Power amplifier providers frequently publish the frequency response of their items which, sadly, will not necessarily tell you a lot concerning the audio quality. I am going to explain the meaning of this expression and also offer a few recommendations on how to interpret it while looking for an amplifier.
Commonly a lower and upper frequency are listed, for example 20 Hz – 20 kHz. This specification shows that the amp has the capacity to amplify audio inside that frequency range. You could think the larger the frequency response the better the amplifier. You should go through the specs more carefully in order to adequately understand these.
A large frequency response doesn’t mean the amplifier offers excellent sound quality. By way of example an amp having a frequency response between 30 Hz and 15 kHz might sound better than another amplifier having a response between 10 Hz and 30 kHz. Consequently it is best to have a complete frequency response graph. In order to better understand the frequency response behavior of a specific type, you should make an effort to find out under which conditions the response was determined. You may find this information in the data sheet of the amp. The fact is that numerous amplifiers will work differently with different speaker loads. This is due to the fact that different loudspeaker loads will result in changes to the behavior of the output power stage of the amplifier.
A number of audio amps include feedback to compensate for changes in gain resulting from different connected loads.