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Message started by timstar on 05/26/22 at 00:26:32

Title: Room treatment
Post by timstar on 05/26/22 at 00:26:32

I recently hired Dennis from Acoustic Fields. Has anyone heard of him, liked or disliked his service?

Title: Re: Room treatment
Post by BicycleJoe on 05/26/22 at 02:29:47

I have an appointment for a free consultation coming up next month while I do my own research. Steve has three white papers on room treatment †theory, layout, diffusion, absorption etc gave me some idea, he ahared some formulas

Room Treatments Where do I start?
An introduction and overview of room treatments.

Optimal Listening Room dimensions
You could be sitting in a potentially perfect room and not know it.

How to setup a room without treatment
Another must read for anyone setting up a dedicated or semi-dedicated room.

Title: Re: Room treatment
Post by GroovySauce on 05/26/22 at 13:21:43

I briefly spoke with Dennis when I was buying acoustic foam from him. He is very direct and to the point. He was excited when we found a way for me to spend less money (spend less money with him.) After our call my take away is he really wants people to have great sound.

His foam is fantastic! I replaced 703 DIY panels with his foam and it was as, or more dramatic than putting the 703 panels in.

My brother has his diaphragmatic absorbers and they are incredible. I'm adding them to my system in the future.

Title: Re: Room treatment
Post by BicycleJoe on 06/06/22 at 23:50:15

Groovey Sauce tomorrow I'm going to talk to Dennis for the 15 minute.
I'm not ready to buy but I'm leaning towards using his acoustic foam for my 90 inch iving room window recessed with a 13 inch shelf. That's my first target but I want to do a little research. I really like Geno's panels but I already spoke with the place in New Mexico that makes them.They're having shipping problems right now. I need be able to pull them back to the side for sunlight and fresh air. I think on something that large a few diffusers on parts of it too. That's something I'm gonna ask Dennis.

Title: Re: Room treatment
Post by GroovySauce on 06/07/22 at 11:17:49

BicycleJoe, Let us know what he suggests.

I'm recommending the Acoustic Fields foam. It is so much better than 703.

Title: Re: Room treatment
Post by BicycleJoe on 06/11/22 at 19:37:31

@GroovySauce Took me a minute to go through all the information that Dennis shared with me but it comes down to him recommending his ACDA-10/12 Activated Carbon Diaphragmatic Absorber treatment because of low frequency. He shared that the foam is good for mid and high frequencies, but in a room like mine I need to worry about booming low frequencies. The day after we talked he created a new video that summarizes the information he shared. All this is for the room's front end.

Title: Re: Room treatment
Post by jec3504 on 06/21/22 at 18:15:49

Watched a video of Dennis talking about using only vertical diffusers on the back wall these days. My fiberglass ceiling tiles give me about 7.5' clearance in my room. With that low ceiling would using horizontal on the top or bottom part of the front wall be beneficial.

Planed on using 703 DIY panels on the back wall and to address the rest the absorption issues. Almost have the room empty to start..

Using the Acoustic Fields foam would put a big dent into my budget. Guess I'm sticking with the 703. The best I can do for now.

With the your front wall diffused Nigel does it affect your speaker placement? With a focus on soundstage boundaries? Moving speakers back and forth increase or decrease the benefits using the diffusers?

Thanks, Joseph

Title: Re: Room treatment
Post by BicycleJoe on 06/21/22 at 23:46:17

Dennis was real easy to talk to, he is more than opinionated.He is an authority and he knows his science. But to break it down to simple terms he recommends having a plan with a beginning, a middle. and an end where are you going to start what is your second area of concerns and what do you need to dostep by step. If you work in precise areas with a goal you know what to do. Where you want to go. What's your biggest problem area and what is the solution or the different solutions to consider. I'd have trouble raising my arms in your room, my biggest problem is the 90 inch three bay window in the front of my room. He was not afraid to say such and such is a waste of money, he clearly states that most people selling product and giving advice have never actually done a proper room but are educated in theory not practice.

Title: Re: Room treatment
Post by jec3504 on 06/22/22 at 01:12:13

Hi BicycleJoe,

I'm 6' tall and can't raise my arms all the way up in my room. Have a plan , did a little home work last night. Found the areas that needed to be addressed with absorption. Rubbermaid 6' lockers filled with blankets and quilts moved about in the room. Have the room empty almost and was able to move my speakers into a new location. My plans started 2 years ago when I painted this room 36'x20' with some little out coves. Painted a lot of empty rooms in my day to realize this would be fantastic room for a HIFI system. Don't have any windows to worry about. Asbestos tile with few coats of paint must help with reflection.

