As many of you know through (I hope) happy experience, we work a lot with acoustics. But what does that mean? Let’s deal with some of the common misconceptions right now.
Acoustic Treatment vs Sound Insulation
Let’s get the big one out of the way first. Sound insulation is a completely different topic from acoustic treatment. The two are barely linked at all, though they share some common materials in their solutions.
When we talk about acoustic treatment, we’re normally talking about controlling the sound within a space. In our situation, this is usually for one of two reasons - either to be able to produce a better recorded sound that isn’t adversely affected by room acoustics, or to ensure that the monitoring (listening) environment is such that you can rely on the sound you hear from your loudspeakers.
Sound insulation (or soundproofing, a term we discourage), on the other hand, is put in place in order to limit the transmission of sound between areas. You might be trying to eliminate the sound of passing cars from your recordings, or to stop sharing your mix with the flat next door.
Internal room acoustics can nearly always be improved, regardless of room size and shape (though small rooms are more challenging).
Sound insulation is usually more complicated, expensive and disruptive.
Look, it just doesn’t exist. Don’t listen to anyone who tells you they can either soundproof your room or improve your room acoustics with a pot of paint. It will make no measurable difference to sound insulation and any difference to room acoustics will be tiny and unbalanced.
Stick Some Foam on the Walls
Whilst foam can be useful to some extent, it shouldn’t be over-used and it would generally need to be accompanied by some more massive materials.
Foam, particularly thin foam, will absorb sound only at relatively high frequencies. If you cover your walls in foam, you will lose the high frequency content of your sound without having any significant effect on the low frequency, resulting in an unbalanced sound.
It’s Dead ... That’s Good, Right?
Reflections and reverberation aren’t always a bad thing. Totally anechoic rooms feel very odd to most of us, and are rarely the catalyst for creative brilliance. Certainly for monitoring, a reverberation that is relatively even across the frequency spectrum, is more important than the room feeling dead. We often encounter badly treated rooms that feel ‘dead’ due to lots of treatment of high frequencies (see point 3), but in fact lower frequency resonances are still very much at large, making for a really uneven monitoring environment.
Reflection Filters Solve Everything
Reflection filters are increasingly popular tools for recording vocals in less-than-ideal rooms, and certainly do have their place; but they by no means guarantee a good vocal sound! It’s worth considering that with most cardioid microphones, the most sensitive area of the pickup pattern by far is the front ie. behind the vocalist. So if you’ve popped your singer behind a reflection filter in an empty warehouse, there’s every chance you’re going to make a recording that sounds like it was made in an empty warehouse. With this in mind, consider some absorption behind the vocalist too.