Room Acoustics - Better/Faster/Cheaper

[midKnight]

Hey Everyone,

I'm just getting started on thinking about doing some treatment to my studio since I now have the desk done, and have done a ton of reading up on this subject, and it seems like I have two main paths.

Go buy pre-built traps - easy, but expensive, or build my own.

The build your own route seems to be quite popular, however after the experience of the desk, I'm not so sure I'm ready to go experience that kind of pain anytime soon again, and not to mention the build it yourself method involves cutting some semi-hazardous (in terms of breathing stuff) materials, so I wanted to get your opinions on a site I found that sells pre-built traps at what looks to be a very good price.

2'x48"x2"'s are $45 a piece, and i'd be hardpressed to build my own much cheaper than that (maybe a little, but the injuries I'd sustain really aren't worth it)...

ATS Acoustic Panels

Can anyone see any reason why I wouldn't want to get traps from this company?

Also, I'd really love to hear if any of you have come up with any really inexpensive highly inventive Macguyver type solutions to traps, as I'm sure you guys have probably done some stuff I've never thought of.

-Nick

[brandondrury]

2'x48"x2"'s are $45 a piece, and i'd be hardpressed to build my own much cheaper than that (maybe a little, but the injuries I'd sustain really aren't worth it)...

I don't think these are bass traps. They look (and cost) like broad band absorbers. I'd bet they are simply Owens Corning 703 wrapped in fabric. Good luck getting this to do anything for the low end in your room.

It's my understanding that without some kind of other design to convert the vibrations into friction, you need your insulation to be at least as thick as half the wave length. I can't vouch for if this is true or not, but I personally believe it is. If that's the case, the deepest frequency you'd be able to absorb would have a 4" wavelength.... based on my math that is 330Hz.

-----

Back in 2005, I bought $500 worth of wood and $1,000 worth of Rockwool. I built 30+ bass Helmholt Resonators and had about 25 packages of Rockwool left. I ended up spending 60 hours of work buiding the damn things. Ultimately, I think I screwed the design up. If I could go back, I would DEFINITELY just ordered Ethan Whiner's Real Traps and called it a day.

Brandon

[midKnight]

Doesn't one want a mixture of broadband absorbers and also bass traps?

I would love to just buy Ethan's stuff, but it's ungodly expensive.

-Nick

[brandondrury]

Doesn't one want a mixture of broadband absorbers and also bass traps?

That depends. The general rule is you can't have too much bass trapping. It's physically impossible. If you could actually TOTALLY absorb the low end so that zero energy was reflected back in the room, you wouldn't be happier.

The broadband stuff is entirely dependent on what's going on in the room. Some rooms won't need too much. I'd simply put it on spots of direct reflections and be done with it. You can use too much broadband absorption. When in doubt, use less.

Solving broadband-type problems are straight forward. If budget is a issue, blankets and a few t-shirts can get you by (although they won't absorb much in the low mids). Trying to absorb an 80Hz wave is a totally different animal. It's a zillion times more critical and a trillion times harder to stop.

I would love to just buy Ethan's stuff, but it's ungodly expensive.

I don't remember it being super cheap, but I didn't think it was that bad when I came close to buying it a few years ago. It depends on your situation, obviously. Dumping $3k in acoustic treatment is madness to some. To others it's only a start.

Brandon

[midKnight]

Originally Posted by brandondrury

That depends. The general rule is you can't have too much bass trapping. It's physically impossible. If you could actually TOTALLY absorb the low end so that zero energy was reflected back in the room, you wouldn't be happier.

Well that's good to know....

Originally Posted by brandondrury

I don't remember it being super cheap, but I didn't think it was that bad when I came close to buying it a few years ago. It depends on your situation, obviously. Dumping $3k in acoustic treatment is madness to some. To others it's only a start.
Brandon

Well since I'm doing this for my own amusement, yeah, spending 3k on acoustic treatment tips the scales closer to madness than reason. However I remember you saying you spent 60 hours building your own. That's a time investment I don't want to do either, so I think i'm going to have to aim for somewhere in the middle.

So the hunt for cheap pre-made bass traps begins.