Front wall diffusion: My thinking it's going adjust the front boundary. Plan is doing a whole wall buildout. My son's been helping and wants to get his hands dirty so win win for sure. So far we are all very happy with the direction it's going. Been out voted so a 70" TV will be living on that wall. So that is one problem to overcome.

All in all back in the day people used curtains and drapes in the rooms with artsy tapestries hanging on the walls . 1973 sounded real good. Now that I'm aware of where that sound came from things are looking bright. lol



Title: Re: Room treatment
Post by kulafu on 06/29/22 at 13:48:36

I had a chat with Dennis yesterday.  My problem frequencies ranged from 48Hz to 215Hz (48Hz at 1300% over flat, 51Hz at 900Hz and a dip of 72Hz under flat.  This is with room dimensions of 11X9X23 and use of 12in or 15 Altec coax drivers.  He recommended use of Carbon Absorption Panels to address 125Hz and below.  I ran out of time to discuss alternatives such as Acoustic Field Foam that GS recommended.  Or use different low frequency drivers.....Certainly, the investment of 12 of these Carbon Absorption Panels is way out of my budget (provide an 80% solution).  I could incrementally build up but even then, I would have to consider the cost benefit of these vs the acoustic foams and use different drivers.  For those of have used the room analysis, it would be interesting to know if your LF drivers and/or room dimensions drove the recommendation from Dennis.  My length was fine but the width and height were problematic.  It might be worth building a shed with the ideal dimensions rather than investing on acoustic panels.  Bottom line, with the information that I got from Dennis was hugely beneficial along with his videos and literature.  I can weigh my options and go from there.  This is what makes this so much fun!

Title: Re: Room treatment
Post by GroovySauce on 06/29/22 at 14:32:48

I highly recommend Acoustic Fields foam. The foam is for mid and high frequencies.

According to Dennis stacking the foam 3+ sheets thick will start to manage lower frequencies. He offers a product for the ceilingóCPA Ceiling Perforated Absorber that looks like he took a sheet of peg board and stacked 3 pieces of foam on it. If there is peg board between the layers of foam I do not know. Stated absorption is down to 65hz.

If you are handy you might try making a similar design for managing upper bass.

Iím moving into a new home. The room Iím going to use for the stereo is 20x40x8 with a ďlowĒ vaulted ceiling.

Iím going to be adding ~20 of the Carbon Panels. Dennis will be getting back to me next week with a plan.

Bass is some powerful stuff! Car stereos 100ís of feet away can be heard thumping inside a house.

The room ďseesĒ energy. Dimensions drive the treatment more than speaker size. If there is a +12db peak at 40hz I donít think it matters if it was generated by 1x 12Ē, 4x 6" or 4x 15Ē drivers.

He never said anything about 8x 15Ē drivers. If I had a 12x16x8 room he might have mentioned something about too many drivers?

In a shed you will need to manage the low frequencies. What about noise reduction from outside? If going the shed route spray foam insulation is the way to go. In your current home Retrofoam injection insulation will lower outside noise transmission and give better insulation, win win!

Joseph, Consider building a rig with absorption that is easy to move. Place it in front of the TV when not in use.

Title: Re: Room treatment
Post by kulafu on 06/29/22 at 16:53:14

Thanks for that!  That is a lot of Carbon panels for your new listening room.  Your explanation of LF drivers vs room dimension makes sense to me.  Now it is a matter of Carbon panels or multiple layers of Acoustic Foam to address the lower frequencies!  I believe you mentioned that you used 703's before.  Qualitatively, is the performance benefit of the acoustic foam worth the extra cost?  Thanks again!

Title: Re: Room treatment
Post by GroovySauce on 06/30/22 at 00:07:06

Bob, Yes itís a ton of absorption! :D (actually 2 tons.) They weigh 200 lbs each!

I did and still do have DIY 703 based absorbers in my room.

Often people will comment that when too much treatment is used the room starts to sound dead and dark. That is the sound of 703.

I slowly added the DIY 703 panels. 2-4 at at time. I got to a point where the sound stopped getting better and started to notice the limitations of the treatment.

