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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CX31993 HiFi USB Type C To 3.5mm Headphone Amplifier DAC Audio Decoder IEM AMP Mobile Phone Adapter Type-C Converter 32b/384kHz
Aliexpress UK
Item Type: Power Amplifier Module. 1 x Power Amplifier Module. Bluetooth Version: 5.0. Number of Channels: Dual channel (stereo). Wide range of applications and is suitable for operation by college students, engineers and technicians.
eBay
HIFI Digital To Analog Audio Converter Decoder 32-192KHz DAC Amp 3.5mm AUX 2RCA Amplifier Audio Toslink Optical Coaxial Output
Aliexpress UK
High Output Power (100W 2) ‑ Mono power up to 100W. High Output Power (100W 2) - Mono power up to 100W. Output power: 100W 2. amplifier board ‑ Adopts TDA7498 chip, ensures high‑quality sound.
eBay
YYTCG HIFI OFC Speaker Cable RCA to 2 Banana Plug for AMP Amplifier Speaker Soundbox Gold Plating Audio Cable 1m 2m 3m
Aliexpress UK
2 x Amplifier boards. Sound & Vision. Output power: 100W. We will be happy to resolve any issues you may have in a cordial and friendly manner. All products are quality checked. Product size: 75 63 26mm.
eBay
TRN TE DAC AMP Adapter Type-C To 3.5mm Audio Cable chip Earphone Amplifier PCM 96kHz
Aliexpress UK
Model: PAM8403. Amplifier info Excellent noise suppression - in the absence input signal, speaker output is quiet. Module can directly drive 4Ω, 8Ω small speakers. Two-channel stereo, full of energy, good sound quality.
eBay
Type C to 3.5mm HiFi DAC Earphone Amplifier USB C Audio Decoder AMP Adapter CB1200AU Chip Sound Card Digital Decoder For Android
Aliexpress UK
1PCS LM386 Super MINI Amplifier Board Module 3V-12V DIY Kit Perfect for Raspberry Pi. 10UF Capacitance x1. 100UF Capacitor x1. 1000UF capacitor x1. 10K variable resistor x1. 1K resistor x1. 3.5 Audio Block x1.
eBay
6.35 To 3.5 Audio Extension Cable 1/4 TRS Male To Dual 1/8 Female Y-Splitter Cable for Amplifier Guitar Amp Keyboard Piano Mixer
Aliexpress UK
High Output Power (100W 2) ‑ Mono power up to 100W. High Output Power (100W 2) - Mono power up to 100W. Output power: 100W 2. amplifier board ‑ Adopts TDA7498 chip, ensures high‑quality sound.
eBay
Type C to 3.5mm HiFi DAC Earphone Amplifier CX31993 Audio Decoder IEM AMP Smartphone Adapter for Android iPhone15 Samsung
Aliexpress UK
Model: TPA3116D2. Item Type: Digital Amplifier Board. 4 x Digital Amplifier Board. Number of Channels: 2 Channels. Power Efficiency: > 90%. Output Power: 2 x 80W. 4 x Knob Cover.
eBay
CX31993 MAX97220 Dual Chip Type C to 3.5mm Headphone Amplifier DAC HiFi Audio Decoder IEM AMP Smartphone Adapter for Android
Aliexpress UK