Originally posted December 30, 2010
Have you ever noticed the volume difference between a current recording and one from 25 or so years ago? It becomes very obvious if you were to play them back to back. Current pop recordings tend to be “in your face” while older recordings have far more dynamic range. So why is this and how is it affecting the quality of recorded music?
To understand what I’m getting at I will have to first give a brief description of audio compression. I’m not talking about digital data compression here (that is, however, worthy of discussing – but for another time), but analog compression that dates back several decades – long before the invention of the CD and mp3 technology. And for the audio engineers out there, I apologize for the lack of proper technical terminology.
When recording a sound, there is a limit to how loud or “hot” the input signal or source can be. If it’s too much, the recording becomes distorted. So essentially the volume of a recording is limited to the volume of the loudest part. For example, if you were recording a song where most of it was fairly quiet, but then had a passage that was very loud, you are essentially limited to keeping the input at a level relative to the louder section. If you had the input higher in order to get the quieter parts stronger, the louder passage would cause distortion when recorded.
A brilliant solution to the problem was the invention of audio level compression, also known as dynamic range compression. Essentially what happens is that the compressor squeezes down the “peaks” in the volume. As a result, the dynamic range is decreased (the difference between the loudest and quietest parts). Consequently, the overall volume level can be raised before distortion will occur. The more the peaks are squeezed down (compressed), the more the overall level can be increased. Even though compression works by squeezing down the peaks and making them quieter, the general effect is a perceived increase in the overall volume.
From a music producer or audio engineer’s point of view, this is an excellent tool. It can be used very effectively to “smooth” out a recording, enabling a much better and consistent mix to be created. For example, if a bass guitar player perhaps played a few notes too quietly, but otherwise played the perfect “take,” compression can be used to “smooth” it out rather than re-doing the take. Essentially, by “squeezing” the louder notes down, the quieter ones seem louder, thus creating a much smoother and consistent sounding recording. Compression works great on recording vocals for the same reason – to smooth the track out and make it easier to mix. Cymbals also sound great with compression, as the decay of a cymbal crash can be drawn out to increase the length of the trail – a nice effect. And not only is compression used on individual tracks of a recording, but is also used on the final overall mix (mastering) to help smooth out the overall sound.
So what’s the problem then? Well, as always seems to be the case, great tools eventually get used for the wrong reason. In the 1960s, competition was fierce between radio stations on the AM band. Each station wanted to “stand out” as a listener tuned the radio dial. Compression was used in the studio to keep the “peaks” down in order to increase the overall volume. Once one station did it, they all had to do it simply to keep up. A tell-tale sign that lots of compression is being used is if the breaths of a speaker or singer are way out of proportion (much louder than normal). TV commercials are notorious for this – I’m sure you’ve noticed how loud and “in your face” they can sound during a break in a movie.
But as time has gone on, compression has been used more and more in the music recording studio, and then is compounded on the airwaves by the radio and television stations that apply their own compression. As a result, everything tends to sound “in your face.”
So back to the music and the problem. What the overuse of compression has essentially done over the last few decades is to dramatically decrease the dynamic range in the vast majority of music recordings. Essentially everything is loud – even the “quiet” parts. This certainly has some very practical applications where you may not want sudden or unexpected volume spikes, or the quiet parts to be too quiet – listening to music in your car for example. But the problem is much like the original competition on the AM radio dial – once one does it, everyone has to do it to be heard. And as a negative consequence, most current recordings, especially in commercial pop music (in all genres), have virtually no dynamic range. The ears of listeners over the years have been systematically desensitized. Below is an example to show the increase of overall volume over the years. This is an excerpt from the Beatles song “Something,” as remastered several times over the years. Each time the track gets louder in order to blend in better with the current “sound” on contemporary recordings. Up to the 1993 master, all that’s happened is that the volume has increased – no big deal really. But the problem happens with the 2000 release. You’ll notice that in order to prevent distortion, the highest peaks need to be compressed, allowing the quieter parts to be raised in volume. But as a result, the dynamic range is decreased. In other words, the musical expressiveness of the original recording has been compromised.
Unfortunately many people now, especially younger ones, who have been constantly bombarded by highly compressed pop music have very little patience for expressive music that takes advantage of a broad dynamic range. I believe that is one of the many factors responsible for the decline of appreciation for classical and orchestral music. It simply isn’t “in your face” enough and requires focused listening.Classical recordings do indeed use compression, as well as radio stations that broadcast classical music, but not even remotely close to the same degree as pop music does. Anyone with children will likely have noticed the same concept being applied visually on kids’ and youth television shows and movies – bright colors, very short fast-paced scenes, and ever-present screaming and yelling - an overstimulating assault on our senses.
But I have to admit that as a producer I also use it a lot. I simply need to in order to get the songs I produce on the radio. When I’ve had some of my previous recordings mastered for radio broadcast, I’ve asked the mastering engineer to use a good dose of compression – to get that “in your face” commercial sound. Guilty as charged. It doesn’t mean that I like it – I simply need my music to blend in with the current sound. In fact, we can get so used to the current “loud and in your face” sound that when we hear an older recording we sometimes think that something is wrong. It takes a few minutes to “re-sensitize” our ears to a broader dynamic range. And it often requires a quieter listening environment, more patience, and more focused listening to appreciate the subtle nuances of a quality recording with a broad dynamic range.
But once we are in the zone, it’s like a breath of fresh sonic air.