ZK-502A 2.0 Bluetooth 5.0 Amplifier Board 50W+50W - APP Control

In this review of the ZK-502A 2.0 Bluetooth 5.0 Amplifier Board the bottom line is clear: this board is for DIY speaker builders and hobbyists who want surprisingly high output and flexible inputs in a compact package. The reviewer found the device delivers strong, clean sound for its price and offers convenient controls via Bluetooth and a dedicated Android app, making it a practical choice for custom home audio projects where app-based naming and password control matter.

Key Features

• Dual 50W Output: Delivers up to 50W per channel peak power, providing substantial volume and headroom for small to medium speakers.
• Bluetooth 5.0: Modern wireless input with stable pairing for phone or tablet audio sources, simplifying playback without extra wiring.
• Multiple Inputs: Includes AUX 3.5mm, USB sound card and U flash disk support so users can play music from a variety of devices and file sources.
• Android APP Control: The Wuzhi Audio Android app lets you rename the Bluetooth device and set a password to avoid accidental connections.
• Compact Form Factor: Small size makes it easy to integrate into DIY speaker cabinets or custom installations without taking much internal space.

Who It's For

The ZK-502A suits DIY audio enthusiasts, makers building powered bookshelf or portable speaker projects, and hobbyists who want app-level control over Bluetooth naming and security. It is particularly useful for setups where multiple amp boards are present and clear identification is helpful.

Those who need iOS app control, advanced DSP tuning, or professional rack-mounted amplifiers should look elsewhere. Also, people who require guaranteed power-saving behavior in every environment may want to test the unit first, as a few users reported inconsistent power-on with the power saving feature.

Pros & Cons

Pros

• High output for size, offering solid loudness and clear midrange for DIY speakers.
• Versatile input options including Bluetooth, AUX, USB sound card and U flash disk for flexible playback.
• Android app control allows renaming and password protection to prevent unwanted connections.

Cons

• App is Android only, so iPhone users cannot access the app features.
• Some customers reported occasional issues with the power saving or power-on behavior, indicating variability in that feature.

Specifications

Our Verdict

The ZK-502A is a practical, budget-friendly amplifier board for DIY speakers and small home audio projects, offering impressive power for its size and useful Android app controls for Bluetooth naming and security. It represents good value for hobbyists who need flexible inputs and easy wireless setup, though iOS users and those expecting flawless power-saving behavior should be aware of the limitations.

Frequently Asked Questions

Can iPhone users control the amp with the app?
No. The Wuzhi Audio app is currently Android only, so iPhone users cannot access app features.

What inputs are supported?
The board supports Bluetooth 5.0, AUX 3.5mm input, USB sound card and U flash disk playback.

What power supply does it need?
The amplifier runs on a DC supply between 9V and 24V as specified by the product.