CLX & Wall prep

[SSingh]

Hi, I'll be installing a pair of CLX & Descent in a largish room soon (33' by 25'). The CLX will be 4' from the wall. I've been working with an acoustic design company who have recommend the following:
- 2 absorption panels behind each clx (auralex absorbers covered with acoustically transparent fabric)
- a custom made diffusion panel of random wood blocks in the middle (from edge to edge of the 2 clx).

my question really relates to the diffusion panel. should it be that large, ie it almost overlaps the clx. I'm planning to place the CLX 8' apart to create an equilateral triangle to the main seating position so the acoustic specialist has recommended that the diffusion panel be the same width.

I'd appreciate any experiences, comments, thoughts etc...

 

[Jimna]

are you putting the diffuser behind the CLX also? i would guess it would serve you better to use all absorption on the front wall behind them and put the diffuser on the back wall on the other end of the room. jonfo will have a definitive answer here, and may prove me wrong also.

 

[David Matz]

Not sure if you are committed to purchasing from your acoustic expert, but contact Ethan Winer at realtraps.com. The site has videos that may answer some of your questions. He offers great products and free advice.

 

[JMAUSGP]

Another thought, is that your journey with your CLXs will be one of discovery.

I started with 2 CLXs with sound absorbtion panels behind and to the side. I also put bass traps floor to ceiling in each corner.

Then as I went along I added more and more panels, listening along the way to see if I liked or disliked the effect.

I eventually added a second pair of CLXs and subsequently doubled the number of sound absorbtion panels to the room, including adding some to the ceiling. And I don' know that I am done yet.

The point being, start out with what you have and from time to time add panels and diffusers and listen to the effects. There are some great threads on here that will help you in the placement of your sound panels.

But most importantly, listen and enjoy your CLXs, they are one of the great speakers of all time and should be enjoyed no matter what the configuration.

 

[Gordon]

I look forward to your thoughts on the diffusion in the center. I've a bunch of junk between my speakers and don't care for it but the room demands it.

I'm certain Jonathan will chime in here shortly

Gordon

 

[Bernard]

I suggest that you buy Jim Smith's book, "Get Better Sound".

 

[JonFo]

...

my question really relates to the diffusion panel. should it be that large, ie it almost overlaps the clx. I'm planning to place the CLX 8' apart to create an equilateral triangle to the main seating position so the acoustic specialist has recommended that the diffusion panel be the same width.

I'd appreciate any experiences, comments, thoughts etc...

Hi, my recommendation would be to have additional absorption between the speakers instead of diffusion.

First, because the diffusion placed *between* dipoles like that is not really managing any rear-wave energy, it would 'see' mostly room reflected sound.

Using absorption across the front wall helps manage the rear-wave energy directly behind the speakers (to minimize comb-filtering) and by covering the space between, it minimizes out-of phase mid-bass energy (increasing the 'punch' of the speakers in that critical range).
It also minimizes front wall reflections of room energy.

So the front wall should always either have absorption (preferred for dipoles) or diffusion, but never a 'flat' wall.

I'd recommend the 3D diffusers be placed on the opposite wall (behind the listener), assuming the listeners are at least >5' away from that surface.
Given the size of the room, that should not be a problem.

 

[Beakman]

If my CLS setup is any indication of what you may expect from your CLX, here's what I'm experiencing: My speakers sound better with no absorption on the front wall nor heavy diffusion. What I do have is absorption on the side wall side of the side/front corner junction. the front wall has medium weight drapes and irregular surfaces (small shelves).
With the plethora of differing opinions, both by published experts and anecdotal experiences related as present, I found one thing that has helped with my setup more than I expected - a book on studio recording.
I forget the title (I'm on the road working) but one or more chapters deal with soundstage, depth, different speakers as monitors, mix consistency, phase, etc. as laid down on tracks as well as the end listening. It's an education that will lay to rest some mumbo-jumbo in the High End stereo world.
Research mix and placement patterns such as the "I", "V", "W", for a more accurate speaker placement. Research monitor soundfields in regard to type and placement and to what you can expect a speaker can and can't do.
I'm not saying that all the tips and advice I've gotten from here and listener specific literature are bunkum, mostly not, but the first thing that becomes evident when researching the recording end of things is that the hard rules purported by the listening cognoscenti are really only suggestions and starting points.

