When purchasing a new amp, you probably will take a look at the technical specifications. An often found parameter is the frequency response. This parameter whilst significant does not tell the full story concerning how great the amplifier will sound. I will clarify the meaning of this phrase and also give a few recommendations on how to interpret it while looking for an amplifier. An amplifier is built to magnify a sound signal enough in order to drive a couple of audio speakers to medium or higher volume. Producers generally present the frequency range over which the amp functions. Generally a lower and upper frequency are given, for instance 20 Hz - 20 kHz. This specification indicates that the amplifier can amplify music inside of this frequency range. However, there is certainly a lot more to understanding the amplifier's functionality than simply taking a look at these numbers.
An amp will enlarge a sound signal which is inside the frequency response range. This range is specified by listing 2 frequencies: a lower and also upper frequency. For instance, the lower frequency may be 20 Hz and the upper frequency 20 kHz. Using this specification it seems the amplifier would be able to function as a HIFI amplifier. You may very well be lured to select an amplifier that gives the greatest frequency response. Yet, there is more to understanding an amplifier's overall performance than just realizing this simple range. The truth is, an amplifier that has a frequency response from 10 Hz to 30 kHz can actually have much worse audio quality than an amp which offers a frequency response from 20 Hz to 15 kHz. Different manufacturers appear to utilize different methods in order to define frequency response. Usually, the frequency response shows the standard operating range of the amplifier. Inside this range, the amp gain is essentially constant. At the upper and lower cutoff frequencies the gain is going to drop by at most 3 decibels.
However, numerous companies disregard this particular established practice. They push the lower frequency and upper frequency to where the amplifier barely provides any kind of gain. Furthermore, these figures tell absolutely nothing about how linear the amplifier is operating within this range. A complete frequency response graph, on the other hand, will demonstrate if there are any peaks and valleys and also show how the frequency response is to be interpreted. Peaks along with valleys might cause colorization of the sound. Ideally the gain of the amp should be linear through the entire operating range. You additionally want to look at the conditions under which the frequency response was calculated. You generally are not going to find any kind of information about the measurement conditions, however, in the producer's data sheet. The fact is that many amps are going to behave differently with different speaker loads. This is due to the fact that various speaker loads can cause changes to the behavior of the output power stage of the amp.
This change is most detectable with many digital amplifiers, also called Class-D amps. Class-D amplifiers employ a lowpass filter in their output to be able to reduce the switching components which are produced by the internal power FETs. Then again, the frequency response of the amp now depends upon the speaker load since the behavior of this lowpass filter is affected by the load impedance. Normally the lower the loudspeaker load impedance the lower the upper cut-off frequency of the amplifier
Generally contemporary digital or "Class-D" amps can have changes in the frequency response with different loads. The reason is the fact that Class-D amplifiers utilize switching FETs as the power phase which generate a lot of switching components. These components are eliminated with a filter that is part of the amplifier. A varying speaker load is going to impact the filter response to a point. Usually the lower the loudspeaker impedance the lower the maximum frequency of the amp. In addition, the linearity of the amplifier gain will depend on the load. Some amp topologies offer a way to compensate for changes in the amplifier gain with various loudspeaker loads. One of these approaches uses feedback. The amplifier output signal following the interior lowpass is input to the amplifier input for comparison. If not created adequately, this technique could potentially cause instability of the amplifier though. One more technique is to offer specific outputs for various loudspeaker impedances that are connected to the amplifier power stage through audio transformers.
An amp will enlarge a sound signal which is inside the frequency response range. This range is specified by listing 2 frequencies: a lower and also upper frequency. For instance, the lower frequency may be 20 Hz and the upper frequency 20 kHz. Using this specification it seems the amplifier would be able to function as a HIFI amplifier. You may very well be lured to select an amplifier that gives the greatest frequency response. Yet, there is more to understanding an amplifier's overall performance than just realizing this simple range. The truth is, an amplifier that has a frequency response from 10 Hz to 30 kHz can actually have much worse audio quality than an amp which offers a frequency response from 20 Hz to 15 kHz. Different manufacturers appear to utilize different methods in order to define frequency response. Usually, the frequency response shows the standard operating range of the amplifier. Inside this range, the amp gain is essentially constant. At the upper and lower cutoff frequencies the gain is going to drop by at most 3 decibels.
However, numerous companies disregard this particular established practice. They push the lower frequency and upper frequency to where the amplifier barely provides any kind of gain. Furthermore, these figures tell absolutely nothing about how linear the amplifier is operating within this range. A complete frequency response graph, on the other hand, will demonstrate if there are any peaks and valleys and also show how the frequency response is to be interpreted. Peaks along with valleys might cause colorization of the sound. Ideally the gain of the amp should be linear through the entire operating range. You additionally want to look at the conditions under which the frequency response was calculated. You generally are not going to find any kind of information about the measurement conditions, however, in the producer's data sheet. The fact is that many amps are going to behave differently with different speaker loads. This is due to the fact that various speaker loads can cause changes to the behavior of the output power stage of the amp.
This change is most detectable with many digital amplifiers, also called Class-D amps. Class-D amplifiers employ a lowpass filter in their output to be able to reduce the switching components which are produced by the internal power FETs. Then again, the frequency response of the amp now depends upon the speaker load since the behavior of this lowpass filter is affected by the load impedance. Normally the lower the loudspeaker load impedance the lower the upper cut-off frequency of the amplifier
Generally contemporary digital or "Class-D" amps can have changes in the frequency response with different loads. The reason is the fact that Class-D amplifiers utilize switching FETs as the power phase which generate a lot of switching components. These components are eliminated with a filter that is part of the amplifier. A varying speaker load is going to impact the filter response to a point. Usually the lower the loudspeaker impedance the lower the maximum frequency of the amp. In addition, the linearity of the amplifier gain will depend on the load. Some amp topologies offer a way to compensate for changes in the amplifier gain with various loudspeaker loads. One of these approaches uses feedback. The amplifier output signal following the interior lowpass is input to the amplifier input for comparison. If not created adequately, this technique could potentially cause instability of the amplifier though. One more technique is to offer specific outputs for various loudspeaker impedances that are connected to the amplifier power stage through audio transformers.
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