Fosi Audio BT20A Pro Bluetooth 5.0 Amplifier 300W x2 TPA3255 2 Channel Mini Class D Integrated Home Audio Outdoor Stereo Amp Receiver for Speakers Supports 24-48V with Bass Treble Control Item Description 300 Watts x 2 Power Output: The TI TPA3255 chip amplifier has a feedback design and high-speed gate driver error connection for efficient and quality audio performance, with a low idle loss of <2.5W High-Efficiency: The chip amplifier has replaceable Op-Amps for a custom approach when compared to the BT20A amplifier. Further, you can swap the 2 plug-in NE5532 Op-Amps for LME49720HA, MUSES02, OPA2604AP, OPA2134PA, LM4562, or NJM4556AD Op-Amps to achieve distinct sound qualities. It boasts an SNR≥108dB and THD≤0.005% Bluetooth 5.0 Connectivity: The Bluetooth pair can be removed by pressing and holding the volume control for 5 seconds, and it also has a memory function for easy pairing and an alert tone for convenience Custom Sound with Bass and Treble Controls: The BT20A Pro home audio amplifier has a sound control design so that you can experience sound without effects by setting treble and bass effects to the middle point Package Contents: The package contains a BT20A Pro power amplifier, a Bluetooth antenna, a 32V/5A power adapter, an AC cord, and a user manual *Input: Bluetooth + RCA; Output: Passive Speakers + Pre-out*THD: ≤ 0.005%; SNR: ≥108dB; Frequency Response rRange: 20Hz-20kHz(±1.2dB)*Bluetooth Distance: ≥15m; Bluetooth Transmission Format: SBC/AAC*Bluetooth 5.0 Connectivity Allowing you to connect your devices such as mobile phones and tablets from a greater distance.*Unique Design for Sound Control Experience the authentic sound without any added effects by adjusting them to their middle points.*Full-range Pre-Out Output Easily connect to a powered subwoofer, speaker, or another amplifier for versatile audio options.*Texas Instrument TPA3255 Chip Has a unique smart algorithm that optimizes the output stage for max efficiency and min distortion.*Achieve a Distinct and Exceptional Sound Quality The two plug-in NE5532 Op-Amps can be replaced by LME49720HA/MUSES02/OPA2134PA Op-Amps, etc.*High Precision and Stability Inductance Values Low DC resistance and excellent frequency characteristics which improve performance*Low DC resistance and excellent frequency characteristics which improve performance Allowing you to connect your devices such as mobile phones and tablets from a greater distance.Experience the authentic sound without any added effects by adjusting them to their middle points.Easily connect to a powered subwoofer, speaker, or another amplifier for versatile audio options.Has a unique smart algorithm that optimizes the output stage for max efficiency and min distortion.The two plug-in NE5532 Op-Amps can be replaced by LME49720HA/MUSES02/OPA2134PA Op-Amps, etc.1. Ensure that all wiring is correct. 2. There is no signal interference nearby.4. If there are multiple input modes, check whether other input modes work properly.5. Try using different Bluetooth devices, speaker wires, and speakers. 6. Change the environment.7. If there is a Bluetooth antenna included, ensure that it is connected correctly and try using a different antenna.2. Adjust the treble and bass control of the power amplifier to achieve the right tone.3. Please try to change the sound source and cables to test. Payment We accept all forms of payment through eBay Shipping Items ship free the next business day Return Free 30 Day Returns