 

[SSingh]

thanks....

thanks for all the opinions given. i've decided i'll start with a bare wall and then try out the options of all absorption or a combo of absorption/diffusion. i'm doing a dedicated HT room at the same time so there will be both kinds of panels handy to test out which works. i hope to report back in a couple of weeks.

the HT room should be interesting, its fairly small so i will be using 5 vantages (front 3 in a row, middle one behind an acoustically transparent screen)..meanwhile everything is on hold till the renovation of the rest of the home is complete.

 

[Len44]

thanks for all the opinions given. i've decided i'll start with a bare wall and then try out the options of all absorption or a combo of absorption/diffusion. i'm doing a dedicated HT room at the same time so there will be both kinds of panels handy to test out which works. i hope to report back in a couple of weeks.

You're [way] overdue. And we are interested. How is all this coming along? What have you discovered along the way?

 

[Len44]

If my CLS setup is any indication of what you may expect from your CLX, here's what I'm experiencing: My speakers sound better with no absorption on the front wall nor heavy diffusion. What I do have is absorption on the side wall side of the side/front corner junction. the front wall has medium weight drapes and irregular surfaces (small shelves).
With the plethora of differing opinions, both by published experts and anecdotal experiences related as present, I found one thing that has helped with my setup more than I expected - a book on studio recording.
I forget the title (I'm on the road working) but one or more chapters deal with soundstage, depth, different speakers as monitors, mix consistency, phase, etc. as laid down on tracks as well as the end listening. It's an education that will lay to rest some mumbo-jumbo in the High End stereo world.

Interested in name of the book you mention. Also, with Aeons, Ascents, and Summits (yes, I fear where this is going), I, experienced better sound with
just a bare front wall (behind the speakers). When I reversed the room, which put the speakers in front of heavy drapes, it really seemed to take the life out of the music. Yet, there are those who apparently experience good results by applying absorption behind their speakers.

Adding to my puzzlement is that Martin-Logan suggests that a bare wall behind the speakers should work just fine, and that the wall behind the listener should use absorption (like my initial set-up). They seem to know what they are talking about, at least in my experience.

So, all this leaves me a bit

 

[SSingh]

final result

ok here's the final result. after some experimentation with stuff on the wall, i decided to panel out the entire wall. the wall was divided into 3 sections and a custom panel made top to bottom and fully across. the middle section is meant to be a diffusor and has timber slats (2.5" deep by 1.25" across) from ceiling to floor. the entire structure has a rockwool backing. the 2 side panels are felt over perforated board over the rockwool (1" felt) and the felt is covered in a acoustically transparent fabric. i hope the attached photo helps make sense of this.

the main benefit i have seen over a bare wall is loud complex pieces (orchestral, heavy rock or the punjabi bhangra music from my roots) has much less of a jarring edge to it. Overall it seems to help resolve detail better. the structure did cost quite a bit to put up, with lots of pain to my acoustic contractor but imho it was worth it. thanks for all the input you guys gave on this thread.

 

[sleepysurf]

Gorgeous setup! Well done!

-- Sent from my Palm Pre using Forums

 

[Hocky]

Agreed, looks awesome.

 

[Lagonda]

Nice clean look, it's so hard to get good sound in modern home. Well done!!

 

[Ron]

I like your taste. I like the CLX's also. Great room and speakers.

 

[repman]

The room looks fantastic !! I bet it sounds as good as it looks

 

[Gordon Gray]

FWIW, MBL recommends no treatment on the wall behind the speakers.

GG

 

[FoxMulder]

Hey Gordon, how about pics of your new MBL's in your room? I see you still have the Summits pictured on your system page.

 

[SSingh]

FWIW, MBL recommends no treatment on the wall behind the speakers.

GG

be that as it may but frankly the clx sounded like crap on loud noisy pieces with that solid concrete wall behind them. the theory of a recommendation and the reality of a particular setup may differ somewhat