Where to place sound absorption panels

Discussion in 'Recording Gear and Equipment [BG]' started by slap-a-da-bass, Jul 7, 2013.

  1. slap-a-da-bass


    Sep 28, 2009

    I'm looking for advise on where to place sound absorption panels in my practice space. The intention is to reduce the reverberation in the room, and bring down volume by stoping the sound waves from bouncing around. In the picture below, the gold walls & ceiling are drywall, and the orange is block. This is in my basement, and the ceilings height is about seven and a half feet.


    I've made seven 2'x4'x 2" OC703 panels, with a 2" air gap. I've just place the panels in the room and I can tell already that there is a difference, but also I need at least double what I have. Current test areas for the panels are indicated by the blue ovals. My thought was to have a panel behind each guitar/bass amp, and one on each side of the drum kit. I want to get these panels mounted on the walls. I don't feel I have a problem with bass in the room, it's mostly echo, and low mids, though I can't confirm the freqs. I also use this room for simple multitrack recordings of my band. My computer for recording isn't shown, but on the right side of the picture, and the steps would be on the left side of the picture. The steps are very echoey.

    I'm just doing this by guessing, and am looking for some logical reason for any placement. If you have suggestions could you use a clock face for reference so I can understand where you are suggesting to place panels? I am hoping to get them hung in the next couple days.

  2. Chromer


    Nov 28, 2012
    I've been working on taming the acoustics of my mixing area recently, so I know what you're going through...

    In a room with two parallel block walls it probably doesn't much matter exactly where they are. Put in as much as you can stand to build. Play with the standoff distance from the walls. You may also want to hang a couple above the drum kit and above the amps.

    You may also want to bang up some thicker (6" ?) rockwool panels for taming low mids.

    A little furniture in the room will soak some up too. Got an old couch?

    Some diffusion couldn't hurt either, a couple curved panels would help break up standing waves between the parallel walls -- two sections on each of the long walls. They can be as simple as a bowed thin sheet of plywood with some insulation stuffed behind it to stop it from resonating.

    Finally, google "superchunk corner trap" for quick and easy (and inexpensive) bass traps.

    If you have a reasonably flat-response mic, you can use the (free!) Room EQ Wizard to check your progress and fine-tune placement. The waterfall plots are very handy for checking before/after and will give hints as to which frequencies are unbalanced, which will guide your decisions on thickness and standoff from the walls/ceiling (lower = thicker & further).

  3. seamonkey


    Aug 6, 2004
  4. D.A.R.K.

    D.A.R.K. Supporting Member

    Aug 20, 2003
    I'd start by staggering them opposite each other on the parallel surfaces throughout the room to minimize direct reflections.
    I'd also put them in, or add traps in the corners.
    Putting a couple directly over the drum kit would help too (parallel ceiling/ floor reflections).
    I need to build some more of these myself...
  5. Start with some floor carpets and bass traps in the corners. PS - the above Ethan Winer link is very good.
  6. groooooove

    groooooove Supporting Member

    Dec 17, 2008
    Long Island, NY
    with this sort of thing, achieving pretty good, or very good results, is very very easy.

    however anyone who's done it knows getting excellent or near perfect results is very very hard.

    basically, long flat surfaces are no good. do what you can to eliminate flat even surfaces. somewhat random placement of foam blocks around the room on the walls is all it takes. a little trial and error may give better and worse results.

    a friend of mine swears by putting foam blocks above the drummers cymbals, on the ceiling. (especially in small drum recording rooms.) i've heard his recordings and they do sound good, so maybe it's working. i do it too just because he said it works, but i never actually messed around much with it.

    good luck

  7. slap-a-da-bass


    Sep 28, 2009
    Thanks for the replies.

    building three superchunk bass traps was next on my list to replace the broadband panels I have now. The idea of staggering panels on opposite walls makes sense to me, so I think that's the route I'm going to go to start. As I said I will likely need double or triple what I have, but at least I have a start.

    I was also thinking about carpeting the floor, or using area rugs. Only problem is the area rugs I have are really ugly.
  8. Chromer


    Nov 28, 2012
    Carpet will really only help with high frequencies and can unbalance the room if you get silly and, say, put it on the walls... Put a couple down to have comfortable places to stand or to protect the floor, but it isn't really useful for treatment.
  9. Corey Y

    Corey Y Guest

    Jun 3, 2010
    When I set up my mixing room I ended up using mostly "BareTraps" from RealTraps.


    I'm handy, have a wood shop at my disposal and have access to a lot of materials at wholesale prices, so I priced out building my own first. The RealTraps products ended up being less with shipping than the materials cost for what I was going to do. I supplemented with one other product that was lower cost for behind my monitors and my cloud. They're good people to work with, they'll give you plenty of information on what products work best for what application, placement and that sort of thing. Their website is a good resource for that sort of information in general. Ethan Winer is one of the owners, he's already been mentioned in this thread.

    As for placement and planning, that's a whole other thing and it's in depth. I laid out my room in full scale at least a dozen times over the course of a year before I bought anything. It's kind of a hefty purchase, but it's one that's practical and makes a lot of sense if you're investing in improving mixing skill. I'd certainly advocate spending time and money putting together a well treating mixing space before upgrading monitors or other pieces of gear. Your specific application might not revolve around mixing, but I'd encourage you to look at the RealTraps site and digest all the information to start, even if you don't buy from them.
  10. A long throw in an olblique (diagonal) setup might be helpful in that room coupled with traps - and other sound absorbing materials. I bought a bunch of moving blankets CHEAP at Harbor Freight when they were on sale for a venue we do love shows/weekly jams at. The room was ALL flat drywall walls, hardwood floors, 2 story ceilings and windows. It was like playing in a racquetball court.

    Try this

    @ $6 a piece - thats hard to beat for a 72"x80" sheet
    I couldn't even by the batting for insulated drapes at that! We folded them in half for our application and used about 25 of them and some other materials. It was a world of difference. You still have to pay attention to your volume BTW.........
  11. BassinCT

    BassinCT …still tuning… Supporting Member

    Jun 17, 2006
    Connecticut, USA
    All of the suggestions so far are to be considered, particularly the idea of including diffusion in the mix (Chromer's post mentioned diffusion). The first thing I would do would be to address the things that can be done cheaply and quickly. Particularly the low ceiling and hard floor issue. The idea of using area rugs where you will be standing will make a noticeable difference there. However, it appears that you may need more than that to tame things.

    See if you can work in a combination of diffusing and absorbing materials that you can move around easily, letting your ears judge the balance and level of the reverberation before you mount anything to the walls. For my trapezoid-shaped rehearsal space at a high school, a clueless contractor hung absorption panels everywhere (bracket-mounted, fortunately) and it was unbearably dead. I spent a week removing and re-positioning in between rehearsals until it sounded right. What I ended up with was basically staggered positioning. As you experiment, please share what you come up with as a solution.
  12. Kubicki440


    Feb 6, 2011
    Nice on the Harbor Freight find, I may have to try those for my basement studio. I was thinking of these...