Your Acoustics are Psycho!

Part 1 in The Podcast Audio Series


The room you choose to record your Podcast is as important, if not more so, as the equipment used. A well balanced room, acoustically speaking, can save a lot of headache depending on the potential for acoustical problems. So now let’s pick out our room. The first thing we have to do is pick one that is optimal for recording audio. Comfort is a plus. A decent temperature is paramount so you don’t have to open windows, doors, turn on fans, etc. And it should be the quietest as well. If you can cut down background noise, it will only help for a better sound quality in the long run. It should be the most isolated from the outside world as far as noise is concerned. But there is one myth I must dispel. The first thing people think they need to buy in order to stop sound from passing through wall is foam. Egg crate foam, mattress foam, carpet foam, you name it, they think it will stop sound. That is absolutely, unequivocally incorrect. The only thing that will stop sound is construction. The walls have to be designed a certain way and built with certain types of material in order to be “sound proof”. So let’s just assume that construction is not possible, and we have to work with what we’ve got.

In order to tame the beast, we must first understand it. Sound is notorious for bouncing off of things. When it strikes a surface, it is partially absorbed. However, the rest will pass through or bounce back. And hard, non porous surfaces, such as walls, desks, book shelves, and other types of furniture, are your worst enemies when it comes to recording audio. Think that corner desk where you record your Podcast is a great space saver? Think again. If you are facing the corner in your room, and have untreated walls, all sorts of evil things can happen when recording your Podcast. First, sound, such as your voice, is bouncing off that wall and back into your mic. Second, if there is any noise caused by your computer fan and it is near that same corner, it is bouncing into the mic as well. You could lessen the need for a noise reduction regiment if you plan where you place your rig in the room. Of course, if you have large speakers or monitors, they will bounce as well unless you monitor with headphones.

Absorption, Diffusion, and Bass. Oh My!

So we’ve found the quietest room and we want to face that corner desk towards the corner. What’s next? Let’s start with absorption, the retention of sound without reflection or transmission. This can be helped by putting acoustical foam in problem areas. Large flat surfaces like walls and ceilings. Now covering the whole entire room is not necessary, in fact, it is downright ridiculous. A good example of foam placement can be found in the included picture in this post. Notice how foam can not only serve a function, but also become somewhat part of the décor. Yes, alternatives like egg crate foam and carpet foam could be used, but they don’t have near the absorptive properties of acoustical foam tiles. The investment is not that great either.

Diffusion basically keeps audio from congregating in one area. When diffusing a room, you can actually enhance its audio properties by widening the stereo field, making for a more effective “sweet spot”. It enhances your ability to properly mix your audio, especially when dealing with music. Proper sound diffusion can actually make a room optimal for both recording and monitoring.

Bass can be quite a burden to bear as well. It is, in fact, the hardest property of audio to control, mostly due to the fact that it is omnidirectional. So how do you control something that is all around you? Bass traps of course. Bass traps go in corners where bass tends to congregate and reflect the most. An effective bass trap placement strategy can also be seen in the photo above.

Again, just like the foam tiles, the diffusers and bass traps do not have to be in every nook and cranny of a room. An acoustical consultant can help out with a simple diagram of your room. My favorite guys that I used to frequent in my studio days, are the folks at Auralex. No, I’m not getting paid to say that. I recommend them, because their consulting service is free., But you can choose whomever you like to help you with your room problems. Why do I suggest a consultant? Because every room is different. From the shape of the walls, the distance the speakers are from you, to the type of furniture that is surrounding you. Even different types of flooring. The effects on room sound are different with carpet, tile, wood, and linoleum.

So how much is all this going to cost you? Well, that all depends on the room you choose. With a few carefully chosen items, you can at least improve the room a little. There are ready made kits as well. But what if I don’t want to cover my walls with foam and adhesive? My spouse would kill me for doing that, and I’m already in the doghouse half the month because of the extra time I invest in podcasting. There is a solution to that too. You could actually glue the needed pieces of foam, bass traps, etc, to large cardboard or some type of wood, and construct a sort of makeshift cubicle out of it. It could be torn down and put up in minutes, and again, the expense is not as much as you think. In fact, there are ready made kits for that as well, which is especially good if you don’t have the time or talent to construct them yourself.

Of course, all this is not absolutely necessary. Your Podcast isn’t going to fail because of a little wall reflection or room noise. But if you appreciate good quality audio like I do, and your room makes your recordings more difficult to control, then maybe you’d like to give it a shot. All it can do is help for a more enjoyable recording experience, and even more so, a better listening experience.

The next article entitled “The Well Equipped Podcast Rig, and the Podcasters Who Love Them” will be next.

Stay tuned!  ¶ 8:26 PM