You're listening to 20,000 Hertz. I'm Dallas Taylor. And this is part two of the story of mastering.

In the last episode, we looked at the history of mastering. Up until the 80s, the constraints of

analog equipment meant that music had to be mastered on the quieter side. While this may sound like a bad thing, the upside is that music from this era has really strong dynamics, almost across the board.

Pick nearly any song from the 70s or older, and you'll find a striking contrast between the quietest parts and the loudest parts.

This gives music a much more spacious and vibrant quality.

But once digital technology took over, things changed pretty quickly.

New audio technology allowed mastering engineers to make songs much louder.

Artists also started trying to one-up each other with how loud their songs were,

and music overall got louder and louder.

But all of this volume came at a price,

and music became so compressed that it lost a lot of that impact and depth. The loudness

war had begun. For some people in the industry, even music that was pushed right up to the

limit wasn't quite loud enough.

But if you've already compressed a song as much as possible, what happens when you try to make it even louder?

Beyond that, you can actually start to get distortion, where if you just push the loudness up so that it hits that digital ceiling,

where the tops of the waveforms, the musical

waveforms are literally sliced straight off. You get an effect called clipping. That sounds distorted.

That's Ian Shepard, a professional mastering engineer who also hosts a podcast called The Mastering Show.

When you clip, you literally are inserting a little blip of noise.

And that's Greg Milner.

Greg writes about music and technology and wrote a book called Perfecting Sound Forever,

an oral history of recorded music.

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