Jeff Hedback designed acoustical panels

mikeeastman · « **on:** 13 Jun 2011, 03:37 am »

I been working with Jeff Hedback to treat my main listening room, 1st he is great to work with very patient and creative. Here are some pics of the acoustic panel he designed for my room in various stages of the build. They still need to be covered except the last one which only needs to be trimmed out.

I used an insulation made from old blue jeans rather than fiberglass, suppose to be slightly better acoustically and a lot nicer to work with.

I still have 4 more to put up but the room already sound much better.

jimbop · « **Reply #1 on:** 14 Jun 2011, 03:51 am »

Is there something specific about the types of wood, as well as the sizes and thickness?

JD

TrungT · « **Reply #2 on:** 14 Jun 2011, 04:06 am »

Mike
Looking good

Jeffrey Hedback · « **Reply #3 on:** 14 Jun 2011, 11:56 am »

A little background on panels, sure. The panels as a system have elements to address the entire spectrum.

They start with a mass loaded vinyl membrane over an airspace. This is a very wide Q membrane LF trap.

Next is a layer of UtraTouch (a 2# version). I find this product to be excellent in the midrange, especially when the sound is from non normal angles of incidence. Mike's quasi-hexagonal room is certainly a good place for that benefit.

The slats contribute what is called amplitude reflection grating: a type of diffusion where you have two amplitudes the reflected energy off the slats and the absorbed energy that passes between. The actual spacing is a strategically random 50/50 pattern. The use of the vert/horiz. arrays is to minimize specular and singularly hot reflections. Spacious is the term I expect Mike to offer when all is up and going. The type of wood was discussed in detail with Mike and he had access to some super cool reclaimed woods that I believe he uses (and very nicely).

The remainder of the system is acoustical fabric of which some is behind the slats and some will be over. Mike is wonderful to work with, a top-notch carpenter. He brought excellent ideas from the design concepts back for my review and very completed the effort with is unique abilities.

mikeeastman · « **Reply #4 on:** 14 Jun 2011, 02:45 pm »

The wood is, Gimbal Oak, Ash, and Mesquite from trees that had died or needed to be removed, that I had cut into planks 3/4" thick by a local saw mill. I also used MDF on some the panel that will be covered. I couldn't wait till I had all panels up to listen to the results WOW! I could feel the panel in back of and to the side of my listening position, like I was in a cocoon of soft sound with the staging very sharp and detailed. I expected it to improve the sound in my room but not to this degree, Jeff your a GIENUS!

mikeeastman · « **Reply #5 on:** 14 Jun 2011, 04:33 pm »

Got two more panels up this morning, only two more to go. They will have cut outs in fabric that covers them like this, showing the slats underneath.

TRADERXFAN · « **Reply #6 on:** 14 Jun 2011, 06:01 pm »

Quote from: Jeffrey Hedback on 14 Jun 2011, 11:56 am

A little background on panels, sure. The panels as a system have elements to address the entire spectrum.

They start with a mass loaded vinyl membrane over an airspace. This is a very wide Q membrane LF trap.

Next is a layer of UtraTouch (a 2# version). I find this product to be excellent in the midrange, especially when the sound is from non normal angles of incidence. Mike's quasi-hexagonal room is certainly a good place for that benefit.

The slats contribute what is called amplitude reflection grating: a type of diffusion where you have two amplitudes the reflected energy off the slats and the absorbed energy that passes between. The actual spacing is a strategically random 50/50 pattern. The use of the vert/horiz. arrays is to minimize specular and singularly hot reflections. Spacious is the term I expect Mike to offer when all is up and going. The type of wood was discussed in detail with Mike and he had access to some super cool reclaimed woods that I believe he uses (and very nicely).

The remainder of the system is acoustical fabric of which some is behind the slats and some will be over. Mike is wonderful to work with, a top-notch carpenter. He brought excellent ideas from the design concepts back for my review and very completed the effort with is unique abilities.

Very cool. I like the use of the mass loaded vinyl air pocket! Much simpler to make than a wood panel trap, but I don't think it will extend as low.

