You can DIY a for Bluetooth speaker, just need a battery(this product doesn't include battery), two speakers, and a case then you will get a nice for Bluetooth speaker. 2 x Power Amplifier Board. Output 5W + 5W dual‑channel stereo, support USB sound card, no driver, just plug and play.
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Gooermi D400 1U Digital Amplifier 2/4 Channel 1200W Power Amplifier Stereo Sound System Pro Audio Class D Amplifier For Stage
Aliexpress UK
PAM8403 mini type D digital power amplifier can be easily put in small space of many digital products, high amplification efficiency. Quantity: 5pcs. Type D power amplifier has very high amplification efficiency, sound quality will not be effected by temperature rise, no need of heat sink.
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SMSL AS400 Hi-Res DAC Power Amplifier Headphone AMP Support Bluetooth USB Optical Coaxial MM Vinyl Phono Amplifier Audio Decoder
Aliexpress UK
Quantity: 5pcs. This audio power amplifier uses LM386 chip. 5 Amplifier Modules. The main pin of chip can be input audio signal directly. If you are satisfied with our service, pls.
eBay
AK380/AK35/AK370/280/AK270/AK170 800W 12V Home Car Hifi Power Amplifiers Stereo BASS Audio Speaker Class D Car Home Sound Amp
Aliexpress UK
Output power: up to 4x80W stereo (18V/4 ohms), can be connected to 2/4/6/8 ohms speakers. DC12-18V 4 x 80W TDA7850 4-channel ACC Car AB Class Amplifier Module. Product category: AB class 4-channel amplifier.
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5Pcs Gold Plated Glass AGU Fuse Fuses Pack Car Audio Amp Amplifier 10A 15A 20A 25A 30A 40A 50A 60A 70A 80A 100A Car Fuse
Aliexpress UK
Introducing the XY-SP5W 5128 Digital Amplifier Board Class D 5W Mono Audio Amplifier Module, a high-quality audio amplifier module perfect for enhancing your sound system. Whether you're a music lover or a professional audio engineer, the XY-SP5W 5128 Digital Amplifier Board Class D 5W Mono Audio Amplifier Module is a must-have for anyone looking to take their sound system to the next level.
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Nobsound Latest Mini 100W Subwoofer / Full Frequency Power Amplifier Mono Channel Audio TPA3116D2 Amp
Aliexpress UK
Are you want to listen to the lossless music?. It adopts TDA7850 high quality chip and BA3121 denoiser for clear sound of music. With BA3121 noise isolation and noise-canceling. TDA7850 is a high-quality Hi-Fi car audio amplifier IC, sound quality is excellent!
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2/3/4 Way Mini ANL Fuse Holder, Copper 0/2/4 Gauge to 4/6/8 Gauge 60 Amp Fuse Distribution Block for Car Audio Stereo Amplifier
Aliexpress UK
Audio Output: Mono 30W. 2PCS Audio amplifier board. Audio input: Bluetooth + AUX + U disk + USB sound card. Model: ZK-301B.
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GHAMP 6Z4+6N3 Tube Preamplifier HiFi Valve Amplifier Preamp Borad For McIntosh C2200 Circuit Design Home Audio Amp 1PC
Aliexpress UK
Better Sound: With this audio amplifier board, you can enjoy better sound quality with low noise as well as low distortion. Item Type: Audio Amplifier Board. 1 x Audio Amplifier Board. Output Power: 5W.
eBay
MX400 Audio Mixer Headphone Amplifier Ultra Compact Sound Low Noise With Power Adapter 4 Channel DJ Karaoke Headphone Amplifier
Aliexpress UK