Why do some CDs appear to play louder than others?

Asked by: Steevo Barker, Stevenage

CDs have a wide dynamic range. In other words, there's a big difference between the quietest and loudest sounds they can reproduce. In some cases, the music might not be mastered to use all the dynamic range. But more modern recordings use technology to optimise how much audio energy can be squeezed into the available dynamic range. The resulting music sounds punchier and brighter, making it seem louder.

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