rear wall symmetry

  • Thread starter Thread starter CIRO
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CIRO

CIRO

Eu mesmo
My mixing room is 11 X 9,3 X 8,8(h), and has some treatment:

*Bass traps (4" rockwool) floor to ceiling in the left/right front wall
*4" rockwool in all rear wall/ceiling corner.
*2" 2'X2' rockwool in the "RFZ"
*One 2' X 8 ' panel trap (1/4 plywwod, 4" depth, sealed)

The rear wall is my problem: I have a door in the left corner and would like to put some treatment in the other corner (same 4" traps, or even a superchunk). Well, I have the panel (tuned ~100hz), which I can put beside/near the door to "some symmetry" , but is not broadband...

Question:
Is a good idea have some treatment in the right rear corner and another treatment in the left? Or no treatment is better, in this case?

Tks

Ciro
my songs
www.soundclick.com/openstation
 
I'd suggest keeping it symmetrical, but with treatment. You can simply put broadband absorption on the back wall/door, and have the bass traps on the wall-ceiling corners.

Also, I've listened to a couple of tracks. Very nice work there. Sounds professional.

You've double posted...
 
I'd suggest keeping it symmetrical, but with treatment. You can simply put broadband absorption on the back wall/door, and have the bass traps on the wall-ceiling corners.

Also, I've listened to a couple of tracks. Very nice work there. Sounds professional.

You've double posted...


Hey CIRO,

I have a door in my rear wall corner so I have done what pandamonk has suggested to you. I have a bass trap (4" OC703) in my rear wall/ceiling corner and I have 2" OC703 with 2" Auralex over the top on a panel in the middle of the rear wall. I would like to have some bass trapping in the rear wall corners but I can't do it and retain symmetry so I did the rear wall/ceiling corner and it is working fine!

Gorty!

Here's my rear wall!

CopyofStudio-Guitars014.jpg


Another shot!

CopyofBassTrap012.jpg
 
Thanks,Gorty!

("you must spread some reputation...")

Well, the the truth is: dimensions don´t helps, modes are spaced too far in my small room, and bass response ...:(
Then, each improvement is welcoming.

Nice job you did.I have 4" in my rear wall/ceiling (entire) too...a trap in the middle of the wall seems to be the next step,a "must have" (maybe I´ll try a 4").

And man, do you use these two 4X12 cabinets at same time? (I saw an entire pic in another thread too...)

The ears still working?:eek::D

Tks again

Ciro
www.soundclick.com/openstation
 
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What Gorty was showing (same rep problem...) is exactly what I'd recommend. Instead of going in one corner and not the other, I'd go all the way across the room side to side up at the wall/ceiling corner.

Bryan
 
Thanks for helps again, Bryan!

Definitelly, I´ll go for the bradband in the rear wall, and maitaining the symmetry...

I´m thinking in a 4" rockwool w/ 4" gap.
In this case, what´s better? A "closed" air gap (with wood in the sides) or an "open" air gap performs well too?

Ciro
www.soundclick.com/openstation

And "you must spread before....Bpape again"
 
I'd do the frame and rout/drill some holes in the framing. Mount it straddling the corner at 45 degrees to catch direct from length and height dimensions and have a nice variable airgap behind it.

Bryan
 
Bryan:

I dont know If I understood , but you´re talking about 45º angle ... I already have the entire rear wall/ceiling with 2 2' X 4' 4" rockwool, I was talking about the advantage (or not) by an air space with a (for example, a 4" bass trap + air gap) directly behind my mix position (considering I give up the
idea of an rear floor/ceiling trap only in the right side, due to the symmetry issues...)



Ciro
www.soundclick.com/openstation
 
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Bryan:

I dont know If I understood , but you´re talking about 45º angle ... I already have the entire rear wall/ceiling with 2 2' X 4' 4" rockwool, I was talking about the advantage (or not) by an air space with a (for example, a 4" bass trap + air gap) directly behind my mix position (considering I give up the
idea of an rear floor/ceiling trap only in the right side, due to the symmetry issues...)



Ciro
www.soundclick.com/openstation


CIRO,

From what I have learnt, 4" trapping + 2" air gap is equivalent of
6" trapping. For your back wall I would suggest 4" Rockwool with no air gap or 2" Rockwool with a 2" air gap. Broadband absorption is the aim for the rear back wall for reflections.
 
Thanks,Gorty!

And man, do you use these two 4X12 cabinets at same time? (I saw an entire pic in another thread too...)

The ears still working?:eek::D

You're welkom CIRO,

And yes...I do use both quad boxes together, I seperate them by about 6 feet and they sound awesome. On stage I mic each cab seperately and have the Marshall left and the Laney right. Two completely different tones from the two boxes being driven by the same 100Watt Valve Head! :)

My ears.........PARDON!!!!! :D
 
I like it, I used to use a Fender "The Twin" (mine) plus "any other good amp" in this stereo configuration, with a Boss stereo chorus, was a great set up, makes all the difference on stage.

Ciro

www.soundclick.com/openstation

I love using the two boxes. The Laney is very mid-range/cuts through the mix effortlessly while the Marshall has a nice rounded warmness.
 
I know that´s not your case, but ...:D

Vinnie Vincent and Paul Stanley used (brazilian tour 1983) "walls" of Marshall cabinets (turned off) and little boogies behind the curtains :eek: Well, that´s what people say.

Ciro
www.soundclick.com/opensation
 
Whether or not you need the gap depends on how low the nulls you're getting off the back wall are.

General rule of thumb is no more gap than thickness of absorbtion. 4" with a 2" gap will, as Gorty said, be pretty close to the same as 6".

Bryan
 
Thanks again Bryan!

The nulls are "ok" at (center of) back wall , as well the peaks, altough they still "strong" (but only the 125/280 hz peaks, not the nulls, which are "ok" too) at mix position (38%). That´s why I was thinking about the "air gap" and even put more 4" traps...but , is funny : shouldn´t be the "38% mix position" the "flattest" place?:confused:

Ciro
www.soundclick.com/openstation
 
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In theory, 38% puts you in the best place to avoid the huge AXIAL modal issues which are the strongest one. That said, there are still tangential and oblique modes to deal with that can sometimes interact with the axials, the speaker position, the actual distance to the rear wall, etc. and cause some issues.

My advice would be to try checking things say 6" farther forward than you are now. Usually staying in that area from 33-38% is the best range. Moving the other way toward 40% puts you in some nasty axial issues.

The 38% is not a hard and fast rule but more of a 'lesser of all evils' always decent starting point. Moving a couple inches here and there is not verboten...

Bryan
 
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