November / December 2013
In This Issue...
Why Does Your Voice Sound Strange?
Editorial By Greg Borrowman

 

  Most people these days can recognise their own voice when it's played back to them from some recording medium because they've grown up listening to that voice on phone messages and video recordings. So it's difficult to believe that there was a time when no-one knew what they sounded like, because although audio recording has been around for more than a century, few 'ordinary' people had access to sound recorders.

I can vividly remember the first time I heard my own voice played back. 'Sandy' Stevenson, a family friend, had purchased an open-reel recorder and, during a weekend visit, demonstrated it to everyone in my family. I can't remember my exact age at the time, but I do remember denying that the voice I heard was my own, despite easily identifying the voices of my parents and my brother, which he'd recorded at exactly the same time.

Why did I not recognise my own voice? Because as everyone now knows, your voice sounds completely different when you hear it played back, compared to what you hear in 'real time' when you sing or speak. Most people complain that their voice is higher-pitched and more 'nasal', whilst others complain that their accent sounds stronger on a recording than when they're listening to themselves make that recording.

The reason your voice sounds different because it is different. I like the explanation Ben Hornsby, a professor of audiology at Vanderbilt University gave to Popular Science magazine. 'When you speak, the vocal folds in your throat vibrate, which causes your skin, skull and oral cavities to also vibrate, and we perceive this as sound,' he explained. 'The vibrations mix with the sound waves travelling from your mouth to your eardrum, giving your voice a quality — generally a deeper, more dignified sound — that no one else hears. When you listen through a loudspeaker or recording device, you pick up sound only through air conduction, so the sound we're used to hearing has a lower frequency from t bone vibrations, and we like that because it sounds rich and full.'

Microphones have a lot to answer for when it comes to perceived sound quality as well. First, there's what's called the 'proximity effect' which means that the closer you are to a dynamic microphone, the more your voice will sound full and rich in the bass. Shure made a fortune by exploiting this effect with its SM series microphones. Then there's the fact that modern sound reinforcement systems mean that some men appear to be able to sing at really low frequencies, but when you take the micro- phone away, you find they cannot sustain these low frequencies at the higher volume levels required if they were to sing with an unaided voice. I was reminded of this at a recent Tripod concert, which added performer Eddie Perfect to this established a capella trio. EP was using the microphone and his throat to produce incredibly low bass notes. It sounded truly impressive, but in fact was just a vocal 'trick' made possible by modern technology.

Sometimes, hi-fi retailers use similar 'tricks' to enhance the sound of their demo speakers… though they're not doing it on purpose, they will have just learned from experience that certain speakers sound better in certain positions in their demonstration room. Just as your voice will always sound better when you're singing in a bathroom, some listening rooms will favour certain bands of frequencies over others, depending on where the speaker are positioned. So if you place speakers that are being demonstrated in this spot and use music with lots of energy in those bands of frequencies that are being reinforced by the room, the speakers will sound different (usually 'warmer', and 'richer') than they would if they'd been positioned somewhere else in the same room… or perhaps when positioned incorrectly in your own listening room.

 

--- Greg Borrowman