Output power is provided only when both the audio input is sufficient and the power supply voltage/current is sufficient. The stronger the input signal and the power supply, the better the available output power. If the power supply voltage is higher, the available output power increases correspondingly. Speakers with different impedances yield different output powers. The impedance of the speaker affects how much power the unit can deliver to it. Practical implications: Ensure your audio source delivers a strong enough input signal for the desired output. Use a power supply that can meet the required voltage and current for the intended listening level. When selecting speakers, be aware that lower or higher impedances will result in different output levels from the same device. Use scenarios: Home stereo setup: With a robust audio source and a stable power supply, you can achieve stronger output as the input and supply meet the requirements. Studio or home theater: When using speakers with different impedances (for example, 4 ohms vs 8 ohms), the unit will produce different output levels; choose speakers and wiring to match the desired loudness. System upgrade: If you upgrade the power supply to a higher voltage within specifications, the device can deliver more output power, improving performance for demanding passages or larger rooms.