Speaker Asylum

Posted by astrostar59 (A) on May 11, 2007 at 15:58:06

I have just about settled on my final tube sound system, and the last thing to improve is room acoustics.

Has anyone applied cork wall tiles or cork sheeting to their listening rooms? And what was the improvement (if any). I am thinking of adding cork to my main facing wall to the speakers, which is behind my listening position, as I believe there may be mid to high frequency reflections going on. I have marble floors (in spain) but have a large central rug and curtains.

Can I paint the cork with a thin covering of water based white paint? Will it keep the sonic benefits with the paint applied?

Thanks in advance!

• Re: cork wall treatments - middleground 14:32:23 05/12/07 (0)
  In Reply to: cork wall treatments posted by astrostar59 on May 11, 2007 at 15:58:06:

  I have had cork on the front wall of my listening room for 25 years. My mother-in-law worked for the company importing it so it was very inexpensive for me to get. I can't even remember what the room sounded like without it, so I am not much help there. What I liked was the smoky smell of the darn thing that I have always associated with hi-fi.

  The stuff I installed way back when is about an inch thick, dark brown and made up of pretty coarse pieces of cork. It came in pieces of one foot by three.

  All I can tell you is that if you can get for a good price, natural cork is a good material. You will still need some more absorptive material for other portions of the room though. I use heavy Oriental rugs on some of the walls at the front of the room.

  
  
  

  ---
• Re: cork wall treatments - Charles Hansen 12:47:49 05/12/07 (0)
  In Reply to: cork wall treatments posted by astrostar59 on May 11, 2007 at 15:58:06:

  I believe that you will have very good results with cork. Too much absorption will make your room sound "dead" and "lifeless". Cork should give just enough absorption to get rid of nasty high frequency reflections. I have found that natural materials work very well and produce a "natural" sound. I am currently using some woven rattan (dried grasses) mats on the walls with very good results. I have wanted to try cork but haven't done so yet.

  There are two kinds of cork available in the US. One is a very dark brown and has a coarser texture. It is usually sold in sheets about 1/2" thick. The other kind is light tan and much smoother. It comes in rolls and is about 1/8" thick. Both kinds would probably be useful, but I would probably start with the darker, rougher kind.

  I would try to avoid painting the cork. I think it would it would fill up the pores and negate the sonic properties.
  
  

  ---
• Re: cork wall treatments - Xanax&Coffee 23:31:00 05/11/07 (0)
  In Reply to: cork wall treatments posted by astrostar59 on May 11, 2007 at 15:58:06:

  I believe this will do more to dampen your walls than any sort of acoustic absorption. It may absorb a small amount of energy in a very narrow frequency range (probably somewhere in the mid to upper-bass regions) but I doubt if it will absorb much (if any) middle/upper-middle frequencies and almost certainly not any highs.

  I like the live end/dead end approach where you place absorptive treatments (acoustic foam, bass traps, heavy draperies, thick wall tapestries and/or decorative rugs, etc.) on the front, front corner and side walls of the room extending a bit beyond the first reflection point. You can then either use purpose made diffusers or knickknack/hobby display shelves and/or bookshelves with books spaced randomly apart on the back wall for the live/diffuse end.

  Hope this helps.
  
  
  

  ---
• Re: cork wall treatments - Godzilla. 16:31:18 05/11/07 (2)
  In Reply to: cork wall treatments posted by astrostar59 on May 11, 2007 at 15:58:06:

  http://www.zillaspeak.com/systems.asp

  A few weeks ago i added acoustic tile to my listening room walls. There was an echo when i clapped my hands sitting in the listening position.

  After the tiles were placed on the walls the echo nearly completely went away and the stereo sounded better. Not sure about painting cork but i'd imagine the cork will reduce reflections.

  BTW, when looking for reflections, sit in your listening position and place a small mirror along the sides of your room. When you can see the speaker in the reflection place a tile there. Continue going down the wall. You will see both speakers in the mirror.

  Also, put the cork or other treatment on the wall of the speakers and on the wall behind you. I may even treat the ceiling one day but things improved so much with just the walls i may leave it as is.

  Godzilla
  
  

  ---

  • Re: cork wall treatments - astrostar59 15:58:16 05/13/07 (1)
    In Reply to: Re: cork wall treatments posted by Godzilla. on May 11, 2007 at 16:31:18:

    Hey you guys! thanks for all the fab tips on cork and acoustics.

    I will do the wall application in the next couple of weeks, and add a post to let you know how it changed things.

    My room is 4.5m x 4m x 2.5m high, with a double sliding glass door to the terrace to my left,
    and an opening door into the covered terrace on the right side of the speaker wall to my front right. My cork wall is to be the one directly behind my seated position, so it should have an effect I reckon. I have marble floors on concrete, so no floor vibes, a large rug in the middle of the floor, and drapes to the terrace sliding doors. 2 sofas help as well, to beak up the reflections.

    I have a SET valve system, so I am pretty obsessed with the midrange and upper registers. My next tweak I think will be a powered sub that can fully integrate, to fill in the lower grunt.

    Thanks again for the posts!
    
    

    ---

    • Re: cork wall treatments - andyr 13:40:04 05/14/07 (0)
      In Reply to: Re: cork wall treatments posted by astrostar59 on May 13, 2007 at 15:58:16:

      I used a corkboard which I made up out of the 1" thick, 1'x3' "rougher cork" sheets, to cover about half of one side wall to stop the effect you are talking about ... "flutter echo".

      I painted it with enamel paint to be a piece of "modern art", so my wife wouldn't divorce me ... it doesn't seem to have reduced the efficacy of the echo-reduction.

      Regards,

      Andy
      
      
      
      

      ---