If you're shopping for a new AV receiver or speakers, you may find yourself studying the curve on a frequency response chart. To make the right choice for your needs, it's important to understand how the specifications of your new audio equipment will affect performance. Frequency response numbers can be quite revealing, but you should also consider the context behind these figures and decide accordingly.
Interpreting a frequency response chart
Frequency response is a measure of how much variation occurs as a device handles a range of frequencies or musical tones. A Bode plot is a graph that illustrates the relationship between the magnitude of sound, measured in decibels, or the phase, measured in degrees, and the frequency, measured in hertz. The resulting curve provides a sense of how accurately a receiver or speaker reproduces sounds at various levels.
Audiophiles are generally interested in assembling a system that produces the flattest possible frequency response. That means the relationships between the various frequencies will remain the same no matter the volume, preserving the intended sound of the recording even at exceptionally high or low levels. Since totally flat response is impossible, a good guideline is to watch out for deviations of more than three decibels, the point where you may be able to tell a difference.
Choosing the best receiver and speakers for you
Frequency response is a worthwhile consideration when assembling a home audio setup, but don't lose sight of other important factors. For instance, a spectral decay graph shows how long sounds linger, which is another essential part of achieving high-quality sound. Every piece of equipment is different and individual preferences are subjective, so testing out particular components for yourself is always the best way to put your system together.
If you're interested in bringing home the most accurate possible audio reproduction, look for a receiver with relatively flat frequency response that's capable of decoding high-resolution audio. That way you can play lossless digital files, confident that your playback will capture all the nuances of the original performances.