Important: Confirm that the power supply's voltage, polarity, connector, current capacity, and other electrical requirements match the amplifier manufacturer's specifications before connecting it. A 240W power supply does not guarantee that the amplifier will deliver its advertised peak output under all conditions.

Applications
Home Hi-Fi stereo systems
High-quality music listening
Bookshelf and floorstanding passive speakers
Custom 2.1-channel audio systems
DAC-based stereo systems
Desktop and living-room audio
Bluetooth music streaming
Home audio upgrades
Technical Specifications
Specification Details
Brand Fosi Audio
Model BT20A MAX
Product Type Stereo Power Amplifier
Amplifier Class Class-D
Amplifier Chip Texas Instruments TPA3255
Operational Amplifier NE5532
Audio Channels 2 Channels
Rated Output Power 180W × 2, manufacturer-stated
Peak Output Power 300W × 2, manufacturer-stated
Feedback Technology PFFB
Bluetooth Chipset Qualcomm QCC3095
Bluetooth Version 6.0
Bluetooth Codecs LDAC, aptX Lossless, aptX HD, aptX Adaptive, aptX, SBC, AAC
Listed Maximum Bluetooth Audio PCM 24-bit/96kHz
DAC Chip CS4398
THD ≤0.003%, stated specification
Signal-to-Noise Ratio ≥112dB, stated specification
Analog Inputs Dual RCA
Subwoofer Output Yes
Tone Controls Bass and Treble
Bypass Mode Supported
Volume Control Motorized Analog Potentiometer
Remote Control Included
Cooling Integrated Cooling Fan
Trigger Connection 12V Trigger Input
HPF Adjustment Supported, according to supplied description
Included Power Supply 48V 5A
Power Supply Rated Output 240W
Power Supply Output Voltage 48V DC
Power Supply Output Current 5A

Note: Confirm the amplifier's required power-supply specifications, supported speaker impedance, dimensions, and weight from the manufacturer's documentation before installation.

Key Benefits
Powerful stereo amplification in a compact unit
PFFB technology designed to improve output performance
Bluetooth 6.0 with multiple supported audio codecs
CS4398 DAC
Dual RCA inputs for wired audio sources
Dedicated subwoofer output for compatible 2.1-channel setups
Remote-controlled motorized volume adjustment
Adjustable bass and treble
Integrated fan-assisted cooling
12V trigger input
48V 5A (240W) power supply/charger included
Package Includes
1 × Fosi Audio BT20A MAX Stereo Power Amplifier
1 × Remote Control
1 × 48V 5A (240W) Power Supply/Charger

Confirm the exact package contents and power-supply compatibility before purchase.

Important Notes
The BT20A MAX is a stereo power amplifier for compatible passive speakers.
The advertised 300W-per-channel peak rating is not the same as continuous RMS power.
Actual output depends on the power supply, speaker impedance, cooling, and operating conditions.
Bluetooth codec support depends on the connected source device.
Use the subwoofer output according to the manufacturer's instructions.
Ensure sufficient ventilation during high-power operation.
Confirm power-supply compatibility and supported speaker impedance before connecting the equipment.