Thread: Corners, Side Walls and Openings

I'm finally getting closer to setting up my system in the new house. Before I do anything I'm going through Getting Better Sound again. On this second reading I have some to suspect I lack some of the basic knowledge that Mr. Smith assumes. I posted some pictures of the room a while back.

My room is very long, and I am planning to set up across the short dimension. This places the side walls far enough away that the mirror trick for first reflections is kind of meaningless. Or is it? With the Magnepan 1.7i speakers out from the wall behind them the distance to the listener can't be more than nine or ten feet. To the right the side wall is 11 feet, to the left 15 feet. Yes, that is very much non-symetric, but is it likely to matter so much at such distances?

Corners... the corners for the wall behind the listener are equally far away. The one 15 feet to the left includes the front door to the house, so any treatments would have to be very mobile. As for the corners of the wall behind the speakers... there are no corners. On the 15 foot side the back wall just keeps on going down a hallway, after it passes a three and a half foot opening to another room. On the 11 foot side there is a full side wall but another three and a half foot opening at the end of the back wall.

If someone can convey what everyone knows about way-far-away side walls and missing corners it will be appreciated.

Thanks!

RH in CT

Thanks for the pointers. The Toole book should be here Friday. 8-)

Symmetry is really important in the world of acoustics. Make sure to focus on the correct sitting location. Then work on the speaker placement. And, don’t overdo acoustical panels.

In addition to the books you are reading, reach out to the folks at GIK Acoustics. They will provide suggestions on how to acoustically treat your room (I have no association with GIK).

Good luck and keep us posted!

I hear you about symmetry. One of the issues with the room is the bay window. My current intention is to start with the listening spot centered in front of it, facing away. Just about every other arrangement I've thought of makes it the most impossibly unsymmetrical point possible, so instead I'm hoping to take advantage of it to keep the listening point away from the wall behind it. But this is just blind guesswork. I do expect that some sort of curtain will cover it for acoustic reasons without factoring it out completely. Not that my expectations mean much at this point.

I have Audio Tools. The basic product is $20.
AudioTools - dB, Sound & Audio on the App Store

Before that I played with a free app.
Audio Spectrum Analyzer dB RTA on the App Store

I won't be using DSP for the system in question and I am fine with that. When I bought my electronics I chose a unit that doesn't provide it, and has no provision to add it. The NAD Master Series M32 Direct Digital Amplifier with the DD BluOS module is an integrated amp that is entirely digital inside. The power amp stage IS the DAC stage. Yes, I understand that this goes against the fundamental audiophile lifestyle of perpetual upgrades, but I just want to listen to music.

I am at the stage of trying to figure out what rugs, bookcases, chairs, tables, and so forth will be in the room. I've got bookcases that have to go somewhere, and while most will go in other rooms at least a couple have to be in the room with my stereo. I bought the Floyd Toole book, but I haven't had time to read it yet.

I know Jim Smith rails against putting the electronics between the speakers, but all I have is the one integrated amp and an optical disk player. I am wondering if I removed the top two layers of the stand and put the shorter disk player on top, all of it will all be in the bottom 18 inches or so. When the speaker panels are over five feet tall... maybe that 18" of interference would be tolerable? Then again, since the Magnepans radiate to the rear as much as the front, it could be even worse.

For now I have to get reading that book and get up to speed on the basics.

(Side note... the 5.1 system in another room will get minimal accommodating toward perfection. The Yamaha receiver there comes with a little microphone to let it do some balancing, but otherwise... it is just for the TV.)

IME equipment between speakers will have a minimal if any effect on sound at the sweet spot. However, the smaller the room the more of a difference it will make. removing or moving 1 piece of gear in between will have no significant effect.