RE: I start out measuring the room. then calculate fractions of room and skip bad ones

Aside from avoiding horrible scenarios like 1:1 or 1:2, I don't put too much stock in room dimension ratios. The measured modes just never come out where the calculations say they will. If you could input all the acoustical data about the construction materials and construction details, you could model the room more successfully, but in practice you can only do that if you're building from scratch with acoustically rated materials and regular shapes. In which case it probably makes sense to hire Rives and have them do a real design job.

My current room is a good example of that unpredictability. By all rights, it should have horrible bass, since it's small and almost square. And yet it doesn't, it has problems in the mids and highs but the bass is just fine.

I think there are several reasons for that. To begin with, the speakers are like sources, so I've eliminated the vertical mode. Then, the room is broken up laterally, with a 6' opening into a hall. So the room isn't as square as the dimensions suggest and the lateral modes are broken up. The speakers are also positioned laterally in an asymmetrical way, which helps some.

This leaves mostly the depth mode and speaker positioning can take care of the worst of that.

Also, the room is very flexible and leaky, made of 315 year old wood and plaster with horsehair on lathe in some very flimsy walls, as well as having the labyrinth of halls with a bass minotaur at the end. All of which makes a very leaky, absorbent, and at the same time pleasantly warm and woody resonant room.

Higher up, the room is just too damn small, which I expected, and the fireplace mucks up imaging on that wall, which I didn't, since for some reason I didn't have that problem with the fireplace in my old room. I find there are always some surprises or quirks, like the ones you mentioned with your speakers.

The problem with the single-panel Maggies is that you do have to use toe-in, usually, because of crossover lobing or HF beaming. So you can't take full advantage of dipole bass, if you toe them in 45 degrees, you're going to be exciting both lateral and depth modes. Here are some great response graphs that compare monopole, dipole, and cardioid woofers both aligned with the room and toed in, towards the bottom of the page:

http://www.musicanddesign.com/Dipole_modesA.html

The dipoles have a huge advantage parallel to the front wall but that this advantage mostly disappears by the time they're toed in 45 degrees.

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Follow Ups Full Thread

Topic - Maggie placement... what works for you? - Tom C. 06:02:02 09/11/12 (21)

I start out measuring the room. then calculate fractions of room and skip bad ones - Elizabeth 18:39:10 09/14/12 (4)

RE: I start out measuring the room. then calculate fractions of room and skip bad ones - pictureguy 16:08:55 09/16/12 (3)

RE: I start out measuring the room. then calculate fractions of room and skip bad ones - josh358 18:17:55 09/16/12 (2)

RE: I start out measuring the room. then calculate fractions of room and skip bad ones - pictureguy 23:15:47 09/16/12 (1)

RE: I start out measuring the room. then calculate fractions of room and skip bad ones - josh358 05:12:04 09/17/12 (0)

RE: Maggie placement... what works for you? - magiccarpetride 10:49:32 09/14/12 (0)

Depends. - grantv 07:13:57 09/14/12 (0)

RE: Maggie placement... what works for you? - josh358 14:04:36 09/13/12 (0)

Try them here, there and everywhere - AudioDwebe 08:38:57 09/13/12 (5)

RE: Try them here, there and everywhere - pictureguy 13:36:08 09/13/12 (2)

RE: Try them here, there and everywhere - Norman M 10:30:45 09/17/12 (1)

RE: Try them here, there and everywhere - pictureguy 11:50:50 09/17/12 (0)

RE: Try them here, there and everywhere - Norman M 09:33:55 09/13/12 (1)

Change is the only constant - AudioDwebe 16:18:28 09/13/12 (0)

diagonal - farfetched 18:00:38 09/11/12 (0)

I suggest you will not find uniformity - as room size plays a big part, IMO ... - andyr 14:51:16 09/11/12 (0)

RE: Maggie placement... what works for you? - tyu 10:12:01 09/11/12 (0)

Nearfield - scruffy_ 08:21:18 09/11/12 (3)

RE: Nearfield - pictureguy 00:32:52 09/12/12 (2)

RE: Nearfield - scruffy_ 03:41:14 09/12/12 (1)

RE: Nearfield - pictureguy 13:38:33 09/13/12 (0)

Follow Ups

RE: I start out measuring the room. then calculate fractions of room and skip bad ones - josh358 05:12:04 09/17/12 (0)

RE: I start out measuring the room. then calculate fractions of room and skip bad ones

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