Removing 4 of the DIY 703 and replacing them with larger 25x72" the room took a large jump in sonics. The dead and dark that was creeping in was gone. Subtle nuances came out in the mid and highs. The depth of detail and information †is spectacular.

Iím very excited to get rid of all the 703 and use exclusively Acoustic Fields Foam.

4 Carbon panels might provide significant improvement. Add in an order of the foam and you might have your socks knocked off! ? Treating the first reflection points and a bit of LF absorption should be really sweet.

Due to supply chain issues the DIY foam is only available in XL sheets 55x75Ē. If you are comfortable with DIY. That would be the cheapest option.

If you buy the Foam Frame Panel they are spendy.

If possible go with Acoustics Fields Foam. It is far superior to 703. If budget is an issue I would suggest wait and getting the foam when finances allow it.

Title: Re: Room treatment
Post by Same Old DD on 06/30/22 at 04:39:40

Interesting, Groovy.
I have removed three of my DIY panels as well. I had eight once I kludged them all together. Plus two round face corner stacks of 705.
Corner stacks stay for now.

I was nearing conniption at first because of two window walls with which to contend and trying to manage bridling that some. I put too much absorption in my room at first.
My settled listening showed that I had gone a little overboard with the materials at first.

I have kind of found myself within the Grimani idea set that you should have an asymmetrical room and I already had that in spades. Learning what to tame has been the lesson I had to attend.

Things are better now and I just messed with it all again, but it's coming together.
Together enough that I can focus on getting my cables in better shape next.

Still, I want to try some of the Acoustic Fields Foam!

Title: Re: Room treatment
Post by GroovySauce on 06/30/22 at 12:35:41

DD, What did you observe when you had too much absorption?

BicycleJoe, Have you come up with a plan?

703 does work for increasing resolution and reducing reverb time. If the Acoustic Fields Foam is out of the question the 703 panels are worth it. It's a fine line with the 703 until it starts to mess with the sound.

When setting up in an asymmetrical room it seems like a crap shoot. Some people have really good results and others not so good. Some folks recommend setting up in an asymmetrical room.

When I had a symmetrical room I had the best sound stage I've ever experienced. Currently in an asymmetrical room the sound stage shifts with volume level. The sound stage is more expansive on one side than the other. It's also out of body experience good! If only perfection was the goal then there would be no happiness.

The challenge is that there is no perfect room. Everything is a trade off. Even if you have control of 100% of the design, dimensions and treatment it is not going to be perfect. There are trade offs.

Title: Re: Room treatment
Post by kulafu on 06/30/22 at 12:37:31

Thanks!  Dennis did mention that these were heavy!  As always, your sound advice is helping me make the right decision.  Acoustic Fields foam/DIY it is!

Title: Re: Room treatment
Post by Same Old DD on 06/30/22 at 13:21:39

Groovy, I'm still working on things.
You know how we all try to describe that air between instruments and how we actually listen to the "quiet" as much as the sound. The quiet was beginning to feel wrong.
Too much fluff was like that feeling you get when you're on an airplane and you can still hear fine, you think, but then you swallow and things open up.
It sounded like I needed to swallow.

Even in small rooms, I believe there still needs to be a degree of ambience. The speakers can't do it all. My mind felt like my ears were lying to me when I had too much fluff in there.

Title: Re: Room treatment
Post by jec3504 on 06/30/22 at 16:32:48

Even in small rooms, I believe there still needs to be a degree of ambience.

Good point DD, great discussion.

Thanks all

Title: Re: Room treatment
Post by GroovySauce on 07/04/22 at 21:03:50

Bob, Iím looking forward to hearing about your project, please update us.

DD, Very well said. Similar experience after I installed too many 703 panels.

One thing that makes a great room is that it feels pleasant to be in it. Some home theater demo rooms feel wrong when you walk in.

The plans have changed for my new listening room. The room Iím going to use for the stereo is much smaller than I was told. Itís actually 19x27x8-10í vaulted ceiling goes to 10 foot in the center.

Dennis worked up a treatment plan for me. Tomorrow we will complete it. Then I need to wait a few months. Glad itís not as long as the Decware waitlist!

Title: Re: Room treatment
Post by Tony on 07/05/22 at 00:49:06

Hey GS, Happy Fourth!

Does the vaulted ceiling tend to be problematic or offer some room treatment benefits?  After meeting with Dennis, I would love to see the plans you draw up for the room.  Please post if you can.


