Model 1.5.1 Key features and benefits fidelity wireless audio Supports AAC and aptX HD codecs for richer, clearer sound when streaming to speakers or enclosures. Robust transmission and easy pairing Uses the protocol aptX HD for better quality and stability. Clear or resettable pairing information to simplify re pairing. Default configuration uses 3031 for aptX HD. Phone volume synchronization Volume on the connected phone can be synchronized with the module for consistent listening levels. Flexible control and integration Includes a serial port for AT commands at 115200 baud for advanced setup and automation. Antenna flexibility Supports an external antenna option to improve range and signal stability. Android app features The Android app allows modification of Bluetooth name. The Android app allows setting or changing pairing password. The Android app allows creation and application of custom EQ profiles. The Android app allows switching prompt tone to suit user preference. Isolated DC power supply for clean installations DC isolated power supply helps prevent ground loops and noise. Ideal for modifying speakers and amplifiers. Practical for adding Bluetooth to cars to reduce common ground current sound and noise. Applications and use scenarios Car audio retrofit Add Bluetooth capability to an existing car stereo or amplifier with an isolated power supply to minimize ground noise while preserving audio quality. Speaker box modernization Upgrade speaker boxes or enclosures with wireless streaming via AUX input, enjoying AAC/aptX HD quality without sacrificing wired inputs. DIY and professional audio projects Use the AT command interface for custom control or automation in integrated audio systems. Bluetooth identity and EQ settings for a tailored listening experience across multiple devices. Compatibility and suitability Designed for speaker boxes and audio enclosures with AUX input Suitable for car audio upgrades and DIY audio installations Android app for Bluetooth name, password, EQ, and prompt tone modification Serial AT command interface for integration at 115200 baud DC isolated power supply included or recommended for installations requiring noise reduction Technical overview (at a glance) Version: 1.5.1 Codecs: AAC, aptX HD Input: AUX audio input Control: Serial AT commands (115200 baud) protocol: aptX HD (default 3031) Power: DC isolated power supply Antenna: supports external antenna option Language support: Android app supports any language for Bluetooth name modification Note: This description preserves the original product scope and specifications while presenting clear, customer friendly information about benefits, compatibility, and practical usage.