Fosi Audio BT20A Bluetooth Stereo Amplifier, 2 Channel Home Audio Component Amplifiers for Passive Speakers, Mini Class D Amp Receiver 200W for Indoor/Outdoor/Garage/Ceiling/Bookshelf Speaker

QCCAN 4pcs TDA2822M Audio Amplifier Board 2.0 Channel Stereo AMP Mini AUX Audio Amplifier Module DC1.8-12V

2 in 4 Out Audio Digital Signal Processor DSP Kernal Board - ADAU1701 Supports Adjusting Gain EQ Crossover and Time Alignment

Bogen 250 Watt Amplifier

Audtek Electronics Audtek VC-100R Impedance Matching Rotary Speaker Volume Control 100W

Rodipu DIY 12 Level Dual Audio Spectrum Display, Durability VU Meter Amplifier Board, DIY Electronic Kits for Musicians and(Music Spectrum Level Indicator)

6J1 Valve Preamp Buffer DIY Kits, 6J1 Electronic Tube Preamp Amplifier Board Headphone Amp Parts Kit

ZK-3002T Stereo Receiver 2.0 Channel Bluetooth Audio Board 300W+300W TPA3255 with Treble and Bass Control Mini Home Audio System for Speakers Electronic Component Amplifiers

ZK-MT21 2.1 Channel Bluetooth Subwoofer Amplifier Board Module, 50Wx2+100W DC12-24V, Bluetooth and AUX Input, with Treble and Bass Control, for DIY Bluetooth Speaker

eMagTech 10PCS Dual Low-Noise TL072CP TL072 DIP-8 Operational Amplifiers, Dual Low-Noise JFET Input OP-AMP IC Chips for DIY Circuit Components