Wuzhi Audio ZK-502M Mini Bluetooth 5.0 Amplifier Board 50W+50W Dual Channel Stereo

The Wuzhi Audio ZK-502M is an ultra-compact, high-performance dual-channel digital power amplifier board engineered for high-fidelity custom audio systems. Delivering up to 50 Watts per channel into left and right stereo outputs, this miniature module is perfect for building standalone portable Bluetooth speakers, upgrading passive desktop monitors, or converting vintage speaker cabinets into modern wireless audio systems. Its low-profile, double-plated protective acrylic enclosure ensures rugged durability on the test bench or inside your custom speaker builds.

This module features an integrated multi-source digital audio interface that lets you switch seamlessly between diverse media platforms:

• Wireless Bluetooth 5.0: Provides low-latency, high-bandwidth wireless audio streaming from smartphones, tablets, or laptops over distances up to 15 meters.
• USB Input Interface: Connects directly to laptops, computers, or compatible single-board computers via a micro-USB cable, functioning as a plug-and-play USB DAC / external sound card.
• 3.5mm AUX Input: Features a physical analog line-in jack for connecting traditional media sources like MP3 players, CD decks, or pre-amplified instrument feeds.
• 3.5mm AUX Output: Functions as a dedicated headphone jack or a pass-through pre-amp line out to feed audio into larger, high-power secondary amplifiers.

Unlike standard miniature amplifier modules that combine power switching directly into the volume potentiometer—often resulting in line pops and accelerated wear—the ZK-502M is designed with separate controls. It features a standalone, heavy-duty latching ON/OFF toggle push-switch on the bottom left to completely disconnect the internal circuitry from your power supply. At the center sit a high-grip aluminum volume knob and flanking visual volume level graphics, providing smooth, scratch-free attenuation across the entire volume spectrum.

• Manufacturer Model: Wuzhi Audio ZK-502M
• Core Amplifier Architecture: Class-D Digital Audio IC
• Input Operating Voltage: DC 5V to 24V (Standard 5.5mm x 2.1mm DC power jack)
• Maximum Output Power: 50W + 50W (Dual-channel stereo)
• Compatible Speaker Impedance: 4 Ohm, 6 Ohm, or 8 Ohm passive speakers
• Bluetooth Revision: Bluetooth 5.0
• Audio Input Layout: Bluetooth 5.0, USB In (Micro USB sound card), 3.5mm AUX Line-In
• Audio Output Layout: 3.5mm AUX headphone jack / Left and Right terminal blocks for speakers

To achieve maximum performance without thermal throttling or audio clipping, choose an appropriate power supply matching your speaker setup:

• 12V Power Supply: Produces up to 12W+12W (8 Ohm) or 20W+20W (4 Ohm)
• 15V Power Supply: Produces up to 20W+20W (8 Ohm) or 30W+30W (4 Ohm)
• 19V Power Supply: Produces up to 30W+30W (8 Ohm) or 40W+40W (4 Ohm)
• 24V Power Supply: Produces up to 40W+40W (8 Ohm) or 50W+50W (4 Ohm)