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GIK Room Treatment Questions and Advice for Magnepans


     I submitted the following request form recently to GIK Acoustics for a free room analysis.  I want to apologize from the outset that my information establishing the relevant information is so lengthy and extensive, just for a few questions requesting advice at the end, but I thought it was important that readers were aware of all the facts in order to be able to offer the most relevant, specific and meaningful advice.  I'd also like to thank in advance any and all of you that take the time and effort to read this tome and respond.  I'm very appreciative of any advice you're able to offer.
     Okay, here's what I submitted as answers to the GIK form's questions:

 Room Size (width x length x height)?   16' x 23' x 8'
 Is this a dedicated room?   No 
What model of speakers / sub(s) will be used in this room?   Magnepan 2.7QR main speakers, a Magnepan CC3 center channel speaker and a 4-sub Audio Kinesis DEBRA  bass system positioned in a distributed bass array configuration in the room along with a pair of Infinity rear surround sound speakers mounted in the ceiling at the rear of the room. The room is a living room but is used for both 2-ch audio and 5.4 surround sound for HT. My Magnepan 2.7QR main speakers are 6' tall x 2' wide x 2" deep panels that straddle the 65" hdtv and are each positioned about 4' away from the front 16' wall. These and the CC3 center are bi-pole speakers.
Flooring?   Soft surface wall to wall carpeting. 
Are you able to move the location of your set up within your room if needed?   No 
Placement Restrictions?   I have a 65" plasma wall mounted and centered along the front 16' wall, with the center of the flat screen about 38" from the floor so it's at eye level at my viewing/listening seat centered on the rear 16' wall. The CC3 center ch spkr is mounted on a tv wall mount that places the speaker centered just above and even with the front plane of the 65" plasma hdtv screen. Both the hdtv and CC3 are extended about 32" away from the front 16' wall on their wall mounts. There's a 6' high and 8' long window centered on the left 23' wall that is covered with an equal sized plantation blinds window treatment with 1" horizontal slats.
There are two 5' wide openings to this room, one located along the rear 16' wall just in back and to the left of my listening chair as I'm seated in it (this leads to my home's front door foyer) and the other opening is located along the front of the right 23' wall that begins about 2' away from the front 16' wall (this leads to a large dining room).
There's also a 3' tall x 2' wide mirror hung and centered above my leather listening/viewing chair on the 16' rear wall behind it. I'm willing to remove this if you determine diffusion or absorption panels would function better on the rear wall directly behind my chair. 



     Here's the GIK rep's recommendation I received in response:

"I agree that with Magnepans diffusion of some sort is helpful on the front wall. While I’d love to throw a wall of Gothams up there, it would destroy the budget and leave too much other stuff untreated.
I think we should use the Alpha Series for a majority of the treatment because they provide both diffusion and deep absorption so we can solve both problems simultaneously. Based on what I could gather from your description we can at least treat the corners and front wall behind the speakers. It seems like there’s space behind the TV and center channel so bass treatment back there is helpful too, but I’m pretty sure our budget will limit our ability to do that.
The back wall would also benefit from a similar approach and I would absolutely recommend you remove the mirror from behind your chair.
I think I’ll give you a plan that covers more area that is well over your budget, but you can do some now and some later. That way you have a plan that gives you a more complete room that you can aim for down the road.

Here’s what I recommend for a fairly complete room:
4 -CT Alpha Series Corner Bass Trap with 2D Scattering @ $210.00 two in each front corner stacked for bass treatment and diffusion 5 -244 Bass Trap w/FRT (24”x 48” rectangle) Full Range @ $74.99 on the left wall next to the window to offset the archway on the other side and four mounted evenly across the ceiling. 2 -4A Alpha Series Bass Trap Diffusor/Absorber (Rectangle) with 2D Scattering @ $138.00 on the front wall one behind each speaker for diffusion and absorption 3 -6A Alpha Series Rectangle with 2D Scattering @ $198.00 on the back wall behind your chair for diffusion and bass absorption.
Total for all: $2084.95 plus shipping. It doesn’t address the sidewalls much but with the archway and the window, I don’t know that there’s much other space to treat there anyway." 


