The Complexity of Listening

Our blog articles primarily cover audio production technology and techniques, but for this article we’re going to turn the attention from hardware and software to the “human-ware”. We will explore how we listen, and how we can better understand what we hear.

Listening is of course the endgame of music production. However, before our work reaches our listeners’ ears, we obviously have to make value judgments about it ourselves, both during the creative process and when we believe it’s complete. So, can we learn to make those judgments more effectively through understanding the mechanics of listening, or do we simply have to rely on pure, in-the-moment, instinct?

The answer to that question is, “both” (surprise!). It would be absurd to argue that following our instincts in creative decision making is somehow inappropriate because music is very deeply hard-wired within our conscious (and unconscious) experience. Acting on an instinctive response to it is perfectly justified. However, we can also learn to listen more analytically and understand our instincts, so that our creative decisions are informed and optimized with a little more objectivity. But how does that play-out in our day-to-day studio work? How do we learn to listen more analytically and put that learning into practice? There are perhaps three strands in an answer to that question.

1. Understanding

In a previous blog article about 11 Tips For A Better Studio Experience, we wrote that it’s good practice never to use a plugin unless we genuinely understand what it’s doing to your material. Sometimes, however, such understanding is pretty hard to establish from a plugin’s written technical description. So, as an alternative approach, why not create a test session that contains just a minute or so of simply recorded human voice (a familiar voice is best, maybe a close friend or a family member), and apply the plugin to that?

You’ll soon then begin to appreciate what the plugin does to the audio as you adjust its settings, and you’ll be more able to predict what it is likely to do in the context of an actual mix and whether it’s worthwhile. And never mind obscure plugins, we can also use the same principle of a human voice test session to improve our understanding of, say, compression, reverb and EQ. Our hearing has evolved to be particularly sensitive to the human voice, so using that sensitivity to learn about the effects of audio processing is a neat short-cut to better understanding.

Alternatively, apps like SoundGym can also offer a fun gamified way to train your ears to notice subtle differences in audio material. With a deeper understanding of what compression, EQ, reverb, and that obscure plugin, actually do to the sound, we stand a much better chance of deploying them effectively when it really matters.

2. Inspiration

The phrase “standing on the shoulders of giants” is most often attributed to the 17th Century mathematician and physicist Sir Isaac Newton. He used the phrase not just to express admiration for the scientists who came before him, but to emphasize that his insights into the world of physics were only possible thanks to the principles his predecessors uncovered.

There are numerous giants in the history of music production and there’s absolutely nothing wrong with “standing on their shoulders”, by which we mean listening to their work to analyze and appreciate how particular songs were constructed, recorded and mixed, and then to incorporate that knowledge in our work. Such borrowing and inspiration is, after all, fundamental to how all art develops.

It’s important however that we don’t just listen in a creative bubble of our own particular musical taste. If, say, EDM is your thing, then don’t solely listen to that genre. Maybe listen also to some 1980s pop, some 1960s jazz, or some early classical, or any other genre that plays by rules unfamiliar to you. There are opportunities to create new music living in the gaps between genres, and through cross-pollination between them; borrowing and transforming ideas from elsewhere. Standing on the shoulders of giants enables us to see things that are far away, so we can use the view to take inspiration from music that lives on distant shores.

3. Appreciation

In the world of audiophiles and hi-fi, the concept of the “golden-eared” listener has been around for almost as long as audio technology itself. Those anointed with golden ears are most often influential journalists or manufacturer technical directors or consultants, and although it’s true that human hearing varies in acuity, and that experienced listeners can become highly attuned to audio details, the idea that a golden eared listener provides an immutable, flawless reference is, well, hooey.

One of the first things that any research into psychoacoustics will reveal is that our hearing is adaptive. In fact, we don’t need to research psychoacoustics to know this because we’ve probably all experienced our hearing adapting to circumstances. Loud gigs and clubs are a perfect example. For the first five or ten minutes we worry the music is too loud and that we’ll have to leave, and then miraculously, a little white later it feels actually ok. This isn’t because the FOH sound engineer has spotted our distress and turned the volume down, it’s because our brain has turned its internal gain down (the muscles around our eardrums actually tighten to reduce sensitivity – we’re all effectively fitted with a compressor. However, that isn’t to say you shouldn’t protect your ears.).

So, our hearing is adaptive in terms of overall volume, but it also displays level dependent EQ. At low volume levels our hearing is significantly less sensitive to low and high frequencies than it is at higher volume levels. This phenomenon is typically formalized in what’s known as the Fletcher-Munson curves, named after researchers Harvey Fletcher and Wilden A. Munson, who first described it in 1933. Fletcher and Munson’s “equal loudness” curves have been revised over the decades as experimental techniques have improved. These curves show the audio levels at different frequencies that are perceived to be equally loud at different overall loudness levels.

The upshot is that at an overall level of say, 90 dB, the loudness of a signal at 100 Hz is typically perceived to be around 6 dB quieter than one at 1 kHz. At an overall level of 50 dB however that difference approaches 15 dB (at first glance the Fletcher-Munson curves might look upside down, but remember they show the level required to sound equally loud, so that level at midrange frequencies is lower). The practical implication of Fletcher-Munson when we’re working on a mix at our DAW is that the broadband tonal balance we perceive will depend on how loud we play the music. But if we add our ear’s adaptive nature with regard to overall level, the situation becomes even more complex.

We actually wrote about the equal loudness curve phenomenon in a previous article: The Importance of Listening Levels. In that article we described the importance of having a reference listening level when working on a mix. Doing so helps minimize two of the major ear/brain variables: level dependent balance and adaptive volume perception.

The equal loudness effect and volume level adaptation are just two of the psychoacoustic phenomena our ears and brains demonstrate that have significance to music production, but they are two among numerous others that it’s useful to at least be conscious of.

Summary

We’ve covered a lot of ground in this article, but it can perhaps be summarized in three principles that may well help us produce better music:

1. We should improve our understanding of how signal processing, such as compression and equalization for example, works and how it influences what our listeners hear.
2. We can learn, “on the shoulders of giants” by listening analytically to the work of other recording engineers and artists, especially those in unfamiliar genres.
3. We can educate ourselves in the field of psycho-acoustics better to understand how our creative decisions might affect what our listeners experience.

More on this topic

• Wikipedia has a useful resource of psycho-acoustic phenomena presented in the form of audio “illusions”.
• Diana Deutsch, Emeritus Professor in the Psychology Department at the University of California, San Diego, has published widely on the psychology of hearing, and in particular, on audio and musical “illusions”. This video is a good place to start appreciating her work, and the immense complexity of human hearing.
• And finally, this series of videos by Casey Connor demonstrating a wide variety of psycho-acoustic phenomena is highly recommended.