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Title: Sound dampening techniques / materials for basement (reverby) venue
Post by: Josh Billings on November 23, 2016, 09:10:40 pm
My buddy is opening a venue and it's underground in a basement with cement floors and cement walls / celings...needless to say there's some reverb to the space that isn't very pleasing.

He's looking for some low cost solutions that could help with the problem. Gotta be legit (fire retardant and whatnot). I've seen some venues with a spray on the ceilings, but not sure what it is.

From my recollection it's about 50x100 ft with maybe 8-10 ft ceilings

Josh Billings
Title: Sound dampening techniques / materials for basement (reverby) venue
Post by: Andrew Henderson on November 23, 2016, 09:50:19 pm
What's the budget? I'd start with the ceiling. It's an easy way to cover a lot of surface area to tame reflections while keeping the absorbing material out of the way. Does he have drop ceiling tiles? If not, that's something that would be really easy to pay an average contractor to do. If the ceiling is already done, move on to the walls. Owens-Corning 703 or 705 insulation is great. The more surface area he covers, the less reverb will be in the room. The thicker it is, the lower the frequency it will absorb. If he's doing it himself, he'll need to wrap it in some acoustically transparent fabric. Burlap is the easiest to find, but there are other options too. There are a lot of prefab solutions for "703 baffles" if DIY isn't preferred. You can get them with artwork or designs on them, which would probably help in deterring people from leaning on them. A big, thick, sound-absorbing curtain behind and to the sides of the stage will help and look good. Add 703 behind it for even better results.
Title: Re: Sound dampening techniques / materials for basement (reverby) venue
Post by: Randy Pence on November 24, 2016, 07:31:13 am
Spacing the mineral wool fiber from the wall allows a lower operating frequency without increased material thickness, too.
Title: Re: Sound dampening techniques / materials for basement (reverby) venue
Post by: Andrew Henderson on November 24, 2016, 08:54:52 am
Spacing the mineral wool fiber from the wall allows a lower operating frequency without increased material thickness, too.
True. You'd especially want to put them out of reach of the crowd if you did that though, because they'd likely be more susceptible to damage.
Title: Re: Sound dampening techniques / materials for basement (reverby) venue
Post by: Kevin Maxwell on November 24, 2016, 11:08:24 am
My buddy is opening a venue and it's underground in a basement with cement floors and cement walls / celings...needless to say there's some reverb to the space that isn't very pleasing.

He's looking for some low cost solutions that could help with the problem. Gotta be legit (fire retardant and whatnot). I've seen some venues with a spray on the ceilings, but not sure what it is.

From my recollection it's about 50x100 ft with maybe 8-10 ft ceilings

Josh Billings


Acoustic treatment well done can make a fantastic difference to a room. Not doing it right can make a room really sound weird. I donít know any low priced consultants only expensive ones but have been surprised at how much of a difference they can make. If you try doing it yourself I would suggest coming up with a way to temporarily place any panels on the walls so you can experiment and see how it sounds with different placement. BTW concrete that has never been painted (with anything) it much better acoustically then painted concreate. You canít un-paint it.  Donít permanently mount it till you experiment. You may find you need a lot less them you think or you might need more. But donít get carried away and make the room acoustically dead.

Be careful that you donít overdo it with absorption. You want diffusion also. There are some interesting panels that can be home made that include both absorption and diffusion. This guy who specializes in churches has some pictures on his website that shows some of his designs. http://www.jdbsound.com/work/jdb2.html

I remember reading a while ago on his website about using Sonotubes by themselves for diffusion. They are cardboard tubes that are used as a form to pour concrete in for construction. http://www.sonotube.com/sonotubeconcreteforms.aspx . You can take different diameter ones and cut them in half to make your out rounds. You can experiment with using them by making a bunch and screw a piece of wood (furring strip about 5 feet long) to it so you can prop them against the wall at a height that you might put them, and see how they work in different positions before permanently coming up with a way to finish and mount them. I think if you stuff them with fiberglass insulation and have an acoustic transparent cloth on the top it also acts as a base trap.   