     Okay, here are my thoughts and questions for those intrepid souls that made it this far:

1.  I'm not going to purchase all of GIK's recommended room treatments for $2,085. I'd prefer to purchase those treatments that you and I believe will improve my room acoustics the most on a budget of about $1,000 initially with more to be purchased in the near future, after I have a chance to install and evaluate the results of the initial treatments purchased.
     In particular, I don't think any of the following are necessary or will be of benefit in my room: the 4 -CT Alpha Series Corner Bass Trap with 2D Scattering @ $210.00 two in each front corner stacked for bass treatment and diffusion 5 -244 Bass Trap w/FRT (24”x 48” rectangle) Full Range @ $74.99 on the left wall next to the window to offset the archway on the other side and four mounted evenly across the ceiling.  My reasoning is that my AK DEBRA 4-sub distributed bass array system currently provides extremely good bass performance in my room down to about 20 Hz along with the bass blending  very well with my main speakers throughout my entire room with absolutely zero room treatments being currently utilized.  I'm mainly concerned that any added room treatments functioning as a bass trap would only have negative effects on the bass in my room.    

     Does anyone think using treatments that include bass trapping would be of any benefit in a room in which the bass is already considered extremely good?  If so, what benefits would be perceived?


2.  I'm thinking it would be best to use 2D diffusing treatments on both front and back 16' short walls in my room; meaning behind each dipole Magnepan on the front wall, the space above my flat panel hdtv and between my main speakers on the front wall and behind my listening seat that is centered on the rear wall.

     Do you agree that placing a 23" x 45.5" rectangular 4A Alpha Series Bass Trap that also diffuses behind each Magnepan and smaller 2' x 2' square 4A Alpha Series Bass Trap that also diffuses behind my listening chair and above my hdtv and between my main speakers woul be a good solution?

     Or, do you think one of these diffusers would be better behind each Magnepan?
https://www.gikacoustics.com/product/evolution-polyfusor-diffusor-absorber-bass-trap/

https://www.gikacoustics.com/product/gik-acoustics-q7d-diffusor/

    I'd also like to know if you think 2' x 2' square absorption treatments would be best behind my listening seat and possibly above my hdtv like these?

https://www.gikacoustics.com/product/gik-acoustics-242-acoustic-panel/



Thank you for any advice you care to offer,
                     Tim
128x128noble100
larryi
3,714 posts
 
I can't give you any specifics about what to purchase.  However, I can say that I've heard rooms with GIK products in them and they work quite well.

As a general observation, I've heard a lot of rooms that I think are over-treated.  I think that the right approach means taking things slowly, and incrementally.  That approach does not have to be haphazard, and so it might be helpful to get a plan from someone like GIK, with the intention of just implementing a few recommendations first.  I have heard far too many rooms that have become lifeless sounding from over treatment, so going slow helps to prevent this from happening.  

I think you should start with the front wall and the part of the room behind the speaker.  Maggies and other bi-directional speakers are helped by the back reflections, so it makes sense not to kill that sound with absorption, and instead, rely on diffusion to spread that reflected sound evenly.  Bass trapping on one side of the room (traps in both corners of the same side) is also helpful.

For the wall behind the speakers and for the side walls, it might be enough just to use some decorative fabric wall hangings/carpets.  One of the better rooms I heard was basically a concrete bunker, but the walls were treated very lightly with tapestries; this was enough.  Other nice rooms had no real treatment, but, a lot of book cases and other furnishings to break up the flat surfaces on the side and back walls.