Will there be more treatments for the low end? or not in the purview?

ted_b · « **Reply #7 on:** 14 Jun 2011, 08:14 pm »

Jeff designed these for my room, and then we had my local carpenter (Doug Carpenter, yes that's his name

) build them. The "sails" on the side walls were also designed by Jeff, but custom built. Also in these pics are floor to ceiling front corner traps Jeff designed, and unseen is MATS, a 400 lb resonating floating wall that hangs behind the video screen.

JEFF IS THE BEST!!

Nyal Mellor · « **Reply #8 on:** 14 Jun 2011, 08:43 pm »

Very cool!

The arrangement of the slats of woods over the top is bit like a DIY RPG BAD panel, a combination absorber and diffusor. Great for use at side wall and back wall locations. Good work Jeff and the carpenter!

mikeeastman · « **Reply #9 on:** 15 Jun 2011, 03:29 am »

Finally got the last panels up tonight.

jhm731 · « **Reply #10 on:** 16 Jun 2011, 12:37 am »

Where can someone obtain the plans for these panels?

mikeeastman · « **Reply #11 on:** 16 Jun 2011, 01:20 pm »

Contact Jeff, but I believe they are at least some what designed for each specific room as part of his acoustical consult.

Jeffrey Hedback · « **Reply #12 on:** 16 Jun 2011, 01:31 pm »

That is correct Mike and we should mention that your design was driven by data from my remote acoustical room test process.

Rob Babcock · « **Reply #13 on:** 19 Jun 2011, 09:17 pm »

Nice!

Very different looking compared to most panels.

mikeeastman · « **Reply #14 on:** 20 Jun 2011, 02:46 pm »

Got the covers on last night, still need to trim them out and do the cut outs on one panel(last pic). Played some hi rez I just got, last night and WOW! very clean and focused staging. The bass is the tightest it ever been on my system. If you want to transform you room Jeff is the man

They have HWF because she dyed the covers.

Jeffrey Hedback · « **Reply #15 on:** 22 Jun 2011, 03:16 am »

Here is an initial "peak" at the pre/post results. These are spectrogram graphs showing LF resonance. Take note of 1) the reduction modal resonance at ~105hZ, 2) greater "smoothness" across the lf range and 3) the reduction of resonance below 40Hz. There was a shift in listening position (LP) pre to post so the data is not completely 1:1...that said, still fun to review.

Mike already had an expansive and effective ceiling cloud in place before this effort...so the pre measurement really is not that bad. More later...

Rob Babcock · « **Reply #16 on:** 22 Jun 2011, 07:11 am »

Wow, those last ones look even nicer!

mikeeastman · « **Reply #17 on:** 22 Jun 2011, 02:31 pm »

The ceiling cloud was based on a suggestion by Danny at GR research. As a beginner the graph are outside of my understanding, but the room sounds great, now it needs to be re EQed.

McTwins · « **Reply #18 on:** 24 Jun 2011, 10:11 am »

Hi
I absolutely don't see any difference between those two measurements before and after, you haven't taken that resonanse at 38 Hz and at 105 Hz at all.

I think that the difference in measurement is due to differn't mic position. I would like to see a freq response measurement and I bet there is great peaks and deeps in the lower regions.

I really don't belive that those home made diffusors can take low freq below 100 Hz. If one belives that then they don't have the knowledge about room acoustics.
Really, in my opinion, this can't be working as a diffuser. It is not even made as a Schroeder diffuser(Maximum- Length Sequence). Putting fabric over the so called diffuser will degrade the diffusors effect even further.

This is a great example how a diffuser should NOT be constructed and to call it a diffuser is wrong.

Thanks

bpape · « **Reply #19 on:** 24 Jun 2011, 12:35 pm »

It's not the typical diffuser. It's a combination of a limited range absorber with some phase grating.

There is absolutely a difference in intensity between 30 and 50Hz and less of a tail around 100Hz. Yes - it still needs some work but there is definitely a change.

Bryan