I hope this gives you some ideas.
Title: Re: Sound dampening techniques / materials for basement (reverby) venue
Post by: Stephen Kirby on November 24, 2016, 03:54:10 pm
There's a small venue around there that has corrugated steel along the walls in their section of a little strip mall.  You'd think it would be horrible but the diffusion actually works well.

OC703 in a wood frame so that it's spaced an inch or two off the wall is probably the best bet for a safe and reasonable cost.  You can buy a box of it from contractor supply places.  This is what you see on the walls of cinder block movie theaters, and a few on each wall work there.

Cheaper but less effective would be dropped ceiling panels glued up on the walls in spots.

I think it's well understood, which is why nobody has mentioned it so far, but mattress foam and the like is a no no.  We don't need any more Great White tragedies. 
Title: Re: Sound dampening techniques / materials for basement (reverby) venue
Post by: Ivan Beaver on November 24, 2016, 04:25:02 pm
What's the budget? I'd start with the ceiling. It's an easy way to cover a lot of surface area to tame reflections while keeping the absorbing material out of the way. Does he have drop ceiling tiles? If not, that's something that would be really easy to pay an average contractor to do. If the ceiling is already done, move on to the walls. Owens-Corning 703 or 705 insulation is great. The more surface area he covers, the less reverb will be in the room. The thicker it is, the lower the frequency it will absorb. If he's doing it himself, he'll need to wrap it in some acoustically transparent fabric. Burlap is the easiest to find, but there are other options too. There are a lot of prefab solutions for "703 baffles" if DIY isn't preferred. You can get them with artwork or designs on them, which would probably help in deterring people from leaning on them. A big, thick, sound-absorbing curtain behind and to the sides of the stage will help and look good. Add 703 behind it for even better results.
The problem is that a fire retardant covering is often more expensive than the actual fiberglass panels.

There are to many examples of treatments that are not fire retardant killing people to consider anything else.

"Well it was cheap" is NOT what the judge wants to hear.
Title: Re: Sound dampening techniques / materials for basement (reverby) venue
Post by: Cailen Waddell on November 24, 2016, 07:45:17 pm
The problem is that a fire retardant covering is often more expensive than the actual fiberglass panels.

There are to many examples of treatments that are not fire retardant killing people to consider anything else.

"Well it was cheap" is NOT what the judge wants to hear.

This is 100% correct

Rosebrand.com has some reasonably priced IFR fabrics (inherently flame retardant) but compared to non FR fabric it is very expensive. 

I always encourage most people to buy IFR rather than treated FR.   re treatment done well is hugely expensive.


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Title: Re: Sound dampening techniques / materials for basement (reverby) venue
Post by: Rick Powell on November 25, 2016, 01:38:23 am
One of the places with the lowest cost commercially available pre-made panels is ATS Acoustics. They also sell DIY raw materials such as O-C 703 sheets, Guilford fire-rated fabrics, and other items if you want to save money and do the labor and assembly yourself. I made some 2 x 4 panels as well as some bass traps from their raw materials for my home studio that worked really well.

www.atsacoustics.com
Title: Re: Sound dampening techniques / materials for basement (reverby) venue
Post by: Randy Pence on November 25, 2016, 08:47:09 am
True. You'd especially want to put them out of reach of the crowd if you did that though, because they'd likely be more susceptible to damage.

As the crowd soaks up sound anyway, this is good acoustic advice, too.  I'm 6'2", so If I can't reach up and grab it, most others likely won't, either.

All this said, 10 years ago, I built and installed panels for a techno club featuring lots of messy afterhours parties and they are still undamaged today.  Fabric of choice was treated burlap.  The walls have gotten the occasional graffiti tagging, but the panels have oddly been left alone.