Audison Accessories SPM4

SPM4 Accessories | 4-Channel Stereo Passive Mixer | For Active OEM Multi-Way Systems

The Audison SPM4 is a high-quality, 4-channel stereo passive mixer designed specifically for active OEM multi-way audio systems, where each speaker is powered by its own dedicated amplified channel. Ideal for factory systems with multiple amplified outputs, the SPM4 simplifies signal routing by passively summing inputs into two clean stereo outputs—without adding power or introducing noise.

Built with four custom-developed transformers, the SPM4 ensures ultra-low distortion and a highly linear frequency response, making it a reliable and transparent solution for integrating OEM signals into aftermarket processors, amplifiers, or DSPs.

Its passive, unpowered design means zero additional noise or signal coloration, while maintaining compatibility with a wide range of OEM audio setups. Whether you’re consolidating tweeter, midrange, and woofer channels or integrating full-range factory outputs, the SPM4 offers a clean and elegant solution for audio summing in complex installations.

Key Features

• 4 Input to 2 Output Passive Summing Mixer
• Designed for OEM Multi-Way Systems: Perfect for setups with individual amplified channels per speaker
• Transformer-Based Design: Custom transformers ensure minimal distortion and maximum signal integrity
• No Power Required: Passive design means silent, reliable operation with no external power
• Highly Linear Acoustic Response: Maintains natural sound character during mixing
• Compact and Easy to Integrate: Ideal for use in tight spaces or behind dashboards