diffusor

woodsyi · « **on:** 2 Sep 2006, 02:34 am »

After corresponding with Alan from SRL Audio, I ordered a 4'x6' Max Diffusor panel. http://www.srlaudio.com/diffusion_panel_gallery.htm
I received it last week but I only just was able to install it on my back wall in my room. This augments 10 real traps, 4 gik panels and 4 8th nerve corners. I will be doing a lot of listening this weekend but I will just post the initial impression. I am hearing more on my midhighs and highs. I am hearing clearer guitar riffs and piano notes. I will post pictures and further impressions later.

woodsyi · « **Reply #1 on:** 2 Sep 2006, 04:41 pm »

Hot damn, this diffusor works. In my research more have said that diffusors only work in large rooms than not, but some more recent articles have suggested that it could be good even in small rooms when used properly with absorbers. The gist of it was that for diffusors to work properly they need to be of large size and until now they were priced too high for most home use. Guess what? It works in a smallish room too. With this panel on my back wall 22ft from the front wall, I hear amazing things from my listening position 8ft off the back and 14ft (speakers are 5ft off the wall) from the front. With a bunch of absorbers I had already tamed the bass issue for the most part. 3 micros on early reflection points (top and sides) and 2 micros on the front wall behind the speakers were placed to control mid to high frequency to some extent. The addition of this diffusor just kicked my room up a huge notch. It has added air and space around the voices and instruments in the most welcoming way. I am hearing tonal and spacial separation of voices and instruments I did not discern before. I can almost hear each bristle of a brush that just sounded like one noise before . There is just the right amount (for me) of reverb to make high notes linger that is so nice. This things is a keeper.

I will get a picture or two soon but, man, I just want to listen to my divas more. BTW, the vinyl sounds so good with this extra resolution in the upper register.

I

bpape · « **Reply #2 on:** 2 Sep 2006, 06:33 pm »

Congrats.

You're actually right on the edge of being far enough away from them for them to work. The size thing with diffusors has more to do with how low in the spectrum they'll be effective. Some relatively small diffusors will work well in the upper mids and highs.

BTW, I took a look at those diffusors - very interesting design - especially the pseudo-poly type layout in the center and at the edges.

Bryan

Rob Babcock · « **Reply #3 on:** 5 Sep 2006, 04:40 am »

What do they cost? I didn't notice any ordering info in your link. Do you have any pictures of your install?

woodsyi · « **Reply #4 on:** 5 Sep 2006, 12:16 pm »

Rob,
They are still not dirt cheap and shipping cost can be expensive as my 4'x6' panel had to be freighted. I suggested to Allen that he should look into shipping to nearby pickup points as those services are much cheaper than door to door service. I will let Allen chime in with the prices as I don't know what the list prices are. The Panel is soundly built and is sturdy. I banged it around a little bit as I had my wife "help" me take it down stairs to the basement. Hakuna Matata! I will post pictures soon.

gjuodenas · « **Reply #5 on:** 5 Sep 2006, 03:33 pm »

I have been following this thread re: the SRL diffusors I have designed and I would like to correct one comment. What influences the low end response of the diffusor is the thickness not the vertical and horizontal size. The vertical size determines the vertical area on the wall that is diffused. The horizontal dimension determines the type of diffusion. If smaller diffusors are mounted in multiples there is a negative effect that happens. there is a lobing effect which is counter to the dispersion effect. When using smaller diffusors in multiples you have to mount one that is a negative (inverse of the pattern) every so often using a complex formula. The larger the prime number that you can use in computing the pattern the better, this determines the horizontal width. I target the low to high mid range which in our tests has shown to be the most effective area for dispersion.

George Juodenas

bpape · « **Reply #6 on:** 5 Sep 2006, 04:15 pm »

Hi George.

Guess I wasn't very clear. The dimensions I referred to was more the depth of the wells (what you refer to as thickness) and also the width and depth of each of the wells in relation to the wavelengths to be diffused.

Sorry for any confusion.

Bryan

woodsyi · « **Reply #7 on:** 5 Sep 2006, 04:28 pm »

Hello George,

Welcome to AC. I initially thought of doing DIY project where I would buy a bunch of thermoplastic skyline tiles and gluing them on a board. Then I read something about a prime series needing to run a full period to be effective. That's when I decided to go with your design rather than work out my own formular to try to make a diffusor. I do have a question on the depth of your design. Most models that I have seen featured 8" to 10" maximum depth to be tuned around 1k hz. Yours is less than that. (I am not complaining

) I know it works but how does it work?

gjuodenas · « **Reply #8 on:** 6 Sep 2006, 02:43 pm »

I am glad to be posting and will do more so,

Schroeder formulas allow for a range of values but he did suggest what he considered to be optimum. I have used his optimum values with a very slight modification (that is why I call it a modified Schroeder design). Each chosen Prime Seed (Prime Number) sequence results in a different maximum well depth for the same 1Khz design frequency.

