Audio amp suppliers normally show the frequency response of their solutions that, sad to say, will not necessarily tell you a lot regarding the sound quality. To help you make a smarter purchasing decision, I am going to clarify what this spec means and how to understand it. This I hope is going to ensure you'll get the best amp for your project.
A large frequency response doesn't mean the amp offers good sound quality. For example an amplifier with a frequency response between 30 Hz and 15 kHz might sound a lot better than a different amplifier having a response between 10 Hz and 30 kHz. Furthermore, each maker, it seems, uses a different way of specifying the lowest and maximum frequency of their amps. The normal convention is to show the frequency range inside which the gain will drop a maximum of 3 dB from the nominal gain.
On the other hand, the frequency response quite often is used to mislead consumers by way of extending the frequency range far beyond the range where the amplifier still operates correctly and also conceals the fact that the amplifier isn't linear. If possible you ought to attempt to obtain a frequency response diagram from the producer. In this diagram, you'll find the way the amplifier functions within the frequency response range. You may also discover any peaks or valleys the amplifier could possibly have. Peaks as well as valleys can lead to colorization of the music. Preferably the amp should have a constant gain inside the whole frequency response apart from the drop off at the lower and upper limit. In addition to the frequency response, a phase response diagram will also tell a whole lot about the overall performance in addition to quality of sound of the amp. To better comprehend the frequency response behavior of a certain type, you should try to figure out under which circumstances the response was calculated. You might find this information in the data sheet of the amp. However, many suppliers are not going to publish these in which case you should make contact with the producer directly. In fact amplifiers may have different frequency responses depending on the speaker which is connected.
Mainly current digital or "Class-D" amplifiers can have changes in the frequency response with various loads. The primary reason is the fact that Class-D amps utilize switching FETs as the power stage that produce quite a lot of switching components. These components are removed using a filter that is part of the amplifier. A varying loudspeaker load is going to affect the filter response to some amount. Usually the lower the loudspeaker impedance the lower the maximum frequency of the amplifier. Furthermore, the linearity of the amplifier gain is going to depend on the load.
The frequency response of Class-D amps shows the greatest change with various speaker loads due to the built-in lowpass filter that eliminates switching noise from the amplifier's signal. However, the frequency response of the amplifier now is dependent upon the loudspeaker load considering that 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 Some amps include feedback as a way to compensate for changes in gain because of different attached loads. Yet another method is to offer dedicated outputs for different loudspeaker impedances that are attached to the amplifier power stage by using audio transformers.
A large frequency response doesn't mean the amp offers good sound quality. For example an amplifier with a frequency response between 30 Hz and 15 kHz might sound a lot better than a different amplifier having a response between 10 Hz and 30 kHz. Furthermore, each maker, it seems, uses a different way of specifying the lowest and maximum frequency of their amps. The normal convention is to show the frequency range inside which the gain will drop a maximum of 3 dB from the nominal gain.
On the other hand, the frequency response quite often is used to mislead consumers by way of extending the frequency range far beyond the range where the amplifier still operates correctly and also conceals the fact that the amplifier isn't linear. If possible you ought to attempt to obtain a frequency response diagram from the producer. In this diagram, you'll find the way the amplifier functions within the frequency response range. You may also discover any peaks or valleys the amplifier could possibly have. Peaks as well as valleys can lead to colorization of the music. Preferably the amp should have a constant gain inside the whole frequency response apart from the drop off at the lower and upper limit. In addition to the frequency response, a phase response diagram will also tell a whole lot about the overall performance in addition to quality of sound of the amp. To better comprehend the frequency response behavior of a certain type, you should try to figure out under which circumstances the response was calculated. You might find this information in the data sheet of the amp. However, many suppliers are not going to publish these in which case you should make contact with the producer directly. In fact amplifiers may have different frequency responses depending on the speaker which is connected.
Mainly current digital or "Class-D" amplifiers can have changes in the frequency response with various loads. The primary reason is the fact that Class-D amps utilize switching FETs as the power stage that produce quite a lot of switching components. These components are removed using a filter that is part of the amplifier. A varying loudspeaker load is going to affect the filter response to some amount. Usually the lower the loudspeaker impedance the lower the maximum frequency of the amplifier. Furthermore, the linearity of the amplifier gain is going to depend on the load.
The frequency response of Class-D amps shows the greatest change with various speaker loads due to the built-in lowpass filter that eliminates switching noise from the amplifier's signal. However, the frequency response of the amplifier now is dependent upon the loudspeaker load considering that 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 Some amps include feedback as a way to compensate for changes in gain because of different attached loads. Yet another method is to offer dedicated outputs for different loudspeaker impedances that are attached to the amplifier power stage by using audio transformers.
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