Room Treaments - Where To Begin...

Room treatment needs to address three main items:

1. Bass reverberation time
2. First reflections
3. Slap echo

For (1), large bass traps in corners. For (2), absorptive panels at sidewalls and ceiling first-reflection points. For (3), provide absorption/diffusion on parallel surfaces until a walking-around clap test doesn't result in any pinging. The thicker panels you use for (2) and (3), the more they will help with (1).

In general, avoid panels that are purely absorptive, as they tend to unbalance the room, absorbing HF more than LF. Panels like the GIK Alpha, RPG BAD, or most products from ASC incorporate some sound scattering and will control excess reflections without over-deadening.

GIK and ASC give consultations -- last time I looked, it was for a small refundable fee. It's worth it. I found it useful to get two opinions, then decide myself how to proceed. Expect it may need some experimentation.

Another great resource is the series of YouTube videos by Jesco. They are aimed at mastering and recording engineers, but there is much that the home audiophile can take from them.

+3 GIK

It is more difficult to correct what you haven't yet measured/heard.

It is more difficult to correct what you haven’t yet measured/heard.

Now we’re getting somewhere. You can read all you want, it is of no use until and unless you learn to hear what they’re talking about. Fortunately this is super easy.

Clap your hands. Might seem silly but the lowly hand clap produces a wide range of frequencies from a point source making it ideal for learning about acoustics. So one clap, and listen. Pay attention to the way the clap itself sounds, the first echo reflection, and how the sound trails off.

If it is a thud with no reverb your room is dead and acoustic panels will only make it worse. If there is a sharp echo or ringing sound this is flutter echo you will want to break it up with diffusion panels. If there is no door and opens to a lively room you will have a long decay to deal with.

Now move around. Clap/listen/move, Stand at one side of the room and clap, repeat from the other. Won’t take long, minute or two, you will have mapped out your room and in a way you will actually understand because you have heard it.

Then get a sheet of Owens Corning 703 acoustic panel at the hardware store. Repeat your hand clapping only this time moving the panel around to different places.

It is easy to pay someone like GIK a lot of money to tell you what to do. Here’s how that goes. Mike Lavigne has by far the best room with the best acoustics I ever seen. Mike paid a bundle for the very best professional acoustic design. That’s not why his room is so great. Mike then put in the time to listen and figure out what is really going on and correct the room correction.

There really is no substitute for listening.

15 years ago, the realtor had a funny look on his face when I was walking around the new house, with furnishings, and occasionally clapped my hands or even whistled. Before the wife moved in, I was able to try out a few arrangements for speaker placement and a listening position as well. Paid off as good as it could given the circumstances. 

 Now days, when she leaves for work, I can adjust the furnishings in the room to better suit the result.