It is obvious from the example above that adequate amplifier power is necessary to provide an accurate portrayal of music. This is especially true when attempting to reproduce realistic levels, or when driving inefficient speakers. However, even small efficient speakers may require copious amounts of power to cleanly reproduce transient peaks. In the final analysis, it is difficult to have too much power. While a small amplifier of only a few watts output can produce surprising average loudness, the dynamic peaks will usually suffer unless the sensitivity of the speaker is very high.
Many individuals I have spoken with are concerned with having "too much" power. The perception is that an amplifier with an output greater than that recommended by the speaker manufacturer would be likely to damage the speaker. This is not necessarily so. Interestingly, an underpowered amplifier is more likely to cause speaker damage! Sound strange? Not really, once you understand what is happening. When an amplifier is over-driven, it "clips" the wave-form. What was a clean sine wave becomes a distorted, almost square, wave.
A square wave is extremely difficult for a speaker to reproduce, as it requires virtually instantaneous starting and stopping of the diaphragm. At sufficient power levels, the tweeter will simply die trying to reproduce this wave-form. A given tweeter rated to handle 50 watts of clean undistorted sine-wave power, will be capable of handling only a fraction of that amount in square-wave input. As you can see, clean, undistorted power is the key. A watt amplifier, constantly driven to clipping, is more dangerous than a watt amplifier that is never taxed.
Of course, let reason prevail. I am not saying that speakers can handle endless input, they cannot. However, extra power does not mean that speaker damage is bound to occur. If common sense is used, any size amplifier can be employed. Many factors influence amplifier choice.
Some of the more important considerations are speaker type efficiency or sensitivity , room size, the type of music you listen to, and, most importantly, how loud you like to listen and even how far one sits from the speakers.
In an extreme example, one might own an inefficient loudspeaker, have a very large room, and like to listen to pipe organ music at realistic levels.
The next listener, with the same speaker, may have a much smaller room and prefers chamber music at background levels. Here, power requirements might be only one-tenth to one-fourth those required in the previous illustration. Requirements do vary widely. It is wise to take all factors into account before making a decision regarding the amount of power necessary for your situation.
Love is the music. Music makes you feel. Pay attention to Continuous Power and the wattage your amplifier is putting out, and stack that up against the recommended amplification levels on your speaker. So, why should you care about sensitivity? When distance from the speaker and power applied are the same, a speaker with a lower sensitivity would sound quieter than a speaker with a higher sensitivity. If you increase the distance between you and your speakers, volume drops off quickly. You can expect to see a 6dB falloff every time you double the distance between your speakers.
For example, a HiFi system in a lounge is going to have different requirements than a home cinema set up. Larger rooms require larger speakers with higher sensitivity or more powerful amplifiers than you might have previously considered, whilst intimate spaces can effectively be scaled back in terms of sensitivity or power.
All of which brings us to:. Blowing up your speakers or destroying your amplifier, of course. There are a few ways you can achieve these undesirable outcomes, but by far the most common are:. This completely destroys the speaker, which is less than ideal. Doing so will cause the amp to overheat, start burning itself up and send clipped signals to your speakers, creating horrible distortion and high frequency energy which can break your speakers and your amplifier.
Another good example is Q Acoustics i bookshelf speakers. These compact and award-winning speakers have a nominal 6ohm impedance, a sensitivity of 86dB and a recommended power between 15 and 75 watts. Doing a little shopping around and comparing numbers will ensure that you find a set of speakers and amplifier which not only work together, but sound amazing — and will do for decades to come, with the right care.
Understanding speaker and amplifier matching terminology Key to ensuring effective synergy between your speakers and your amplifier is having a basic grasp of HiFi vocabulary. The bottom line: Pay attention to Continuous Power and the wattage your amplifier is putting out, and stack that up against the recommended amplification levels on your speaker.
0コメント