bass trap placement and hanging

[dean]

ok, so i am having some higher bass/low mid issues in a smallish tracking room. i am not positive but i believe the frequency around 104hz and its multiples. its singable but at the lower end of my range, although i don't have a very deep voice.
i built 4 frames with 2 - 2in 703 batts in each for bass trapping. i was wondering if it really matters what corners the traps are in. unfortunately i can't really place them in the tri-corners where the two walls meet the ceiling or floor due to the odd shape of the room and the placement of doors, window, etc. i wanted to place the traps where the walls meet the ceiling. is it any different vs the floor? also, do they need to be placed evenly around the room or is more towards one end ok? let me see if i can describe the room to the best of my ability. here is an approximation that should be pretty close. the top of the picture is where the issue is most obvious. the room is 9'2'' tall. there is a door to the left of the '14ft' mark and a window to the left of the '8ft' mark to the control room.

____14ft_____
|..................\
|....................\
|15................/
| ft.............../
|................./
|.............../
|............../
|__8ft___/
for some reason when i post this, the diagonal lines were being moved to the left so i put all the dots in to keep the right, angled wall in place.

the '8ft' wall has just been covered with mass load vinyl to help stop some sound into the control room and will be mostly covered with a DYI diffusor i made as well as a little bit of 2in eggcrate foam mixed in with the wood. the diffusor is basically made of different depths of wood furring strips running the width of the wall in a somewhat random pattern of 1in, 2in and 3in depths with the occasional strip of a 3" to 5" piece of foam to even out some gaps and make fitting everything easier. i know its not perfect and scientific, but i hope it helps a little (at least it looks pretty cool!)

any other suggestions are welcome as to how to treat the room to improve the sound. i am looking to make it on the 'dead' side but not totally dead. really just nice and balanced. i also have 4-2in pieces of 703 i am wrapping to hang on the wall or make some clouds. i would prefer to not do clouds if i can. i would like to keep the ceiling feeling as high as possible. with the bass traps already made, is it worth spacing the extra 703 away from the wall for more trapping?
you can go to this link to see a bit of the room. its the one with the blue wall and does not have the diffusor in the pick as it is not totally current.http://www.facebook.com/home.php?#!/...2873236?ref=ts

i know this is a lot, but any help is appreciated.

cheers,
dean
euphonicmusicschool.com

[Rod Gervais]

A corner is a corner, they are all the same when it comes to getting the job done.

Wall to wall - wall to ceiling - wall to floor - no difference........

If you can't get to the tri-corners - then work with what's left.

You have your work cut out for you with that room,,,,,,,,, small odd shaped rooms are always a challenge........ the foam isn't helping you a whole lot with your problems either........

[dean]

thanks for the reply!
ya, i realize the foam does nothing for the low end. its taming the hi's but now its unbalanced in the room. do you think the 4 extra 703 panels will help in addition to the bass traps? should i try and space the extra 703 panels an inch or so off the wall? will that make a difference?
also, in your opinion, is my DYI diffusor actually diffusing or did i just make a very time consuming wall decoration?

cheers,
dean

[Space]

I wonder what the effect of the low nap carpet is that seems to be in all of the rooms.

[Rod Gervais]

thanks for the reply!
ya, i realize the foam does nothing for the low end. its taming the hi's but now its unbalanced in the room. do you think the 4 extra 703 panels will help in addition to the bass traps? should i try and space the extra 703 panels an inch or so off the wall? will that make a difference?
also, in your opinion, is my DYI diffusor actually diffusing or did i just make a very time consuming wall decoration?

If you could increase the 703 to 6" total it would be much better - and I would fill the corner behind them will fluffy insulation (which will give you a heck of a lot of additional bang for the buck).

I doubt if your diffusor is going to do much at all............

Rod

[Rod Gervais]

I wonder what the effect of the low nap carpet is that seems to be in all of the rooms.

Sucking the highs and high mids out of the room - BUT - I can't see the ceiling to see if it is hard or absorbent - if it's hard then the end result (room wise) is about the same - although early reflections off the ceiling will still plague you a bit.. much easier to put down a throw rug to handle a reflection off the floor than it is to do something ad-hoc with the ceiling...........

[kmetal]

don't know exactly what your tracking in there. a vocalist standing up around 5'-6' high is closer to the ceiling than the floor. depending on the angles you could have some upleasent reflections into the mic from the ceiling. i know how annoying it is, but treating the ceiling w/ some flush mounted absorbent can help. granted it may barely help your bass issues. corners are your best bet w/ that, visually, and acoustically.

[soapfloats]

This is a side note, but I believe it pertains to the OP's concerns about low frequencies and appropriate bass-trapping...

Rod - In your opinion, is it better to have:
A) 703 or equivalent facing the corners w/ pink fluffy behind
B) Superchunk method
C) Either/or, depending

I typically work in smaller control rooms (and lately smaller tracking rooms), and this is clearly a concern for the beginner/intermediate engineer.
Obviously every room is different, but low-end control seems to be a common issue.

[Rod Gervais]

This is a side note, but I believe it pertains to the OP's concerns about low frequencies and appropriate bass-trapping...

Rod - In your opinion, is it better to have:
A) 703 or equivalent facing the corners w/ pink fluffy behind
B) Superchunk method
C) Either/or, depending

I typically work in smaller control rooms (and lately smaller tracking rooms), and this is clearly a concern for the beginner/intermediate engineer.
Obviously every room is different, but low-end control seems to be a common issue.

Well the real answer is C.

A lot depends on the actual needs in the room.

Although the Superchunks will deliver much more room treatment in the same area, if you can get the job done with the fluffy insulation then you are getting a lot more bang for the buck.

The Superchunks are quite expensive due to the sheer amount of materials required.

[kmetal]

what kind of room mode analysis do you have, dean? it helped me alot, to test my room after i placed absorbent panels in the mirror points, and treat the room modes (bass holes/buildups) specifically. Since your room is asymetrical, as is mine, i think testing is the efficient way to satisfying result. there are plenty of published frequency responses of building materials, which you can plug into the spreadsheet that comes w/ rod's book, that'll give ya a good idea of what can be done. my room mode tested .2 hz away from the math, in a rectangular room, which is what most general room calculations are based on.
i suggest that you test your room modes from all the corners you can, they will be clear as day on a "fancy lookin" waterfall plot, then decide where you want to put your money. i leave you w/ get a radio shack digital SPL meter ($40) and hometheatershack's analyisis program (free). i'm sure there are other reputable free testing programs out there, that's just the one i use.