Music Machinery

Recorded music doesn’t sound as good as it used to. Recordings sound muddy, clipped and lack punch. This is due to the ‘loudness war’ that has been taking place in recording studios. To make a track stand out from the rest of the pack, recording engineers have been turning up the volume on recorded music. Louder tracks grab the listener’s attention, and in this crowded music market, attention is important.   And thus the loudness war – engineers must turn up the volume on their tracks lest the track sound wimpy when compared to all of the other loud tracks. However, there’s a downside to all this volume. Our music is compressed. The louds are louds and the softs are loud, with little difference. The result is that our music seems strained, there is little emotional range, and listening to loud all the time becomes tedious and tiring.

I’m interested in looking at the loudness for the recordings of a number of artists to see how wide-spread this loudness war really is.  To do this I used the Echo Nest remix API and a bit of Python to collect and plot loudness for  a set of recordings.   I did two experiments. First I looked at the loudness for music by some of my favorite or well known artists. Then I looked at loudness over a large collection of music.

First, lets start with a loudness plot of Dave Brubeck’s Take Five.  There’s a loudness range of -33 to about -15 dBs – a range of about 18 dBs.

Dave Brubeck - Take Five

Now take a look at a track from the new Metallica album.  Here we see a dB range of from about -3 dB to about -6 dB – for a range of about 3 dB.  The difference is rather striking. You can see the lack of dynamic range in the plot quite easily.

Metallica - Cyanide

Now you can’t really compare Dave Brubeck’s cool jazz with Metallica’s heavy metal – they are two very different kinds of music – so lets look at some others. (One caveat for all of these experiments – I don’t always know the provenance of all of my mp3s – some may be from remasters where the audio engineers may have adjusted the loudness, while some may be the original mix).

Here’s the venerable Stairway to Heaven – with a dB range of -40 dB to  about -5dB for a range of 35 dB.  That’s a whole lot of range.

Led Zeppelin - Stairway to Heaven

Compare that to the track ‘supermassive black hole’ – by Muse – with a range of just 4dB.  I like Muse, but I find their tracks to get boring quickly – perhaps this is because of the lack of dynamic range robs some of the emotional impact.  There’s no emotional arc like you can see in a song like Stairway to Heaven.

Muse - Supermassive Black Hole

Some more examples – The Clash – London Calling. Not a wide dynamic range – but still not at ear splitting volumes.

Clash - London Calling

This track by Nickleback is pushing the loudness envelope, but does have a bit of dynamic range.

Nickleback - Never Again

Compare the loudness level to the Sex Pistols.  Less volume, and less dynamic range – but that’s how punk is – all one volume.

Sex Pistols - Anarchy in the U.K.

The Stooges – Raw Power is considered to be one of the loudest albums of all time. Indeed, the loudness curve is bursting through the margins of the plot.

The Stooges - Raw Power

Here in one plot are 4 tracks overlayed – Red is Dave Brubeck, Blue is the Sex Pistols, Green is Nickleback and purple is the Stooges.

Combined plot

There been quite a bit of writing about the loudness war. The wikipedia entry is quite comprehensive, with some excellent plots showing how some recordings have had a loudness makeover when remastered.  The Rolling Stone’s article: The Death of High Fidelity gives reactions of musicians and record producers to the loudness war.  Producer Butch Vig says “Compression is a necessary evil. The artists I know want to sound competitive. You don’t want your track to sound quieter or wimpier by comparison. We’ve raised the bar and you can’t really step back.”

The loudest artists

I have analyzed the loudness of about 15K tracks from the top 1,000 or so most popular  artists.  The average loudness across all 15K tracks is about -9.5 dB.  The very loudest artists from this set – those with a loudness of -5 dB or greater are:

It is interesting to see that Avril Lavigne is louder than Metallica and Katy Perry is louder than Megadeth.

The Quietest Artists

Here are the quietest artists:

(note that I’m not including classical artists that tend to dominate the quiet side of the spectrum)

Again, there are caveats with this analysis. Many of the recordings analyzed may be remastered versions that have have had their loudness changed from the original. A proper analysis would be to repeat using recordings where the provenance is well known. There’s an excellent graphic in the wikipedia that shows the effect that remastering has had on 4 releases of a Beatles track.

Loudness as a function of Year

Here’s a plot of the loudness as a function of the year of release of a recording (the provenance caveat applies here too).  This shows how loudness has increased over the last 40 years

Loudness as a function of year

I suspect that re-releases and re-masterings are affecting the Loudness averages for years before 1995.  Another experiment is needed to sort that all out.

Loudness Histogram:

This table shows the histogram of Loudness:

Histogram of loudness

Average Loudness per genre

This table shows the average loudness as a function of genre.  No surprise here, Hip Hop and Rock is loud, while Children’s and Classical is soft:

So, why do we care? Why shouldn’t our music be at maximum loudness? This Youtube video makes it clear:

Luckily, there are enough people that care about this to affect some change. The organization Turn Me Up! is devoted to bringing dynamic range back to music.  Turn Me Up! is a non-profit music industry organization working together with a group of highly respected artists and recording professionals to give artists back the choice to release more dynamic records.

If I had a choice between a loud album and a dynamic one, I’d certainly go for the dynamic one.

Update: Andy exhorts me to make code samples available – which, of course, is a no-brainer – so here ya go:  volume.py