Distortion to the People

Here's a direct link to a free pdf article on distortion. Very interesting read I could add.

I'm lazy so I just copy-paste the abstract here. If you're even lazier, it's about leveling, headroom, clipping and stuff.

Despite new generations of converters, higher resolution and sample rates, lower jitter, and several other technical improvements in audio production, many music lovers believe that quality on new CD releases has generally been on a downward slope since the mid 90'ies.

In previous papers [19-21], one of the contributing factors was found to be the use of extreme level ("0 dBFS+") on new albums, combined with the lack of headroom in reproduction. Clipping in production and mastering causes listening fatigue, while the sound can be additionally distorted in the digital to analog conversion at the listener. Purely digital processing, such as sample rate conversion, filtering and data reduction codecs, may exhibit the same behavior.

In Part I, this paper describes measurements to quantify the level problem, and tests performed on commercial recordings to demonstrate the phenomena. Part II is practical, and discusses quality conscious levelling and processing procedures for use in production and mastering.