Introduction

In today's rapidly evolving Bluetooth landscape, traditional point-to-point Bluetooth audio connections (e.g., phone to speaker) can no longer meet the demands of increasingly complex application scenarios. From synchronized listening instruction in classrooms to museum tour guide systems, from high-energy music in fitness centers to simultaneous interpretation in conference rooms — the market demand for one-to-many, low-latency, and configurable audio broadcasting is growing rapidly.

The EWM104-BT61SP module from Chengdu Ebyte Electronic Technology Co., Ltd. is purpose-built to address this exact need. As a Bluetooth 5.4 dual-mode audio broadcast transceiver module, it supports not only classic Bluetooth audio reception and playback but also breaks through the connection limitations of traditional Bluetooth with LE Audio broadcasting — enabling one transmitter to simultaneously stream audio to multiple receivers.

Product Overview

The EWM104-BT61SP is Ebyte's next-generation audio solution based on the Bluetooth 5.4 specification. It is a dual-mode Bluetooth module supporting both LE Audio (Low Energy Audio) and Classic Bluetooth, powered by a high-performance 160MHz 32-bit dual-core DSP processor.

• Core Positioning: An audio broadcast transceiver module that integrates both transmission and reception functions, supporting multiple audio input/output methods.

Product Variants:

Features & Model Comparison

Core Features

Three Audio Input Methods:

• Bluetooth Wireless Input: Receive audio stream from a phone/computer via Classic Bluetooth

• USB Differential Signal Input: Function as a USB sound card for audio input

• IN_L / IN_R Analog Input: Receive analog audio signals via 3.5mm AUX cable

Two Audio Output Methods:

• OUT_L / OUT_R Analog Output: Output stereo analog signals to an external amplifier or speaker

• Bluetooth Broadcast Output: Transmit audio simultaneously to multiple receivers via LE Audio broadcasting

One-to-Many Broadcasting: One transmitter can broadcast audio to multiple receivers simultaneously, breaking the point-to-point limitation of traditional Bluetooth.

64 Independent Channels: Six address pins (D1~D6) provide 64 channel combinations, effectively preventing signal crosstalk between adjacent areas.

8dBm TX Power: Communication range of over 160 meters in open, clear environments.

AT Command Configuration: Users can configure module parameters flexibly via UART serial AT commands.

Lithium Battery Charging Management: Supports VBAT lithium battery power supply; the VPWR pin also supports charging functionality.

EWM104-BT61SP vs. EWM104-BT61SX

In a Nutshell: The SP variant is the "cost-effective, hassle-free" all-in-one solution; the SX variant is the "performance-maximizing" flexible solution.

Technical Specifications

Application Scenarios

With its unique combination of "transceiver integration, multi-source input, and one-to-many broadcasting," the EWM104-BT61SP is ideal for:

• Bluetooth Stereo Speakers: Serves as the main chip for speakers, supporting wireless Bluetooth playback, AUX wired input, and multi-speaker wireless daisy-chaining (broadcast mode).

• Bluetooth Audio Receivers: Upgrade wired speakers or amplifiers to Bluetooth-enabled devices by receiving audio streams from phones or computers.

• Audio Broadcast Transmitters: In classrooms, gyms, museums, or conference halls, broadcast the instructor's or host's audio to multiple receiver devices simultaneously.

• Audio Receivers: Pair with a transmitter to receive broadcast audio and drive headphones or speakers for personal tour guides, simultaneous interpretation, etc.

• TV Companion Systems: Broadcast TV audio via Bluetooth so that users with hearing difficulties can wear receiver headphones without disturbing others.

• Public Address Systems: Serve as wireless audio relay or auxiliary broadcast nodes for large-area audio coverage.

 WHY choose EBYTE ？

Choosing the Ebyte EWM104-BT61SP means getting more than just a module — you get a complete solution:

• Mature Technology Platform: Based on the latest Bluetooth 5.4 standard, offering strong compatibility, stable performance, and market-validated reliability.

• Complete Development Ecosystem:

• Detailed user manual covering specifications, pin definitions, functional logic, and AT command set

• EWT104-BT61SP test kit with pre-soldered modules, ready to use out of the box

• Hardware design guidelines and soldering instructions to minimize development risk

• Industrial-Grade Quality: Strict quality control ensures stable operation across a wide temperature range of -40°C to +85°C.

• Flexible Technical Support: Professional technical consultation and customized services tailored to specific application scenarios.

FAQ

Q1: What if the transmission range is not satisfactory?
A: First, check the antenna environment to ensure no metal shielding is nearby. Second, verify that the power supply voltage is stable. If needed, switch to the EWM104-BT61SX (IPEX version) with an external high-gain antenna to improve range.

Q2: Why is the module easily damaged?
A: The most common causes are abnormal power supply (excessive voltage or fluctuations) and electrostatic discharge (ESD) . Always adhere to the specified power supply range (VBAT: 3.0-4.4V, VPWR: 4.5-5.5V) and take anti-static precautions (e.g., use an anti-static wrist strap) during handling.

Q3: How do I set up one-to-many broadcasting?
A: Set the transmitter module to TX mode (pin 13 TX/RX connected to GND) and receiver modules to RX mode (pin 13 TX/RX floating). Then configure the same channel address on all modules using the D1~D6 pins (e.g., all pulled high = Channel 0) for broadcast communication.

Q4: How do I reset the module to factory settings?
A: The module has no dedicated RESTORE pin. You can reset module configuration by modifying relevant parameters via the AT command table (refer to Chapter 6 of the manual). For a hardware reset, power-cycle the module.

Q5: Can UART serial communication and audio playback work simultaneously?
A: Yes. AT command communication and audio processing run in parallel. You can send AT commands via UART to query module status or modify configuration while audio is playing.

The EWM104-BT61SP is a benchmark product from Ebyte in the Bluetooth audio domain. It precisely addresses the market's growing demand for one-to-many wireless audio broadcasting. With its rich interface options, flexible operating modes, and industrial-grade quality, it is the ideal choice for building your next-generation Bluetooth audio devices.