Best Acoustic Products for First Reflection Points

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Quote Originally Posted by Mike Lavigne View Post
I have a completely different take on this question.

there are multiple cases to consider. first is driver type. obviously dipoles and horns interact differently with side walls and ceilings than cones.

I think for Ron's question we are speaking about cones mostly.

next is local and global. local is where there is relatively close distance between the speaker and wall, global is where the distance from speaker to wall is farther. and the actual issue is the reflection time (from driver, off the wall, and then to the ear, compared to the direct sound) and whether that reflection will be considered a smear or separate from a smear. this difference will change the type of treatment you choose. the local needs a more aggressive approach with possibly some absorption too. global might then be better with less aggressive treatment to retain more energy.

then there is the issue of speaker cabinet<->side wall resonance. your bass towers will have close proximity with the sidewall and there will be resonance between that sidewall and the bass tower cabinet which will need treatment independent from the 1st reflection treatment. sound bouncing from the cabinet to a flat wall surface and back again; creating distortion. this situation likely needs some sort of aggressive diffusion to break up that resonance.

lastly there is the balance between diffusion and absorption on the sidewall, and the balance between diffusion and just surface texture. surface texture will knock down reflective hash without changing tonality. I use cloth thumbtacked to walls as surface texture. it can be particular paint, or wall paper. I have built in diffusion in my room, and found I needed to treat the surfaces of that diffusion. eventually I had to place a towel over the meter bridge on my Studer A-820. I put cloth treatments on the ceiling 6-7 feet behind my listening position.

it all matters.

until you start to control the worst of your 'wall related issues', you won't even know about the next level of issues (that 1st refection hash covers the second reflection issues). and until you fix those, the deeper ones are not evident, and so on, and so on, and so on. like doors that get revealed as doors, once you remove the wall you didn't know was there. and in my case I needed a stack of three RPG Skylines in the center wall behind the speakers to begin with for proper center focus, but after I properly controlled first reflections, that Skyline Stack became a detriment messing up center focus, so I got rid of it. turned out it had been a band aid on a larger problem. so progress is not always linear.

and once the first reflection issues are somewhat treated, you need to keep going into places that your intuition tells you are not a factor. forget logic, keep chasing the reference in your head until you do things that your ears tell you don't matter. ignore your eyes and brain. they are not you peel layer after layer of the onion. big speakers, lots of driver surface, lots of energy, problems where you least expect it.

until you get the room controlled, speaker set-up will be provisional. I was in my room for 10 years when my speaker designer visited and fine tuned everything. then 18 months later once I fixed my room, I had to start over. and it was night and day better....with just me doing it.

you spend high 6 figures on gear; that gear deserves a relentless approach to getting the room fully out of the way of the musical message.

sorry to blather on and on, but this subject is very passionate for me. YMMV and all that.

good luck with this stuff.

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