Title: Re: Room treatment
Post by GroovySauce on 07/05/22 at 22:32:20

Tony, Thank you!

I asked about the vaulted ceiling. He said it didn't change much. It will give me a little more room when hanging the overhead treatment which will be nice.

He didnít provide a drawing, I also didnít ask. Once I have the treatment he will instruct me where to place it. My guess is it will be 2 QDA-17 + 4 ACDA-10 on the front wall. 2 QDA-17 + 2 ACDA-10 on the rear wall. 7 CP on each side focusing placement closer to the front wall.

6 - ACDA-10, †Front / Rear wall

4 - QDA-17,††Front / Rear walls

14 - Carbon Panels, Sidewalls

3 - CPA,††Ceiling

A quote from Dennis. ďThis room will have the resolution of a near field set up with a room that sounds twice as large as its physical dimensions.Ē On the phone he said that with the diffusion itís going to be close to the resolution of a mastering room.

I'm going to have non-expanding foam insulation injected into the walls and ceiling of my home. It will increase the R value and make the room / house more quiet from outside noise. This is my doing, not from Dennis.

Iím very excited to get the room setup! Iíve been dreaming of a room like this for a very long time.

Title: Re: Room treatment
Post by HockessinKid on 07/05/22 at 22:54:45


Congratulations on the new digs. That treatment system will undoubtedly give you a great listening room. Enjoy it!


Title: Re: Room treatment
Post by BicycleJoe on 07/06/22 at 03:15:39

Groovey Sauce asked

BicycleJoe, Have you come up with a plan?

For now just for my front wall and window, diy carbon panels low end and acoustic foam on the windows, when I get my JBL's back from getting the surrounds redone and the crossovers upgraded  I'll be able to start taking measurements for the rest of the room.

Title: Re: Room treatment
Post by GroovySauce on 07/06/22 at 11:57:34

HK, Thank you. The other day I realized it has been over a year of looking for a new home.

BicycleJoe, sounds like a good plan. I bet covering the large window alone will bring a lot of improvement. Taking on the construction of the carbon absorbers is impressive! Looking forward to progress updates.

Title: Re: Room treatment
Post by Tony on 07/06/22 at 17:29:19

GS said:

I realized it has been over a year of looking for a new home

What took so long? First, find a place that has a good room that can become the best listening room ever. Everything else is optional,   bedrooms, kitchens, garage, etc.   [smiley=cool.gif]

Tony (also, congrats)

Title: Re: Room treatment
Post by Same Old DD on 07/06/22 at 18:20:06

Lolling you here, but you have never had a home taken from you by Imminent Domain laws, I would bet.
You may not have more than a couple of months to do everything. Taking a year to find a home seems like normal to me.

In my case, I felt like the insane housing market in our area would be OK. I am selling a home (to the city) and buying one (for the rest of my life).
The insanity of the market should balance out, right? We won't be affected much, right?
Not so.

If I had not had a substantial bit set aside for my retirement (some of which is gone now, invested in a new home), we would be in the same boat as twenty seven other families, six businesses and a church who have been displaced by this latest city project.
We were in the way of progress; it happens. Hey, the city needs the project to go forth!
We made the best of it. We won! We managed to upgrade. Not all will win in this transformation of the city to modern concerns.

Finding a home can be more complicated than you jest.

Title: Re: Room treatment
Post by Same Old DD on 07/06/22 at 18:29:40

Groovy, bless you, Man, and good luck with your new digs!!

After six months, I'm still finding things to spend even more on.
All the BIG stuff was good to go, but replacing a ten year old water softening/treatment system and such is a something (cost as much as a Tori).
Small somethings.

But, we are happy!
Hope you are, too!

Title: Re: Room treatment
Post by GroovySauce on 07/06/22 at 19:52:03

Thank you all for the well wishes!

What took so long? First, find a place that has a good room that can become the best listening room ever. Everything else is optional, † bedrooms, kitchens, garage, etc. † Smiley

Tony, there is a lot of truth in that statement!

I was looking at building an outbuilding and have that be a dedicated music room. The search was more difficult because I had a few other considerations. I ended up with almost everything I wanted. The home has a nice view of the Smoky Mountains, which is appreciated.

Same Old DD, That sounds like a rough experience. Glad it worked out in the end. Yes, the small things do keep ya on your toes.

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