The Ebyte EWM104-BT61SX (stamp-hole SMD) and EWM104-BT61SP (evaluation board) are industrial-grade BLE 5.2 audio + data transmission modules operating at 2.4 GHz. Built on a high-integration SoC, they support Bluetooth LE Audio (Auracast™ broadcast audio) and the LC3 low-complexity codec, enabling simultaneous wireless audio streaming and bidirectional data communication in a single compact module.
Technical Specifications
| Models | EWM104-BT61SX (SMD stamp-hole) | EWM104-BT61SP (evaluation board) |
| Bluetooth Standard | Bluetooth LE 5.2 (LE Audio ready) |
| Audio Feature | Auracast™ Broadcast Audio, LC3 codec, isochronous channels (BIS/CIS) |
| Operating Frequency | 2.400 – 2.4835 GHz (ISM Band) |
| Communication Interface | UART / SPI |
| Power Supply | 3.3 V DC |
| Module Dimensions | 13 × 19 mm (EWM104-BT61SX) | 47 × 49 mm (EWM104-BT61SP) |
| Antenna Interface | Onboard PCB antenna / IPEX connector |
| Operating Temperature | -40℃ to +85℃ (industrial grade) |
| Certifications | FCC Part 15, CE (RED) 2014/53/EU, RoHS |
| Data Updated | April 2026 |
Product Details
Auracast™ Broadcast Audio — One-to-Many Wireless Audio
The EWM104 series implements the Bluetooth SIG Auracast™ broadcast audio profile, enabling a single transmitter to stream high-quality audio to an unlimited number of receivers simultaneously — without pairing. This is the foundation for public audio systems, hearing loop replacements, silent disco, and multi-zone audio distribution in commercial and industrial environments.
LC3 Codec — High Audio Quality at Low Bitrate
The LC3 (Low Complexity Communication Codec) delivers CD-quality audio at bitrates as low as 32 kbps — significantly outperforming SBC at equivalent bitrates. This enables longer battery life, lower RF duty cycle, and reduced latency (<10 ms end-to-end) compared to classic Bluetooth audio, making EWM104 ideal for hearing aids, wireless headsets, and industrial intercom systems.
Simultaneous Audio + Data — Dual-Mode BLE Operation
Unlike dedicated audio chips, the EWM104 supports concurrent BLE audio streaming and GATT data communication over isochronous (BIS/CIS) and asynchronous channels. This enables real-time audio monitoring combined with sensor data uplink — critical for smart hearing devices, industrial voice + telemetry nodes, and conferencing systems.
Ideal Applications
| Public Audio Systems | Auracast broadcast to hearing aids, assistive listening devices, airport/stadium PA systems |
| Wireless Headsets & Earbuds | True wireless stereo (TWS) with LC3 codec, ultra-low latency audio for consumer and professional use |
| Industrial Intercom | Voice + data simultaneous transmission for factory floor, warehouse, and field worker communication |
| Hearing Aids & Medical Audio | LE Audio compliant hearing device streaming with low power and high speech intelligibility |
| Smart Conference Systems | Multi-microphone BLE audio aggregation, wireless speaker arrays, meeting room audio distribution |
| IoT Audio Monitoring | Remote acoustic sensing combined with BLE data uplink for predictive maintenance and security |
FAQ
Q1: What is the difference between EWM104-BT61SX and EWM104-BT61SP?
A: The EWM104-BT61SX is a compact SMD stamp-hole module (13×19 mm) for direct PCB integration into end products. The EWM104-BT61SP is a fully assembled evaluation board (47×49 mm) with USB interface, antenna, and breakout pins — ideal for rapid prototyping and firmware development before mass production.
Q2: Does this module support Auracast™ broadcast audio as defined by the Bluetooth SIG?
A: Yes. The EWM104 series implements the Bluetooth SIG Auracast™ Broadcast Audio specification based on BLE 5.2 isochronous channels (BIS). It supports one-to-many audio streaming without pairing, compatible with Auracast-enabled receivers including hearing aids, earbuds, and assistive listening devices.
Q3: What audio codec is supported, and what is the audio latency?
A: The module supports the LC3 (Low Complexity Communication Codec) as standardized in Bluetooth LE Audio. LC3 achieves high audio quality at 32–320 kbps with end-to-end latency as low as <10 ms (CIS unicast mode), significantly lower than classic Bluetooth A2DP/SBC.
Q4: Can the module transmit audio and data simultaneously?
A: Yes. The EWM104 supports concurrent operation of isochronous audio channels (BIS/CIS) and asynchronous GATT data channels, enabling simultaneous audio streaming and sensor/control data exchange over a single BLE 5.2 link.
Q5: Is this module compatible with Apple, Android, and Windows Auracast receivers?
A: Auracast™ is an open Bluetooth SIG standard. The EWM104 is compatible with any Auracast-compliant receiver. Native Auracast support is available on Android 13+ and Windows 11 (24H2+). Apple LE Audio support is device-dependent — check Apple's current LE Audio roadmap for the latest status.
Q6: How do I configure and develop with this module?
A: The UART interface supports AT command configuration and Ebyte's USB configuration tool for basic parameter setup. For custom audio profiles, BIS/CIS topology, and LC3 codec tuning, the underlying SoC SDK (provided separately) supports full firmware customization via standard C toolchain.
Q7: What certifications does the EWM104 carry?
A: The EWM104 series holds FCC Part 15 and CE (RED) 2014/53/EU certifications, with RoHS compliance. Modular FCC certification may reduce end-product re-certification scope — contact Ebyte for grant documentation.
Q8: What is the free sample policy?
A: This listing provides 1 sample unit at $0.10 (handling fee), limited to 2 pcs per person across all Ebyte sample models. Dispatched within 2 business days via DHL/UPS/FedEx. Bulk pricing, OEM/ODM, and custom firmware services are available — contact Ebyte sales for a quote.
