OpenAudio Releases KNX Integration Protocol for HOLOWHAS Series Multi-room Streaming Amplifiers

OpenAudio officially launches the exclusive KNX Integration Protocol (Version V1.0, released February 2026) for its HOLOWHAS Series Multi-room Streaming Amplifiers. Based on standard KNXnet/IP text commands for communication and built for the product’s core 8-Zone 8-Source audio architecture, the protocol enables plug-and-play functionality with no complex programming required. It significantly reduces the difficulty of integration with KNX smart home systems and delivers refined, matrix-based intelligent control for whole-home audio setups.

Download the Full KNX Integration Protocol PDF

Core Protocol Infrastructure

Hardware Compatibility

The protocol is optimized for the HOLOWHAS Series’ core configuration of 8 independent audio playback Zones and 8 independent audio Sources, supporting independent dual-dimension control:

• Zone Control: Each playback zone features independent volume adjustment, mute control, and free selection of the audio Source for playback.
• Source Control: Each audio Source supports independent volume adjustment, mute control, and manual selection of physical input interfaces (HDMI, Bluetooth, AirPlay 2, etc.).

Standard 3-Level KNX Group Address Format

The protocol adopts a clear, maintainable Main Group/Number/Function 3-level address structure, defining a unified address rule for all control operations:

1. Main Group: Distinguishes control objects – 1 = Zone Control, 2 = Source Control.
2. Number: Specifies the serial number of the exact control object (1-8 for both Zones and Sources, corresponding to Zone 1-8/Source 1-8).
3. Function: Specifies the type of operation on the object, defined by function codes with core rules as follows:

Core Control Specifications

Zone Control Address Table

Covers all Zones 1-8, with each zone assigned three independent addresses for volume, mute, and Source selection (all follow the 3-level address rule):

Source Control Address Table

Covers all Sources 1-8, with each source assigned three independent addresses for volume, mute, and input interface selection:

Source Physical Input Interface Mapping

The numeric values for the Source Selection function code (3) map one-to-one with mainstream physical and streaming input interfaces, supporting all core audio access methods on the market:

Standard KNXnet/IP Command Format

The protocol uses a unified write [Address] [Value] command format with no additional complex syntax, executed directly via KNX bus broadcasting. Core control examples are as follows:

 Zone Control Examples

1. Set Zone 3 volume to 50%: write 1/3/1 128
2. Mute Zone 5: write 1/5/2 1
3. Switch Zone 8 to play from Source 3: write 1/8/3 3

Source Control Examples

1. Set Source 4 volume to 70%: write 2/4/1 179
2. Switch Source 2 to HDMI ARC input: write 2/2/3 2
3. Switch Source 7 to Google Cast: write 2/7/3 7
4. Mute Source 6: write 2/6/2 1

Streamlined Integration Process & Core Advantages

Configuration Responsibilities (No Programming, Plug-and-Play)

Designed with a Transparent Receiver + Address Binding Only architecture, the protocol clearly defines configuration duties for the audio system and KNX controller, eliminating complex engineering setup:

1. OpenAudio Audio System Side (Receiver & Executor): Automatically monitors the KNX bus for incoming commands and parses addresses and values. No configuration required (no ETS software, no database import) – true plug-and-play functionality.
2. KNX Controller Side (Sender, Panel/Hub): Only needs to complete binding of physical buttons/sliders to group addresses in the ETS Engineering Tool Software (graphical operation, similar to setting shortcuts). No coding or KNX system redesign is needed.

Complete Control Flow

1. The user performs an action on the KNX panel (button press/slider adjustment).
2. ETS triggers the pre-bound group address and corresponding value.
3. The standard write [Address] [Value] command is broadcast over the KNX bus.
4. The OpenAudio amplifier receives and parses the command.
5. The amplifier executes the corresponding operation (volume adjustment/mute/Source switch/input switch).

Core Protocol Advantages

1. Standardized Structure: Built on the standard KNX 3-level group address design, compatible with the KNXnet/IP protocol and all mainstream KNX smart home systems.
2. Refined Control: Full independent control of 8 Zones and 8 Sources with precise 0-100% volume adjustment, meeting the demands of complex whole-home audio scenarios.
3. Rich Interfaces: Sources support both physical interfaces (LINE IN, HDMI ARC, etc.) and mainstream streaming interfaces (AirPlay 2, Google Cast, etc.), adapting to all audio access scenarios.
4. Lightweight Integration: No programming, zero configuration (amplifier side) and only address binding (KNX side), drastically reducing integration difficulty and engineering costs.
5. Seamless Compatibility: Based on the core KNX group address communication rules, seamless communication is achieved as long as both parties follow the agreed address and value definitions – no cross-system compatibility issues.