When your loudspeakers fart, are they trying to tell you something?
One of the golden rules of monitoring is to listen to your mix the way your listeners will hear it. If you don't know what they are going to experience, how can you judge whether your mix is good?
The trouble is that people listen on all kinds of systems. Mostly on cheap hifi sets, but also on personal stereos, portable stereos, in the car... the list goes on all the way up to high-end hifi.
And of course if your work is good, you might even hear it on TV or in the movie theater.
So how can you be sure that your mix will stand up on all of those systems?
Let's consider just the bottom end of the mix - the low frequency part of the audio spectrum.
It is a fact that most people listen on moving coil loudspeakers. Almost universally, the drive unit is mounted in a wooden (particle board) or plastic cabinet. The drive unit itself will have a resonant frequency at which it will vibrate strongly in response to any energy input. Nearly always the cabinet will increase this effect.
So whatever energy goes into the loudspeaker, it tends to make it vibrate at a certain frequency.
Now in high-end loudspeakers, this resonance is controlled ('damped') so effectively that it is hardly noticeable. Just what you would want in your studio monitors?
Well yes, it is important that your monitors have a well controlled low end so that they tell you exactly what is on your recording rather than telling their own story.
But such a loudspeaker will lull you into a false sense of security. You will pile on the bass until your mix sounds good and heavy. It will sound great on your high-end monitors...
But on anything else the speakers will boom like crazy. Possible fart too (I can't think of a better technical term in this context). I'm sure you have experienced loudspeaker flatulence syndrome many times and know well what it sounds like.
So the ideal pair of monitors is one that has a controlled bass, but will fart when you apply too much low end to your mix. That way, you will know that your mix won't embarrass your listener's loudspeakers.
It sounds strange to say it, but the requirements for high-fidelity loudspeakers and studio monitors are totally different. Hifi speakers should be totally accurate and produce massive amounts of bass with ease. Studio monitors should also be accurate, but they should tell you when enough bass is enough, and also tell you when you've gone too far.