sound treating an echoey rec room?

[mitwess]

OVERVIEW:
I have a large rectangular recreation room (for music listening, movie watching, hanging out with friends). The walls are plaster over brick. Dimensions are 40ft x 30ft, 14ft tall ceiling (plaster over drywall). The floor is linoleum over concrete. The room is very echoey. The bass echo in particular is out of control. When a lot of people are in the room, the noise from talking is quite unpleasant.

From researching here and elsewhere. I know that 703 is good for general sound treatment, 705 for bass control/traps. I've read mounting two inches away from the wall helps maximize panel effectiveness.

I'm not looking for studio quality sound. My goal is to make the room quieter (when people are talking) and control the crazy bass echoes.

QUESTIONS:
What ratio of 703 panels to 705 panels would be best? or are there other materials i should consider? How much (percentage?) wall and ceiling coverage do I need to effectively quiet the room?

Is wall or ceiling coverage more important? or are they equally important? i.e. i should have as many ceiling panels as wall panels as a % of their respective square footage?

when hanging panels from ceiling (14ft in my case) what's the ideal distance to mount the panels from?

How much less effective is a mid/hi freq or bass panel mounted 1in from the wall vs. 2inches?

Is it as important to cover the back of the panel (facing the wall) in muslin as it is the front? or can i use poly-sheeting? or do i even need to have a backing?

Any other advice is welcome.

[Glenn Kuras]

What ratio of 703 panels to 705 panels would be best? or are there other materials i should consider? How much (percentage?) wall and ceiling coverage do I need to effectively quiet the room?

Honestly I would just use all 703. It works GREAT for bass trapping and cost about half as much. As far as coverage it really depends on how much you want to tame it down. I would start with around 20% coverage and see how that goes. I would also think about straddling a few 4" panels in the corners to help with bass trapping.

when hanging panels from ceiling (14ft in my case) what's the ideal distance to mount the panels from?

The thickness of the panel. So if they are 2" panels then space it 2" off the ceiling.

Is it as important to cover the back of the panel (facing the wall) in muslin as it is the front? or can i use poly-sheeting? or do i even need to have a backing?

You want to cover the back (if spacing off the wall) with a breathable fabric.

[Weasel9992]

Originally Posted by mitwess

Is wall or ceiling coverage more important? or are they equally important? i.e. i should have as many ceiling panels as wall panels as a % of their respective square footage?

There's no set percentage. I'd cover the ceiling at the reflection points, get the corners, the back wall and the side reflection points...all the usual places for broad band treatment.

Originally Posted by mitwess

Is it as important to cover the back of the panel (facing the wall) in muslin as it is the front? or can i use poly-sheeting? or do i even need to have a backing?

No backing is great.

Frank

[johndykstra]

certainly, this being a rec-room, Glenn I think this is a fantastic opportunity to break out a few examples of your custom art panels...

[mitwess]

so here's a picture/design of what i'm thinking of doing.



6 4in 4ft x 2ft703 base traps on six different corners of the space.

6 2in 4x2ft 703 mid-hi panels on the three walls

4 (possibly 6) 2in 4x8ft 703 ceiling clouds

is this too much / too little? should the placement be different?

notes:
the two black cubes represent two speakers i have mounted that the top of the ceiling on the foreground wall. the right pictured wall has a garage door (which opens and closes). i can add panels to that door (when it's closed with velcro i was thinking, if the room is still too echoey)

the back wall in the picture has two large rectangles recessed in the brick, i was thinking i could put batt insulation in them and cover them with whole rectangle with muslin if the above pictured panels don't suffice.

any thoughts?

[Glenn Kuras]

Originally Posted by dykstraster@gmai

certainly, this being a rec-room, Glenn I think this is a fantastic opportunity to break out a few examples of your custom art panels...

mitwess,
Looks pretty nice to me.

[Weasel9992]

That looks pretty good...it's a good size room, so some diffusion might be in order as well. Depending on what sort of character you're looking for in the room you could either thin out the absorption some and add diffusion or simply insert diffusion between or on top of the panels you have on the walls.

Frank

[mitwess]

thanks everyone. what's the easiest / most inexpensive / useful diffuser to make? any info/tutorial links would also be appreciated.

[johndykstra]

diffusion is totally unnecessary if you are just looking to deaden the echo in your rec room.

I think three walls may even be overkill.

Hit some corners, line two conjoined walls about as heavily as you have rendered in your sketch file, and throw some rugs down before you do clouds. After that, if you still aren't satisfied with the sound, then start hitting the third wall, and more corners. Still not good? cloud time, and more corners.

Regarding the wall traps, try to vary the height a bit, so as to not have a bare strip running the perimeter of the wall above and below the traps.

[avare]

Originally Posted by dykstraster@gmai

Regarding the wall traps, try to vary the height a bit, so as to not have a bare strip running the perimeter of the wall above and below the traps.

+1

Repeatedly,
Andre

[johndykstra]

Andre, nice to see you still around! We will have to chat again sometime

[Glenn Kuras]

Regarding the wall traps, try to vary the height a bit, so as to not have a bare strip running the perimeter of the wall above and below the traps.

+2!thumbsup

[xaMdaM]

Originally Posted by dykstraster@gmai

Regarding the wall traps, try to vary the height a bit, so as to not have a bare strip running the perimeter of the wall above and below the traps.

+3

Vary their sizes too...

It's a rec room... it doesn't have to be scientifically correct.

There is such a thing as chaotic structure... Your room would certainly qualify.

There's speaker's ceiling mounted, right? I'd stick some 703 on the ceiling:wall corner, extending behind the speakers in a mini super-chunk... wrap it in fabric.

Make some of the panels 12" wide, some 24", some 36", some 18"... make em' look nice and have fun with the patterns.

Set them in a pseudo random order.... say, all the 12" wide panels at 12" below ceiling height and all the 36" panels 24" from the floor, maybe the 18" panels 18" from the ceiling and the 24" panels centered in the wall... any kind of pattern really.

If you have hard ceilings, you can certainly do soft goods on the floors (like rugs) and it'll help, but then you gotta clean carpets/rugs. If that's a no-go, then I'd extend your random chaos model to the ceiling with various sizes of clouds.

I would put larger clouds over areas where you would call primary quite areas, listening areas or conversation areas.

A slick way to suspend them is to put a 2" washer on the bottom side, then tie 20lb test line to a nail and push that through the washer and let it lock in place... wrap the 703 in fabric and either stitch the corners or safety pin the corners. Suspend where ever you like... including at random heights from the ceiling... with 2" being as close as you want to be, and probably no more than 10" away from the ceiling.

[johndykstra]

I like the "sound" of all of that