Square Audio High-power Portable Subwoofer with 40W Output and Lithium Battery

This square audio subwoofer is built to deliver high-power sound without the restrictions of a mains cable. With a 40W rated output and a frequency range stretching from 100Hz to 20kHz, it produces a balanced audio profile that suits everything from bass-heavy music to clear speech for announcements or karaoke. The unit operates on a robust lithium battery system using 18650 cells, so you can take it from your desk to the park without hunting for a power socket. It features card insertion for direct music playback, a recording function, a voice prompt system, and a money collection broadcast mode – making it especially useful for market traders, outdoor fitness instructors, or anyone who needs portable amplified sound with added utility features. Available in two sizes, the 4-inch version with a standard 4-section 18650 battery and the 6.5-inch version with a standard 6-section 18650 battery, this speaker covers a wide range of volume and runtime needs.

Features and Construction

The subwoofer is designed for practical, high-volume use across multiple scenarios. Its power system and control features set it apart from basic portable speakers, especially for those who need voice prompts or money collection broadcast.

High-Power Audio

With a 40W rated power, this subwoofer can fill a medium-sized room or outdoor area with sound. The 100Hz-20kHz frequency range delivers a solid bass foundation while maintaining clarity in the mids and highs – suitable for music, karaoke, or spoken announcements.

Built-in Lithium Battery

The speaker uses 18650 lithium cells, with the 4-inch model running on a standard 4-section pack and the 6.5-inch model on a standard 6-section pack. This provides cordless portability for outdoor use, fitness sessions, or mobile sales stands.

Versatile Control Features

Card insertion allows playback directly from a microSD card or USB drive. The recording function and voice prompt system make it easy to navigate settings, while the money collection broadcast is a practical addition for cash-based transactions at markets or events.

Uses and Placement

This subwoofer is intended for scenarios where portable, high-power audio is needed. Its feature set supports both entertainment and professional tasks.

Desktop and Home Use

Place it on a desk or shelf for enhanced computer audio or casual music listening. The voice prompt system makes it simple to control playback without reaching for a phone.

Fitness and Outdoor Use

Take it to the gym, a park, or an outdoor fitness class. The battery power eliminates the need for an extension lead, and the 40W output is loud enough to motivate a group workout.

Karaoke and Square Dance

Plug a microphone into the 6.5-inch model (which includes a single microphone) for karaoke evenings or community square dance sessions. The money collection broadcast feature is especially useful for busking or charity events.

Benefits and Buying Value

The subwoofer offers clear practical advantages for those who want portable audio with extra functionality.

Cordless Convenience

The lithium battery means you can set up anywhere – from a remote picnic spot to a market stall – without depending on mains power. The choice between 4-inch and 6.5-inch models lets you match battery capacity to your typical runtime needs.

Multi-Function Utility

Recording, card playback, voice prompts, and money collection broadcast turn a basic speaker into a practical tool for traders, instructors, or performers. These features are built in, so you don't need separate devices.

Why Choose This Product

If you need a portable speaker that does more than play music – with voice guidance, recording capability, and a dedicated money collection mode – this subwoofer delivers those functions in a single, self-powered unit. Its 40W output and lithium battery make it suitable for both indoor and outdoor use.