Out of curiousity, have you ever used any of the software programs out there like EFT5 or Room EQ Wizard to figure out what your particular room needs are, and if so, do you like either of them?

(I have the demo version of EFT5 and Room EQ wizard is freeware), but both seem difficult for a novice like myself...

[valpurgisnite]

I recently came upon a suggestion for a bass trap.

What you will need per bass trap:
1 concrete form (tube) 10" in diameter
1 compass (Think geometry)
1 3/4" plywood (12"x24")
1 1" board (birch or oak should be fine) (16"x24")
Fabric (carpet to match your room preferably)
wood stain of your choice (for visual appeal)
1 can of spray adesive
Sand

Directions:
Draw 2 circles on the plywood the same diameter as the inner part of the tube. Make sure you measured correctly because these will keep the sand from getting all over the place. Take one of the disks and coat the side with glue. Carefully push it into the concrete form so it is flush. For additional securing purposes, screw in 3 screws at equal intervals into the side of the form so they line up and screw into the disk also.

Use the fabric to cover the complete outside of the tube and the adhesive to secure it. Make sure to leave some overhang so it can be tucked into the still open end of the tube.

Use the piece of wood that was selected earlier and create whatever shape you choose (make sure to leave enough to create a piece slightly larger than the diameter of the tube). This will be the base of the bass trap. After you have allowed the stain on the base to dry you should find the center of the base and place some wood glue on it and place it on the closed end of the tube. Then, screw in a 1.25" - 1.5" screw for further securing.

Next, place the tube flat on it's new base and fill the tube with sand. 3/4 should be fine but, you can do more if desired. Next, use the extra piece of wood to create a circle that is slightly larger than the tube+the fabric. Find the exact center of the piece and place wood glue on the bottom side. Place the leftover plywood disk in the exact center and then screw in a 1" screw to help hold it in place. You may have to sand the plywood a bit for it to fit in the top but, remember that it should be snug. You should have to beat the thing in so it doesn't rattle around and defeat the purpose of this contraption. You may want to make sure you have a way to get it back out so you can add/remove sand in the future for your own personal preferences.

Create as many as you need/want. Good luck.

By the way, I think this would be a suitable bass trap for mostly corners or at the edges of things (like a desk or on both sides of a bass/guitar amp or wherever it is needed/looks good). If I am horribly mistaken please, someone let me know so I don't go through all of this for nothing and I don't have someone else go through this.

[brandondrury]

I've heard of the tube bass traps, but I've never seen them in my nerdy acoustics books. I'll have to check that out.

Brandon

[valpurgisnite]

Originally Posted by brandondrury

I've heard of the tube bass traps, but I've never seen them in my nerdy acoustics books. I'll have to check that out.

Brandon

Honestly they are more for an upscale home theater system but, form what I understand they are very versatile. I was told that the only reason these are suggested mainly for a home theater system is because it is about combining "pretty" with functionality. Granted the functionality may suffer a bit but, if you have enough of these things (and they are pretty cheap so you can have 10 or 12 of these suckers strategically placed without killing your bank) they can be just as effective as the high end stuff (or so I am told). I have not had the chance to truly test one myself against the higher priced bass traps (because I can't afford them) but, I have seen them in a local studio. There was one in each corner and a few placed in other spots around the rooms.

[brandondrury]

Honestly they are more for an upscale home theater system

That's not a good sign. I've not been overly impressed with my experience with high end home theater people.

Bob Olhson explained to me this concept a couple of years ago. He's in the robo elite of engineer dudes so I'd expect him to be dead on. I'll look into it.

Brandon

[midKnight]

So does anyone have any good sites for inexpensive pre-made bass traps?

a setup from Ethan Winer will set you back about 2-3k, and that's quite a bit more than I want to spend.

I hate to hijack my own thread, but this is pretty cool and basically related, so I thought I would share...

If cash is no object to any of you out there, this company makes pre-built portable vocal booths. I'd love one of these, but as I'm not doing this for a living, seems ridiculous...

Vocal Booths


But please, offer up some links for inexpensive bass traps, as I'd really like to keep the cost down (without building my own).

Also, has anyone used Room EQ wizard? I'm going to start digging into it soon, but looks hard.