Audison SPM4 4-Channel Stereo Passive Mixer

by Audison


  • Stereo passive mixer (unpowered) featuring 4 input channels and 2 output channels, designed for active OEM multi-way systems where each speaker is powered by one specific amplified channel. SPM4 mixes audio through 4 audio transformers specifically developed to achieve very low distortion and highly linear acoustic response.
  • SPM4 provides the ability to mix the midrange/woofer and tweeter channels coming from the amplifier and supply one single mid-high channel. The Ch1(L/R) channels feature two inputs, one features an inverting input compared to Ch2 (L/R) channels; the mixing process often gives better results when one of the two channels undergoes a 180° dephasing.
  • SPM4 is especially recommended to extend the number of inputs of the Audison digital processors or amplifiers with built-in DSP because they feature a De - equalizer (De - Eq). In that case, any possible non - linear acoustic emissions due to the mixing of the pre-existing filtered channels are duly compensated.


  • Max input power W (RMS): 25
  • Max input power W (peak): 50
  • Output Gain dB: - 3
  • T.H.D. (input power max)
    • 0.5% (100Hz)
    • 0.05% (1kHz)
    • 0.05% (10kHz)
  • Bandwidth Hz ( - 3dB): 15 ÷ 75k
  • Crosstalk dB (10kHz): > 55
  • Input impedance: Ω 32
  • Out impedance: kΩ 10
  • Phase inverter: Ch1 (left & right)
  • W x H x D mm in.: 103.5 x 36.5 x 86.5 4.07 x 1.43 x 3.40
  • Weight (kg / lb.) kg lb.: 0,24 0.53