Talking to AI on Nostr: The dynamic range can have a significant effect on the loudness of recorded music. ...
The dynamic range can have a significant effect on the loudness of recorded music. The term loudness is used to describe the perceived level rather than the physical, mea- sured sound pressure level. A number of factors contribute to perceived loudness, such as power spectrum and crest factor (the ratio of the peak level to the RMS level). Given two musical recordings with the same peak level, the one with a smaller crest factor will generally sound louder because its RMS level is higher. When judging the loudness of sounds, our ears respond more to average levels than to peak levels.
Dynamic range compression increases the average level through a two-stage process starting with a gain reduction of the loudest or peak levels followed by a linear output gain, sometimes called makeup gain. Compression and limit- ing essentially lower only the peaks (the loudest parts) of an audio signal and then apply a linear gain stage to bring the entire audio signal back up so that the peaks are at the max- imum possible level for our recording medium (e.g., 0dB full scale [dBFS] for digital audio). The linear gain stage after compression is sometimes called makeup gain because it is making up for peak level reduction, and some compressors and limiters apply an automatic makeup gain at the output stage. The process of compression and limiting reduces the crest factor of an audio signal, and when makeup gain is applied to restore the peaks to their original level, the RMS level is increased as well, making the overall signal louder. So by reducing the crest factor through compression and limiting, it is possible to make an audio signal sound louder even if its peak level is unchanged.
It may be tempting for a novice engineer to normalize a recorded audio signal in an attempt to make it sound louder. Normalizing is a process whereby a digital audio editing pro- gram scans an audio signal, finds the highest signal level for the entire clip, calculates the difference in dB between the maximum recordable level (0dBFS) and the peak level of an audio signal, and then raises the entire audio clip by this dif- ference so that the peak level will reach 0 dBFS. Because engi- neers typically want to record audio signals so that the peak levels are as close as possible to 0dBFS, they may only get a couple of decibels of gain at best by normalizing an audio signal. This is one reason why the process of digitally normal- izing a sound file will not necessarily make a recording sound significantly louder. Engineers can, however, still make a sig- nal seem louder through the use of compression and limit- ing, even if the peaks are already hitting 0 dBFS.
In addition to learning how to identify the artifacts pro- duced by dynamic range compression, it is also important to learn how to identify static changes in gain. If the overall level of a recording is increased, it is important to be able to recognize the amount of gain change applied in decibels.
Dynamic range compression increases the average level through a two-stage process starting with a gain reduction of the loudest or peak levels followed by a linear output gain, sometimes called makeup gain. Compression and limit- ing essentially lower only the peaks (the loudest parts) of an audio signal and then apply a linear gain stage to bring the entire audio signal back up so that the peaks are at the max- imum possible level for our recording medium (e.g., 0dB full scale [dBFS] for digital audio). The linear gain stage after compression is sometimes called makeup gain because it is making up for peak level reduction, and some compressors and limiters apply an automatic makeup gain at the output stage. The process of compression and limiting reduces the crest factor of an audio signal, and when makeup gain is applied to restore the peaks to their original level, the RMS level is increased as well, making the overall signal louder. So by reducing the crest factor through compression and limiting, it is possible to make an audio signal sound louder even if its peak level is unchanged.
It may be tempting for a novice engineer to normalize a recorded audio signal in an attempt to make it sound louder. Normalizing is a process whereby a digital audio editing pro- gram scans an audio signal, finds the highest signal level for the entire clip, calculates the difference in dB between the maximum recordable level (0dBFS) and the peak level of an audio signal, and then raises the entire audio clip by this dif- ference so that the peak level will reach 0 dBFS. Because engi- neers typically want to record audio signals so that the peak levels are as close as possible to 0dBFS, they may only get a couple of decibels of gain at best by normalizing an audio signal. This is one reason why the process of digitally normal- izing a sound file will not necessarily make a recording sound significantly louder. Engineers can, however, still make a sig- nal seem louder through the use of compression and limit- ing, even if the peaks are already hitting 0 dBFS.
In addition to learning how to identify the artifacts pro- duced by dynamic range compression, it is also important to learn how to identify static changes in gain. If the overall level of a recording is increased, it is important to be able to recognize the amount of gain change applied in decibels.