Diffuser panel design - overrated?

Are these backfiring speakers? The speakers I use our front facing with no ports in the back, so with these be a good thing for diffusers in the back of the speaker?

So my encyclopedia Britannica Collection has got to go?

I recently purchased a pair of diffuser panels, quite cheap (they are made out of hardened polystyrene foam) to serve as OPTICAL background behind my midrange and high frequency horns (I think diffusers look cool). The way they are positioned I was really not expecting ANY effect, but it turns out those two weirdly placed diffusers improved the sound of the room A LOT. So yeah, I would say professional diffuser panels are well worth trying and most likely way more efficient than a bookshelf with random book depths ;-)

Kota1

Thank you for the video link. Immediately note that this is a one plus hour video. No doubt lots of valuable info here in.

If these audio guys want to improve their flow rate of product they need to become more concise. My gosh spending an hour listening to a meandering Journey through the world of diffusion add absorption looks very exciting.

I’ll give it some time

Anthony Grimani states you have two types of diffusors, 2D and 3D. He stated to use the 2D diffusors in the front half of the room and 3D diffusors in the back half. The 2D diffusors have to be deep enough to impact certain frequencies so a book case wouldn’t cut it. You can check out Auralex Metrofusors for 2D. 3D diffusors by Auralex include the Geofusor, the the Tfusor and the Hemisphere. The Tfusor and Geofusor can also be filled with polyfil or rockwool if you also want to give them some absorption capability. I used Auralex Sustain series diffusors in my setup that are made from bamboo but were discontinued. You can check Anthony’s brand, Sonitus: I really like this video:

I’m in agreement with @emergingsoul up to a point. While it may not be rocket science there are methods of approach that can save you a lot of time and money. When changing to the space I use now I brought in an acoustic engineer to measure and advise on the best placement solutions. At the end of the day everything was placed and sizing/layout for panels was complete (I use absorption as opposed to diffusion). It took a couple of weeks to have the panels fabricated but once installed everything came together.

I’m definitely a believer in the importance of their use but it seems there are a lot of instances where the balance between a live space and dead space swing too far from what is necessary.

@emergingsoul  , for someone starting out in the diffuser panel game, do you have a cost effective recommendation for behind the speakers?

@emergingsoul Thank you for the all too rare (on this site) common sense.

I have seen the Gik acoustic stuff and it's not very nice to look at.  Whenever I walk into a room I see similar things from GIK.  free consultations I have done and they just wanna load you up with panels. Hardly independent. 
 

Acoustical treatment is a nightmare to deal with.  Just buy sub traps for the corners, add some absorption panels to the first reflection and a diffuser panel or two behind the speakers and you're done. It's not rocket science. And if you really wanna have some fun put the panels on your damn ceiling.  And get shades if you have windows.  It's not rocket science.

@jumia 

If you’re serious about getting the best possible sound in your room, why not reach out to GIK Acoustics for a free consultation? Every room is unique and should be treated as such. 

People have diffuser panels on their wall, they're not very big sometimes.

How much surface area do you need in a 14 x 16 room for it to make a difference?

Isn't the diffuser panel competing with all the other irregular things scattered about?

More on the subject:  

Just a few db differences can allow for separation in timing and level for the given individual ear. Each ear being different.

So diffusors can work for one speaker, and room, and not the next. then we introduce different ears and we've got 3 variables that dictate the seeming quality of a diffusor. As all three have to be aligned for it to all calculate out, but none of the three variables can be accounted for.

Then the electronics, wiring ac quality, and so on. Actually, 4 uncontrollable permanently variable, er, variables.

My predictions, if I have any... on the efficacy of diffusors... is in no way a slam dunk for the next person.

A general pattern emerges, yes, under the umbrella of the four variables. But no hard number will ever emerge.

To argue this, well one better come armed. :P

@jumia Wrote:

So just by rearranging your bookshelf to create an uneven surface area, isn’t this achieving the same thing.  It's not rocket science.

See below:

Mike

@erik_squires Wrote:

I stand by my answer based on years of reading and experience. I suggest before you knock what you don’t understand that you do some reading and listening. 

I agree!

Mike

Conceptually what you say is true, but it's the details that matter.  Haphazard vs. controlled.  Random vs. broadband.  Either path can end up with good results, but one is far more efficient.

This is a cool answer, but if the diffuser is behind the speakers most of the sound is already going to the listener without going to the diffuser first.

The rocket science is in controlling the direction, and frequency spread of the diffusion. The width of the recesses and their frequency affect this. Also some diffusors have multiple different scatter patters going on at the same time to change the range at which they are effective.

No, they are not overrated, but may be too expensive, IMHO. ;) 

What they do is give you a high density solution, which allows you to precisely tailor a solution.  Meaning, for each square foot of wall or ceiling space you get a lot of effect.  Also, diffusion, especially between the speakers, really improves imaging and clarity, not by deleting sounds but by increasing the volume you get at your ears in the right, diffuse manor that actually helps you hear more.