ZK-502T Bluetooth Amplifier Board with Treble and Bass Control

In this review the ZK-502T Bluetooth amplifier board is presented as a compact, affordable stereo amp board aimed at DIY audio enthusiasts who want more control from passive home speakers. The biggest reason to consider it is the combination of the TPA3116D2 HIFI chip with dedicated treble and bass control, which delivers surprisingly clean, punchy sound for its size when powered correctly. It is best for hobbyists who will install it into a small cabinet or project and who value tuning tone and efficient power use over premium industrial design.

Key Features

• TPA3116D2 HIFI chip: Provides stereo dual-channel output with low distortion for reliable continuous high-power operation.
• 50W per channel: Delivers strong output suitable for bookshelf or small floorstanding passive speakers when supplied with adequate voltage and current.
• Wide DC input: Runs from DC 9-24V so it works with a range of adapters and battery setups; recommended above 12V/3A for best results.
• Bluetooth 5.0 and AUX: Offers wireless streaming up to about 49 ft in open space and a 3.5mm auxiliary input for non-BT sources.
• Treble & bass knobs: Physical tone controls let you tame excessive highs or lift low end for a more cinematic listening experience.
• Protection features: Built-in overheat, over-voltage, under-voltage and circuit protection help safeguard the amp and connected speakers.

Who It's For

This board is ideal for DIY audio builders who want a compact, low-power amplifier with on-board tone shaping and Bluetooth streaming. It's a strong choice for powering passive speakers in a bedroom, small living room or custom enclosure where compactness and tweakable sound matter more than show-piece fit and finish.

It is not the best pick for buyers seeking premium industrial design or plug-and-play high-end home theater components; some customers note the build quality is utilitarian and Bluetooth pairing can be inconsistent on rare occasions, so those needing flawless wireless reliability might prefer a fully assembled commercial receiver.

Pros & Cons

Pros

• Good value for money with 50W x 2 power and tone controls at a low price point.
• Flexible power options thanks to the wide DC 9-24V input, allowing battery use for portable setups.
• Useful protection circuitry reduces risk during extended use or voltage issues.
• Compact footprint and easy to mount inside custom projects.

Cons

• Build quality and enclosure finish are basic; expects DIY installation and careful mounting.
• Bluetooth connectivity is mixed for some users, with occasional pairing or range quirks.

Specifications

Amplifier chip	TPA3116D2
Power output	50W + 50W
Working voltage	DC 9-24V (recommended above 12V/3A)
Bluetooth	Bluetooth 5.0 (approx 49 ft open range)
Inputs	Bluetooth 5.0, 3.5mm AUX
Protection	Overheat, over-voltage, under-voltage, circuit protection
Power connector	5.5 x 2.5mm (compatible with 5.5 x 2.1mm)

Our Verdict

The ZK-502T is a practical, cost-effective amplifier board for DIYers who want genuine power, tone controls and flexible power options without paying for a finished chassis. While the physical build is basic and Bluetooth can be variable, the sound quality and protection features make it a smart value purchase for small-room audio projects and custom speaker builds.

Frequently Asked Questions

Does it include a power supply?
The standard board listing does not always include a power adapter; a DC 19V 4.74A adapter is shown as a compatible option and a recommended supply is 12V/3A or higher for best performance.

Can I use it with a battery?
Yes, the wide 9-24V input allows battery use; customers report good run time with suitably sized batteries when current capacity is sufficient.

How reliable is Bluetooth on this board?
Bluetooth 5.0 provides longer range in open spaces, but some users report occasional pairing quirks; use the 3.5mm AUX if you need rock-solid wired playback.