Some help needed...

[MetalGod]

Hi all,

Now that I've finally got some proper monitors I have begun to realize how bad my room is (no surprise really ), especially in the bass region.
I've been reading up on how to make your own bass traps, and it seems straight-forward enough, but my problem is I have a very odd shaped room. It's right under the roof, so is in the shape of an extruded triangle (see attached diagram) measuring 6.55 meter (21.5') x 3.75 meter (12.3') x 3.35 meter (11').

The main problems are in the range 30 Hz - 100 Hz. I've got a big dip at 60 Hz, a big peak at 73 Hz and a HUGE peak at 90 Hz. After that it's fairly good all the way, except for some fairly deep and narrow dips at 198, 222 and 530 Hz. I also have modal ringing at several frequencies between 33 Hz and 90 Hz.

All the forums and tips I've read says bass traps are best positioned straddling the corners (thinking membrane type traps here) but that wouldn't work in this room (or it would at least be tricky to mount them). What's the best option? Place them elsewhere? Try other types of traps? Anyone got any experience taming oddly shaped rooms?

Anyway, any help/pointers/information would be highly appreciated.

Cheers,
MetalGod

[brandondrury]

What's the best option? Place them elsewhere?

Everywhere!

Corners are certainly areas where low end builts up, but they certainly aren't the only place. The ultimate goal is for low end to shoot out of your studio monitors, hit you ears, and not come back. The omnidirectional tendencies of low frequencies means that you can you treat essentially anywhere.

Depending on you budget and goals, I'd say the more bass trapping, the better. It's my understanding that you can not over-bass trap.

With that said, before you go crazy with bass traps, I'd find the most accurate position in the room.

Brandon

[String7th]

I think a better position would be in the middle, rather than against a wall, and about 3-4 feet away from the longer wall, which it looks like it is close enough. I suggest rigid fiberglass boards or mineral wool depending on your budget, to fill in that corner on the celing. 2 inch thick board, 2 feet wide, and long enough to fill the whole corner on the celing. The if you have the budget, do the same thing on the 2 floor corners.

This is called broadband absorbtion and reduces a lot of the low end coming back to you from the walls and corners. When you get more money to invest in acoustics, read Ethan Winer's FAQ about the first reflections and where to put your expensive bass traps.

[MetalGod]

Thanks for tips guys, really appreciate it. I will try out different positions and see how they compare. By the looks of it I can build bass traps and absorbers relatively cheaply, so it will be fun to experiment, especially since my goal is not only to improve my room but also to understand the basic principles of acoustics. I have an inkling this room will be tricky to tame, so plenty of opportunity to learn stuff

Another question: I've already gone through Everest's Master Handbook of Acoustics and it was really good (though I have a feeling I need to go through it again to figure out the parts I didn't get ), but are there any other books that may be worth getting? I'm really keen on understanding acoustics but I'm not sure what other books would be useful/helpful. Any tips?

Cheers,
MetalGod

[String7th]

Acoustic design for the home studio.
They actually go through the design of a room similar to yours. This guy simplifies sound waves and how they travel, once you got the basics, then read Ethan Winer's stuff about building better bass traps.

[brandondrury]

my goal is not only to improve my room but also to understand the basic principles of acoustics

Check out The Master Handbook Of Acoustics. I highly recommend it.

[adorian]

MetalGod if you have so DYI info on bass traps I'd appreciate you sharing.

I've personally started to rely on my headphones at home more than I should have but straight 8 years of bedroom recording on the same pair and I know what to expect. My mix test is my VW Monsoon system - that usually translates best anywhere I've tried it. I think it is also something I can rely on more on the fact that I've used it forever and I leave the studio with a takeout CD every night.

[MetalGod]

Sure, no problem. I've found a few links:

DIY BASS TRAPS - Index

Acoustic Treatment and Design for Recording Studios and Listening Rooms

YouTube - How to make a Bass Trap Acoustic Panel (Tutorial)

Bubba's bass traps - Audiominds

YouTube especially seems to have a lot of instructional videos for how to build bass traps and other acoustic treatments, I'm going through all I can find now.

Hope this helps.
MetalGod

[adorian]

THanks, I'll check them out.