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A brief discussion on the matching techniques and precautions for power amplifiers and speakers

I. Impedance Matching 1. When matching a tube amplifier (tube machine) with a speaker, the output impedance of the amplifier should be equal to the impedance of the speaker; otherwise, the output power will be reduced and distortion will increase. Fortunately, most tube machines have variable output impedance matching interfaces such as 4-8-16 ohms, making speaker impedance matching simpler. 2. For the impedance matching of a transistor amplifier (solid-state machine) and a speaker ① When the speaker impedance is higher than the amplifier output impedance, there is no other effect except for a certain degree of reduction in output power. ② When the speaker impedance is lower than the amplifier output impedance, the output power increases proportionally, and the distortion generally does not increase or increases slightly, which can be ignored. However, the speaker impedance cannot be too low when matching, such as as low as 2 ohms (referring to two 4-ohm speakers connected in parallel). In this case, only when the amplifier has a large power surplus and uses high-performance high-power tubes and multiple tubes in parallel push-pull, there is generally no effect on such an amplifier. Conversely, for general ordinary amplifiers with not much surplus power, and the pcm and lcm of the amplifier tubes are not large, when the volume is turned up very high, the distortion will increase significantly, and in severe cases, it may damage the speaker. Please pay attention to this. Speaker supplier II. Power Matching 1. In principle, when the rated power of the speaker is inconsistent with the rated power of the amplifier, for the amplifier, its power size is only related to the speaker impedance, and has nothing to do with the rated power of the speaker. Whether the speaker power and amplifier power are the same or not has no effect on the amplifier's operation, but only on the safety of the speaker itself. Invisible speakers V2 subvert the traditional sound emission principle, originating from British NXT technology. Unlike the traditional cone piston vibration method, it uses an innovative drive chip to drive the entire honeycomb panel sound emission surface, which can evenly distribute the sound 180 degrees throughout the space, achieving a 360-degree dead-angle listening effect. No matter where you are in the room, you can enjoy pleasant and beautiful sounds. Built-in self-recovery insurance and filter circuits provide effective protection in the state of sound distortion, and laboratory tests can effectively protect the speakers from being burned out. 2. If the speaker impedance meets the matching requirements, but the power it can withstand is smaller than the amplifier power, then the driving power is sufficient, and it sounds very comfortable. This is often said that the amplifier needs a large reserve power to fully express the full connotation of music, especially the low-frequency part of the music, which is more vivid and powerful. This is a better match. 3. If the rated impedance of the speaker is greater than the rated power of the amplifier, although both can work safely, the power amplifier's driving power seems insufficient, and the loudness will feel insufficient. It often appears that it has already reached saturation, the distortion intensifies, and it still feels powerless. This is a poor match.