I have spent about a year and half playing around with the positioning of my Maggie 20.7’ in my living room and the acoustical treatments that have seemed to help the sound-stage the best. I am going to share what I have learned through an iterative process of trying a variety of acoustic treatment strategies. I hope other folks will share their experience and pictures of how they treat their room with a dipole/planar speaker that creates a wave form like the Maggies. I have found that the treatment that works for my Magnapan 20.7’s is much different than the treatments I used with my previous dynamic cone speakers. This makes sense as the wave form is much different with these speakers.
I have found that at least in my room there are three basic rules with respect to treating the Maggies:
Rule 1: Treat any bass issue (this is probably also true for dynamic/cone speakers as well). The need to treat bass nodes and bass buildup will depend upon the size of your room and if you are using subs. This was the costliest treatment endeavor for me as I have found that I needed to use a variety of tube traps and sub traps to clean up the bass. If I could have a room that just had tube traps all around the perimeter I would, but I don’t want my living room with a perimeter of columns around the room. The tube traps can provide both bass absorption and diffusion of the mid-range and treble all in one solution.
Rule 2: Diffuse the back wave of the treble and mid panels before they hit the side and/or front wall. Depending upon the orientation of your speaker, your mid and treble wave form is going to hit either the side wall or the front wall or both. Find a way to diffuse these wave forms before you have a second poorly timed wave form coming bouncing of the front wall and hitting your face at the wrong time. This can be a relatively cheap endeavor depending upon your room and your desire.
Rule 3: Diffuse the 1st front wave of the treble and mids behind your head. Find a way to diffuse the front wave launch after it passes your head. You want to avoid having the front wave bounce of the back wall undiffused.
Here is how I addressed these rules in my listening area. My listening area is my living room/kitchen great room that is 18 ft wide by 30 ft long by 8 ft high. It is not a dedicate listening room so I need to have a modular set up as much as possible so I can remove treatments when needed. If I had a dedicated listening room I would go with various tube traps around the perimeter of the room.
Background Listening Mode
The following is a picture of my living room during background listening mode when I am having non-audiophile guests over. Yes, look at all that horrendous reflecting glass. Fortunately, the speaker’s orientation in ideal listening mode is not directed to the glass but the sidewalls. Also, there are relatively easy ways to add diffusion of the back wave before it can get to the glass.
I try to make the place look as normal as possible with speakers the size of Lebron James. Not saying it looks normal, but it is the best I can do. My two subs act as coffee tables to the chairs that hide most of the stereo rack. In this position the speakers are about 6 ft from the front wall and the side treble panels are about 6 inches from the sidewall. The soundstage is wide but not as deep as it could be, and the soundstage is not as precise as when I have my ideal serious listening set up.
All the acoustic treatments are buried behind the speakers and stacked in the corners to treat bass issues and diffuse the back wave of the treble and midrange at least partially. I am getting rid of my murphy bed so I can put some of this stuff in a closet in the near future.
This is what the back wall looks like during background listening mode. My kitchen and back wall have a lot of hard surfaces that can reflect the back-wave sound to my ideal listening position.
Serious Listening Mode:
It takes me about 5 minutes to transform the room from normal mode to serious listening mode. I move the speakers about 10 ft from the front wall with the treble ribbon on the outside. The treble panel sits about 3 ft from the side wall. My listening chair is about 11 ft from each speaker. I move the subs forward to the sides of the speakers and lift them up on the subtraps. I also move the chairs from the front of the stereo to the side wall. My listening chair sits about 10 ft from the back wall or about 2/3 of the way into the room. The treble panel is directed to go about 3 inches outside of each ear. I move the chairs lift the chair up on concrete blocks so I can have my ears at the middle of the height of the panels.
I reorganize and reorient the treatment tools into their ideal spots behind the speakers to deal with Rules #1 treat the bass, and Rule #2 diffuse the mid and treble back wave. Below I will show a variety of configurations behind the speakers.
1(a) Concrete Forming Tubes for diffusing the back wave
The speakers are oriented such that the treble panel hits the sidewall and the mid-range panel is directed to the two tube traps in the corner. The corner traps are oriented, so the diffusion portion of the trap is directed towards the Maggie panels. One of the tube traps is placed on the side wall oriented to the side of the sub to handle a node formed by the sub on the sidewall.
Ironically, the cheap concrete forming tubes painted black and filled with insulation to prevent any tube ringing are the most flexible of the diffusion tools for the mid and treble diffusion. They can be moved easily to shape the sound and diffusion from the back of the Maggie panel. I can set them up so they cover the treble and mid-range waves before they hit the glass. They work just as well as the diffusion products that follow. They just kind of look crappy but they do look good buried in a closet or behind a panel.
1(b) Using GIK PolyFuser for Diffusing the Back Wave
The GIK PolyFuser can be mounted on the wall or I just set it on a couple of tubes to lift it to the correct height. It also can fit on the alcove next a couple of feet inside the tube trap to provide some diffusion in front of the glass. I find my ideal set up so far uses a combination of the Polyfuser on the alcove and the concrete forming tubes behind the speaker near the wall.
(2) GIK Gridfuser for diffusing the back wave
The GIK Gridfusers are super lightweight and are easy to move. They also can be painted with water-based paints. GIK has fancier looking diffusers. I tried these because I knew they are easy to move and can be placed in a variety of diffusion areas. You could literally tape these to a wall. They are actually designed to fit in ceiling grids.
(3)DECWARE Diffusers for diffusing the back wave
These are heavy wood diffusers that can be stained or painted. They look the best out of all the diffusing tools. Ideally, they would be mounted on the wall at a height the matched the panels mid spot. I prefer to avoid a permanent attachment to the wall. That is why I prefer the concrete forming tubes in this location.
How to Address Rule 3: Using Concrete Forming Tubes to Address the Front Wave Bouncing off the Back Wall
Yeah. I know this looks like a gong show. I don’t go this extreme often. I don’t have a dedicated listening room so I need to find a quick way to treat the back wall without taking up a bunch of space, which leads to using concrete forming tubes. I can easily move them so they can form a cocoon of diffusion to protect my listening spot from straight line reflections. The forming tubes can nest neatly within each other so I can store them away relatively easily.
Notice the concrete blocks lifting the chair so my ears are at the mid-level panel of the speakers. Try this folk, it will surprise you.
Nesting 4 of the tubes for easy storage.
This is another way of treating the back-wall wave of mids and treble. The nested concrete tubes are easier to set up and store away than this set up.