George Juodenas

woodsyi · « **Reply #9 on:** 7 Sep 2006, 02:03 pm »

Okay, uploading pictures is like pulling tooth here. I hope this thing works.

For a pespective, this is how it is installed.

To get a sense of the room, this is the front where you can see the same sofa.

bgewaudio · « **Reply #10 on:** 7 Sep 2006, 04:27 pm »

Nice 2 ch woodsyi

Looks like you've got alot of first orders and trapping taken care of.

How does this room perform sonically?

woodsyi · « **Reply #11 on:** 7 Sep 2006, 05:22 pm »

Quote from: bgewaudio on 7 Sep 2006, 04:27 pm

Nice 2 ch woodsyi

Looks like you've got alot of first orders and trapping taken care of.

How does this room perform sonically?

Thank you. I also stuffed the corners and edges above the ceiling tiles with RU30 insulation (as compressed as I could) and the tiles are rated at .5 NRC (don't know at what frequency but assumed high). With the addition of the diffusor, I really like the acoustics of my room. I mean I can crank out some serious bass with my woofers but they behave. Human vocals (the most important factor in music for me) are really good now. I would recommend diffusors to go with absorbers. You get clarity without diminishing the output.

DTB300 · « **Reply #12 on:** 7 Sep 2006, 05:55 pm »

Quote from: woodsyi on 7 Sep 2006, 02:03 pm

Okay, uploading pictures is like pulling tooth here.

Woodsyi...You have added a lot more traps and acoustic treatments since I have been there.

Dan

woodsyi · « **Reply #13 on:** 7 Sep 2006, 06:06 pm »

Quote from: DTB300 on 7 Sep 2006, 05:55 pm

Quote from: woodsyi on 7 Sep 2006, 02:03 pm
Okay, uploading pictures is like pulling tooth here.

Woodsyi...You have added a lot more traps and acoustic treatments since I have been there.

Dan

You know how it is -- constant fiddling.

I am trying to coordinate Stan and Den. How does 23rd work for you?

bgewaudio · « **Reply #14 on:** 7 Sep 2006, 06:36 pm »

Quote

I would recommend diffusers to go with absorbers. You get clarity without diminishing the output.

I agree, in order to get a good sonic balance, you need to incorporate absorptive and diffusive materials, I think you have accomplished this very well.

BTW, the diffuser is the back panel correct?

woodsyi · « **Reply #15 on:** 7 Sep 2006, 06:46 pm »

Quote from: bgewaudio on 7 Sep 2006, 06:36 pm

BTW, the diffuser is the back panel correct?

Yes, Underneath the cover are the wells.

bgewaudio · « **Reply #16 on:** 7 Sep 2006, 07:33 pm »

Quote

Yes, Underneath the cover are the wells

Ok, so, more or less an abfusor than anything, unless this covering is just a transparent fabric.

woodsyi · « **Reply #17 on:** 7 Sep 2006, 07:41 pm »

Quote from: bgewaudio on 7 Sep 2006, 07:33 pm

Ok, so, more or less an abfusor than anything, unless this covering is just a transparent fabric.

I believe it is a transparent Guilford of Maine fabric. Here is the pdf file describing the panel.
http://www.srlaudio.com/acoustic_images/SRL%20Diffuser%20Panel%20Description.pdf

woodsyi · « **Reply #18 on:** 25 Sep 2006, 02:31 pm »

This is a follow up from my initial report. I am really liking the sound of my room right now. Now I understand what it means to have more air -- each note has more definition and coherence but lingers just a little more to give that phatness to the music. The whole reverberant harmonics (that you can only hear when interfering standing waves get chopped down) make music come alive like it's real. I tested it out by taking down the diffusor and listening. Without it, the notes fall flat and even the soundstage depth collapses. I am sure that I have somehow hit on a good combination of diffusors and absorbers to get this balance in my room. I for sure know that absorbers alone didn't do it and I would not think the diffusor alone without the absorbers would do it. I just lucked into a fortuitous combination that is doing wonders to my room like somehow my fairy godmother came by and waved her wand and sprinkled fairy dust in the room.

I hope midnight never comes. If it's a dream, don't anybody wake me up.

srlaudio · « **Reply #19 on:** 25 Sep 2006, 04:27 pm »

It is great to hear that you are liking the diffusor. We are hearing similar comments from a top recording engineer here in Nashville that has been mixing in the control room we treated at Streeterville Music. He is the engineer for the Nashville Symphony recordings and numerous other projects. He says the same sort of things as you, but adds that he can mix comfortably for a much longer period and the the mixes hold up when he plays them at other places. The studio musicians also like to be in this control room. We are putting pricing up on our site this week and encourage anyone to give us a call. Thanks Woodsyi for being a pioneer in this arena.