I didn’t see a lot of information about line source, dipole type speakers on the Acoustic Fields site or on the You Tube video area.
I own Martin Logan Summits and was wondering what special issues diploe speakers add to the design of the room treatments?
Most forums will say that you need absorption
in the front and sides, and diffusion in the back.
These type speakers are not supposed to send much sound to the side walls and thus side wall deflection may not be as big of deal as with traditional cone type speakers. I’m sure room size would make a difference here though.
Do we want to absorb the back wave?
How far away from the back wall should they be if we are absorbing the back wave?
Can they be placed closer to the back wall without negatively effecting the sound stage?
Any comments on what type of room treatment types/placement you are using for these type of speakers would be appreciated!
You will need to look at your room size especially the room width to determine treatment. Absorption for dipoles for sides and front walls is a popular treatment. I have also seen absorption for the side walls and diffusion on the front wall used for dipoles.
Here is a partial post off of the Martin Logan owners site from a well respected member of the “club”. He seems to mirror you thoughts that either absorption or diffusion can be used on the front wall, depending upon how far the stats are from the back wall. . . . .
“I have used both absorption and diffusion behind my panels at different times. Here are my thoughts. If you can’t get the panels more than three feet away from the wall, absorption is the way to go. If you can get them four to five feet away, then diffusion is the way to go. Absorption will give you an increase in clarity and precise imaging but flatten the soundstage. Diffusion will give you a wider and deeper soundstage, but imaging won’t be as pinpoint precise. Neither is inherently “better.” They are just different. The acoustic space sounds more natural with diffusion but the crystal clarity and pinpoint imaging with absorption is pretty cool.
Here’s the thing, though. You have to absorb or diffuse the entire back wave of the speaker panel. So you need a panel that is as tall as the speaker panel and is directly behind it on the wall. You also need a panel that can absorb the entire frequency range of the speaker panel, down to about 500 hz., and not just the higher frequencies, for it to be truly effective. This generally means a panel that is about three to four inches in thickness. ” R.
I am trying to “absorb” (pun intended) a lot of the information/videos on your site before I make any decisions/purchases. I have two potential rooms for my two channel system, both have more bad than good, which is another reason why I have hesitated sending in any room measurements for analysis. Are there any products that you can suggest that would be useful in any room size? Would the ACDA -10 and ACDA -12 be used in all situations regardless of room size?
The largest area of unwanted sound pressure within a two channel room is the area found between the speakers and the front wall. Placing low frequency absorption using the ACDA -10 broadband absorption will do two things. First, low frequency management and secondly, middle and high frequency absorption . The face of each ACDA -10 has our foam technology. This allows the unit to absorb from 30 Hz. – 6,300 Hz. Low frequency definition and separation will improve dramatically along with middle and high frequency spectrum balance.
Choosing the right size and volume in a room is critical. Go to this link and fill out the information. I will then compare your room to our data base and look at the unwanted low frequency issues along with their location and strengths within your room. In many cases with these room ratios and volumes, a few feet in difference in any one dimension can make a large difference in the amount of low frequency treatment.