Key principle: Speakers with different impedances will have different output powers. This means the loudness and headroom you experience depend on the impedance match between the speaker and the amplifier. How power is delivered: Output power is available only when both the audio input level is sufficient and the amplifier can supply adequate voltage and current. Without a strong input signal and proper power supply, the expected output cannot be reached. Effect of supply voltage: If the supply voltage is higher, the relative output power can increase, providing more headroom and potential volume for the same input level. Practical guidance: To achieve the intended performance, pair speakers with an amplifier and power supply that can meet the impedance and power requirements. Inadequate input signal or insufficient supply will limit output regardless of speaker capability. Use scenarios: 1) Home stereo setup with mixed impedance speakers: Ensure the amplifier and power supply can deliver adequate current for the lowest impedance speaker to maintain consistent volume. 2) Desktop or compact audio system: Provide a strong input signal and a power supply capable of delivering sufficient voltage/current to reach the desired loudness without distortion. 3) Small event or multimedia display: Design the system so that the input level and supply are ample to support the target output across the chosen speaker impedances, ensuring clear sound at the required volume.