[Nils]

This might be a stupid question--Is there an acoustical difference between the two setups below?  Is the staggered setup better?  I noticed that you could stagger them a bit and have the large well still line up...




My room's almost done... will post pics soon!

-- Nils

[Jason Jones]

Nils,

Depending on the location and the rest of the room set-up it could be better, worse or no different. How's that for an answer!

Used in a vertical stack like yours, this relative positioning can help some with the 300-500 hz region. These frequencies don't really "see" all of the details of the panel - 500 hz does to some extent, but at 300 not really at all. Down below 500 hz we really need to start to think about each diffuser as being a "well" in a larger diffuser.

I'm going to be out and about all day, but feel free to ask any follow-up questions. It has been kinda fun to watch all of your experimenting here on the circle. I love curiosity!

Jason

[Nils]

So here's a little diagram I threw together.. not the most detailed, but I think it'll do.  Everything is more or less to scale

triangles in corners = 2 stacks of 2 GIK tri-traps
green = GIK D1 panels, 4' high stack
turquoise = RealTraps HT minitraps (2' x 4')
white panel = RealTraps RFZ panel (32" x 42")
black = Maggies!
circle = happy place



Note there's a hallway opening right behind the happy place, which is why there's no treatment there

[mfsoa]

Nils -
To add another wrinkle - Have you tried the D1s with the ribs running horizontally? (Or alternating vert/horiz?)

I just got a pr of D1s and have been playing around with them behind my Von Schweickerts which have a rear-facing ambience tweeter.

Everyone that's heard has preferred the D1 in the horizontal position - With them vertical, the diffused sound is directed back horizontally at the height of the listening positions, resulting in a relative increase in the amount of the rear wave that gets to you. This tips up frequency response and I also thought it provided too much "non-direct-speaker-radiated" sound. The depth was good but just too much reflected signal left combining with the main waveform.

With the panel channels horizontal (in both horiz and vert orientations, I have a single D1 sitting directly upon a 244 panel that's on it's side, the 244 angled slightly against the wall) the sound is diffused vertically. This results in far less of the diffused energy getting back to the listener. Depth was not as good but image focus and overall sense of clarity (more imp to me than deep, diffuse type of sound) was greatly enhanced.

Now another variable - When arranged vertically, it was clearly audible to hear the difference in having the panels rotated 180° - (Refer to pics above): With the "2 smaller rib side" on the inside of the speakers there was much more high freq content than with them on the outer position.

Good luck and keep us posted!

-Mike

[bpape]

That's what I love about Jason's design.  It offers a ton of flexibility to use however best fits your situation and preference.

Mike. 

Did you try them at 45 degrees?  That should give you the spreading in the vertical dimension but still give you some added depth in your particular setup.

Bryan

[Nils]

Nils -
To add another wrinkle - Have you tried the D1s with the ribs running horizontally? (Or alternating vert/horiz?)

...
...

Good luck and keep us posted!

-Mike

I experimented with horizontal placement (i.e. ribs running horizontally) behind my Magnepans, but I didn't like the effect.  Interestingly enough, said placement resulted in a brighter, less diffuse sound for me!  Perhaps the different result is caused by a few factors:

- absorption on the rear wall?
- line source dipoles

FYI, I lined my D1 panels with RAAMmat constrained layer damping and also stuffed the longer ribs with pieces of my old Sonex Junior panels.  They're also painted to match my walls.  (pics to come soon!)  Yay hot-rodding

[Nils]

Forgot a few things in my diagram.  I have two GIK Monster Bass Traps in the lower-right corner (this 12' x 17' setup is part of a larger 17' x 22' room) and 4 ASC StudioTraps treating the sidewall first reflection points.  I also have 5 leftover ASC SoundPanels, which I may use to treat the ceiling (but it might not make much of a difference, what with line sources that fire horizontally).

-- Nils

[Jason Jones]

OK, I am back. I spent the entire weekend at CoffeeFest. That's a big deal for us Seattle-ites!

With the set-up you (Nils) showed above, I can't see the offset you described making much of a difference. It shouldn't hurt anything, but probably not help much either. At close ranges 6-10 feet, slight positioning changes can be pretty significant. Beyond that, though, positioning is not quite so sensitive. I think you will get a lot more out of treating the ceiling than super-hyper-over-optimizing the diffuser placement.   

How long have you had those Maggies? I am thinking about getting a pair (sorry Glenn).

Jason

[Nils]

OK, I am back. I spent the entire weekend at CoffeeFest. That's a big deal for us Seattle-ites!

...I thing you will get a lot more out of treating the ceiling than super-hyper-over-optimizing the diffuser placement.   

How long have you had those Maggies? I am thinking about getting a pair (sorry Glenn).

Jason

Mmm, coffee.  I'm just sipping on a cup of freshly ground and brewed Rocket Blend.  We get good coffee where I work...

Thanks for the suggestions, Jason!  As far as the ceiling is concerned, I am about to treat it with 5 ASC SoundPanels.  They're light and aesthetically pleasing and mount very easily.  I'll give you an update when the ceiling is treated.

I've had maggies for 8 years now.  I first got MMGs when I was in college and loved the way they sounded (even in the constraints of a dorm room!)  Since then, I've upgraded some components and moved them into larger spaces... but the 3.6/Rs are only a few months old.  They're amazing, especially in a properly treated room.

The current hardware:
http://forum.audiogon.com/cgi-bin/fr.pl?vevol&1188229613&read&keyw&zzmagnepan