Hits:Updated:2018-04-23 09:04:20【Print】
Many people are concerned about this issue because it involves the issue of whether the speakers are easily burned. If we discuss it in isolation, we will not have the correct result. Whether it is speaker power amplification or vice versa, the result is both right and wrong! A key factor is whether the sound output capability of our equipped speakers can meet the sound pressure requirements of our site and has a margin. Otherwise, this discussion about power matching will never have the correct answer. .
Let's explore what happens in different situations if:
one. The output capacity of the speaker is not enough to meet the needs of the application site for sound pressure. In this case:
1. When the amplifier's output power is lower than the speaker's power, the result is that the amplifier is turned to overload, resulting in clipping distortion, but also can not meet the speaker's need for power, obviously, the speaker can not output the maximum sound pressure it can output, naturally, It can't satisfy our need for sound pressure. On the surface, the speakers seem to be safe, but the sound is not enough and the distortion is not good, but the reality is that the power amplifier has produced clipping distortion, and its output has become Square wave characteristic (also with DC component) audio signal, and in this signal, the proportional component of the high-frequency signal is much larger than the normal music signal. The electric power allocated to the speaker tweeter through the speaker divider is much higher than normal. The value will exceed the capability of the tweeter itself and the tweeter will be damaged. At the same time, too large square wave signal components will cause overload damage to the woofer unit.
2. When the amplifier's power is greater than the speaker's acceptable power, such as twice as big (according to the principle of the best sound, need to be configured), due to our need for sound pressure and forcing the amplifier to need full power or even overload output to drive the speaker work The speaker will work for a long time in excess of its rated power and will inevitably be damaged, usually damaging the woofer unit.
in conclusion:
When we configure the speakers, the number of speakers must be sufficient. We cannot reduce the quantity due to budget constraints (this is a contradiction. If it is hard, it will cause trouble for our own after-sales and collections), we must The speaker system output capacity is large enough and has enough margin, at least 20 times, about ten times, this is a conservative figure, because the music signal is dynamic, the dynamic range of the signal is easily over 100DB (hundred thousand times), For example, in a theater, according to the demand for sound pressure, the required power is converted to 240 W by the sensitivity and other data. Then the power of the system we allocate to it needs to be kept at a 2400 W with ten times the margin. Gentle), in this way, we can ensure that the sound system can deliver good distortion-free sound and have a high degree of safety and stability. Of course, such systems will cost more than those without power margin, but it will bring The user will have a high level of service and a high level of stability. On the contrary, those low-cost systems that do not have power margins will often work because there is no power margin. In the overload state, the sound is not good, but it may also require frequent maintenance. The user will be charged with high use costs and the customer's satisfaction with the sound will not affect the business. Unfortunately, many of us Can't see this.
II. The speaker has enough output capacity and sufficient margin to fully meet our sound pressure output needs, in this case:
1. When the amplifier's power is less than the speaker's power, the result is that the amplifier is turned to overload, and it can't meet the speaker's need for power. Obviously, the speaker can't output the maximum sound pressure it can output. Naturally, it can't satisfy us. The need for sound pressure, of course, is different from that of (a). Because the output capacity of the speaker is sufficient and there is a margin left, the sound pressure of the venue can still be satisfied although it does not reach the output sound pressure it should have. The need does not have much margin. The amplifier usually does not necessarily need to be overloaded. Therefore, the actual situation will be better than the situation (1). However, it wastes the power of the speaker system and wastes funds. Achieve proper performance.
2. When the amplifier's power is greater than the speaker's acceptable power, such as more than double (according to the principle of the best sound, need to be configured), when the speaker system itself has enough power headroom, usually much lower than its rated power Under the condition that we can already meet our need for sound pressure, then, the power that the amp usually loads into the speaker can be much lower than the rated output power of the amp, and there is a large amount of power reserve to cope with the instantaneous super signal peak. The system does not have the opportunity to overload the clipping. Naturally, there will not be a long period of excess power loading on the speaker system. The entire system will work in a relaxed state and the sound will be the best. The stability and security of the entire system will be sufficient. The guarantee that the system maintenance and repair work can be reduced to a minimum, and the user's use cost will be reduced to a minimum. This is the so-called high purchase and low use. Since the guest's satisfaction with the sound is the highest, it is very helpful to the business.
in conclusion:
This is the best form of system collocation, with the greatest comprehensive economy and long-term economy. As long as the investor has a full understanding of this point and has a sufficient share in the budget, the investor will receive the maximum return. As a project trader can correctly understand this point, for Party A, but also for ourselves, we should fully communicate with Party A to make him understand this.
In the field of professional sound reinforcement, the configuration of audio equipment is very elegant, in which the configuration of amplifiers and speakers is the most important. Although some speaker products use instructions to recommend the specific brand or model of the amplifier, but still There are limitations, because users often face many models of power amplifiers, no way to start.
There are many aspects involved in the configuration of amplifiers and speakers, such as the choice of power amplifier brand, power tube type, and what kind of power amplifier should be configured for low-sensitivity speakers. The specific configuration of the amplifier and speaker is generally related to the designer's experience, preferences, listening habits and other factors, and it is difficult to find a unified standard. Sometimes we will encounter some users or designers to configure the amplifier with smaller power amplifiers in order to save money, and some users configure the power amplifiers for the speakers with a so-called "power reserve". Obviously, this is not appropriate. Importantly, this configuration can cause damage to the device. In the amplifier and speaker configuration, power amplifier power is indeed the key, that is, the principle of determining the power amplifier should be unified.
As we all know, after the acoustic design of the hall, we need to determine the speaker power based on a series of calculations, and then determine the amplifier power from the speaker power. However, how can the two powers be matched to achieve the best match?
First of all, in the 20Hz~20kHz of the human ear listening domain, the music signals that really concentrate a large amount of energy are generally in the middle, low, and frequency bands, and the high-frequency band energy is only equivalent to 1/10 of the energy in the middle and low frequency bands. Therefore, the general speaker treble loss power is much lower than the bass horn, in order to balance the bass and bass; and the power amplifier is like a current modulator, which controls the input audio signal, the output of different sizes of current to the speaker, so that the size of Different sounds, under certain impedance conditions, it is actually very easy to make 400W or several times the output power of a nominal 200W power amplifier, but the distortion (THD) of the power amplifier will be greatly increased. This kind of distortion is mainly caused by The high-frequency harmonics in the medium and low-frequency signals have higher distortion, and the higher the harmonic energy of high frequencies, these high-frequency distortion signals will all enter the tweeter with the high-frequency music signals. This is why the low-power amplifier pushes Big speakers can cause burning timbre. In the concept of many people, only the amplifier power is high, it is possible to burn speakers. Although some amplifiers have no indication of distortion, distortion may occur during use because the device configuration is already inherently inadequate. At this point, the distortion indication has lost its meaning. Moreover, due to the limitations of the user's experience and quality, distortion of the amplifier is often easily overlooked.
Secondly, there is a certain relationship between the power configuration of the amplifier and speaker and the target loudness and the occasions used. Under a certain target loudness, the dynamics of the music signal should be fully guaranteed on every piece of equipment. If the power of the amplifier is too large, the gain is set to be small, the loudness has reached the required level, but the gain of the amplifier is limited. The dynamic range of the signal. Therefore, power amplifier power can not be too large; otherwise, since waste of money, it will bring loudness and music dynamics can not take into account and the speaker overload. According to past experience, there are differences between places such as general languages, music venues, and dynamic events such as disco.
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