Good luck on your venture.
three_easy_payments's avatar
three_easy_payments
2,097 posts
 
I agree with @larryi ’s comments about approaching room treatments incrementally. Starting with corners and spaces behind the speakers and then adding slowly as needed. I use mainly GIK products (mix of absorption and diffusion) myself in a fairly lively room with glass windows along a long wall, 10 ft ceilings, and hardwood floors (with large area rug in front of speakers). I recently added 2 ASC Tube Traps at first sidewall reflections mid-way between the speakers and the listening position and this really took things to the next level. there is a lot to be said for a room treatment that is easily moved and can be rotated 360 degrees to dial in the perfect mix of absorption/diffusion for your room and listening position. I got the Tube Traps used for half of new retail. I think I now have the room dialed in nicely without overtreating...a perfectly balanced and lively room free of annoying flutter and bass boom.
ditusa's avatar
ditusa
1,681 posts
 
8' ceiling hight is bad 10'12'14' is good. bass waves below 100hz are room length dependent 23' 40hz wave is about 26ft it cant fit without standing.or bass traping.good room ratio is 17'W -10'H-27'L www.acousticfields .com dennis foley.
noble100's avatar
noble100 OP
2,419 posts
 
Hello brownsfan,

Browns looked good pounding the Jets. And yes, I did buy your old house and yes, I did find that hidden dungeon room you built in the basement. Talk about room treatments, that thing is soundproof! It’s now my kids’ new playroom, thanks.
My system doesn’t really have any major issues, overall it sounds very good. I’m mainly interested in achieving a very palpable, 3D presentation that makes it seem like the musicians are in the room or I’ve been transported to the musical venue. I currently only have this experience on some select very good recordings.

I’m using an 18 TB NAS containing about 20K albums, about half are FLAC ripped CD files and half are hi-rez FLAC and WAV files that range from 24bit/96KHz to DSD and I’m using a Lumin D2 to stream these files. I was thinking I have a decent enough system and enough well recorded music recorded at a high enough resolution that the ’you’re in the room’ quality playback should  be a more common occurrence.
My main goal for investing in improving my room’s acoustics is to have more of my music collection provide this ’in the room’ perception. I’m thinking better room acoustics is likely a good method of achieving this. I really enjoy the somewhat elusive experience of a solid and stable 3D soundstage where everything seems and sounds so dynamic, palpable, immediate and real.


Hello larryi and tep,

I agree with you both about approaching room treatments incrementally along with not wanting to over dampen the room through absorption. I’ve been learning that utilizing panels that diffuse or scatter the midrange and treble frequencies while also absorbing the bass below a specified frequency may be the best solution for my dipole speakers and room.
The bass in my room, thanks to deploying four 10" subs in a distributed bass array system, is currently extremely good and I believe there’s still no need for any bass traps in my room. 
     But I understand that excessive upper bass in a room can mask and negatively effect the important midrange frequencies. I don't hear any excessive bass at any frequencies.  However, I've also never ran a spectrum analysis in my room and it's technically possible there's some bass issues effecting higher frequencies that I'm not even aware of.  Therefore, I'm hoping a bit of upper bass trapping built-in to some of the newer GIK acoustic diffusor panels won't change my perception that the bass is extremely good in my system/room but, if there are issues, this damping may even improve the sound quality overall.  I'm doubtful but realize sometimes you just don't know what you don't know. I'll just call 'em like I hear 'em.
     So, I’m currently planning on starting with the following:
Two -4A Alpha Series Bass Trap Diffusor/Absorber )33"x48.5"x2"Rectangle) with 2D Scattering on the front wall one behind each main speaker for diffusion and absorption.
Six--4A Alpha Series Bass Trap Diffusor/Absorber (24"x24"x2" Square) with 2D Scattering, 3 on the front wall above my tv and between my main speakers and 3 on the back wall directly behind my listening chair, all for diffusion and absorption.

I think this is a good targeted quantity to begin with. I’ll audition the results with these and proceed from there.


Thanks you guys,
Tim
three_easy_payments's avatar
three_easy_payments
2,097 posts
 
yep, according to the guys at Arqen Sonic here are the Three Golden Rules for treating small (e.g., domestic sized) rooms:

  1. Add broadband bass traps to as many corners as feasible, including the wall-ceiling corners.
  2. Add mid/high frequency absorption at the first reflection points on the sidewalls and ceiling.
  3. To prevent flutter/slap echo, add some mid/high frequency absorption and/or diffusion to any large areas of bare parallel surfaces. E.g., parallel walls, parallel ceiling and floor.

This my basic approach.  Haven't gotten to the ceiling yet.

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