Loudness War

It feels great when the blog is back to normal. Sorry for the delay on various issues. Things should be catch up from now on.

We had a very successful first “Professional & HiFi Audio Course”. Thank you for all attendants, and sponsorships. We look forward to setup the second one focusing on “Computer Audio” next round.

During the course, the “loudness war” section draws large attention from everyone.

In general digital recording theory, the highest peak level is 0dBFS. Digital “OVER” can cause high distortion. During early 90’s, digital limiters are introduced to the market. These powerful digital limiters can prevents recording going over 0dBFS with its very high ratio (1000:1) dynamic control. Without the worry of digital over, engineer can bring up the recording loudness and make fully usage of digital storage. This is important for 16bit CD because if your recording is peak at -6dBFS, you are using only 15bit resolution. That was the time when digital limiters called “Maximizer”.

Later on people start notify that once you have the digital limiter in the end of the chain, you can push up the recording loudness without fear of over. The peak level will be pushed down and you lose some transients and dynamic range. The loudness war is started. Music are squeezed badly in return of loudness, but all records A&R, producers, artists and records company bosses want their ablum to sound louder. This hurts the whole industry because the squeezed dynamic are nearly impossible to recover. Plus the digital limiter artifacts are added on the recording. Further more, the change of listening habit from home stereo to iPod and Car Audio even push this loudness war to madness. Less and less people spent their quiet time listening music at home with good stereo system, audio quality becomes an non-issue. Highly squeezed music are not for long term listening because the lack of dynamic range, you will easily get bored.

The recent cases are many engineers found digital limiters produce bad artifacts when you push the level too much. They found just plainly push the level without digital limiter to let level goes digital over, reproduce better sound quality. You can easily see how bad status we are.

Metallica’s 2008 latest album Death Magnetic case was reported by Time magazine. The album was highly compressed without any kind of dynamic. It is heavily distorted and digitally clipped. However ,the original pre-limited content are used on Sony Playstation 3 game “Guitar Hero”. Metallica fans love PS3 version much more and draw hugh attention about loudness war.

More information: http://en.wikipedia.org/wiki/Loudness_war