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First wall reflection.


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For treating first wall reflections high density fiberglass or rockwool absorber panels do a fine enough job. 

Quilts aren't usually thick enough to do the job correctly since they only absorb high frequencies, but they're still a lot better than nothing.

In all honesty room choice and its treatment are almost as important as choosing speakers. It can be modeled to a degree ( http://www.acousticmodelling.com for instance offers some basic modeling tools), but most of it needs to be measured in order to achieve optimal results. A decent USB omni-directional calibrated microphone can be had for less than $100 and some great software like Room EQ Wizard is actually freeware. Having these basic tools empowers you to know exactly what effect acoustic treatment products have.

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Thanks for sharing.  I don't have any bass issues as I have a very open loft.  Johnny Rutan came to set up and calibrate the room.  The quilts make a nice difference.  I don't have a dedicated room, but my wife puts up with a lot.  That said, she's not keen on wall treatments, even the ones I have that you can have pictures on.  Just something I deal with, lol.  It's all good though since the room sounds decent without treatments. I don't even have a slap echo problem, so I don't 'worry about treating the ceiling.  I believe there is a 99% chance that would be vetoed quickly, lol.  :). 

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Yes, just saw that.  I'd make my own wood stand to match them.  I need to see which of my dealers sells them.  I like the idea of a stand to put them on the back wall and then I can move them when needed.  Not sure if I'd need three or if I can just use two and leave the bottom open.  I'm sure the dealers will know.

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  • 2 months later...
  • 3 months later...

ct, ceilings can also be an issue.  In his infinite wisdom, Johnny Rutan also gave me a tip on ceiling reflections.

Tape or glue an old cd (shiny side facing out) to a yardstick.  With someone on a ladder, holding the stick against the ceiling,  sit at your listening position and point a laser at the cd.  By moving it around, find the spot where the laser reflects off of the disc right onto your tweeter.  That is the spot on the ceiling you want to put a diffuser.

I used to use bathroom floor mats.  I've since upgraded  ☺️ to egg crate-like mattress pads.

Disclaimer:  huge amounts of WAF required 

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  • 2 months later...

You want something with some thickness, at least 4 inches.  I recommend the 24" x 48"  x 4" panels from Atsacoustics.  They can supply their own mounting hardware, but since they are wood backed, I just used picture hanging hardware from Home Depot.    The panels cost $72.95, which I think has the decimal point in a more reasonable place

 

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Interesting. I BET I can tempt her with teh coffee bag covers ones. She's a HUGE coffee fan and that would be cool.  I have heard good things about their gear.  I've heard it in stores and the rooms sounded good, but I didn't know how they sounded before, lol.  

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i think it depends on how far away the back wall is - whether you use diffusion or absorption. i built some 2ft x 4ft x 2in (or 3?) deep panels out of rockwool insulation. another popular is OC703 fiberglass. i wrapped them in burlap. and let me tell you, you put your ear up next to those and it's dead on higher freq.  there's ratings for absorption  depending on freq.  i always thought diffusion was for sides of the seating area?  but i think instead of a quilt or blanket, a good tightly bound oriental rug is what you want, something dense.  put a blanket over your head and see what you can hear through it. you might have to take whatever you use and fold it to double the thickness.

there's also the live-end dead-end theory. the wall where the speakers are is full of sound absorbing material and first reflections on ceiling and side walls are absorbing, then nothing behind you. it all depends on the room and how far away you sit from the side and back walls.

plus there's a theory about putting speakers on either side of the corners of the room so your sitting facing the corner of the room when you are listening.  but this can eat up a lot of realestate and make a big room seem tiny 🙂

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I may just do the coffee bag absorption ones instead of the quilt. The wife loves those (she's a coffee freak).  I was told diffusion behind me. I"m in a loft with a 50" high half wall behind the speakers. It's open to the stair case up there as well as the hallway to teh bedrooms.  The first reflection of the right speaker is on the wall on the staircase.  I'm about 10' from the speakers and I have another 12' behind my chair to the wall.  It's a tough room, but sounds decent considering.

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ah. i see. i saw your photo in the room photos forum. so you have a fair amount of distance behind you. i could see either absorbing back there a bit or the diffusion. i think the diffusion would give a nice effect of space around you without being too distracting or muddying up what's in front of you. it delays the reflection in a way as well as obscuring the sound.

i think i see that the right speaker is open there now that i have taken a better look. it also looks like an afghan/blanket is over the railing?

so you have a rectangle room which looks about 10-12ft wide and 22ft long.  on the right is not a wall, but a stair case railing - the entire 22ft?  and the wall behind you is a full height wall?

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Yes, Rutan told me to go with diffusion behind me.  I wish those coffee bag absorbers were diffusers, lol.  Wife loved them.  

The room is about 17' wide I believe.  I'd have to measure.  It's about 22' long. The stair case is only 2 spindle sections long and the landing leads to a hallway for bedrooms.  Rutan likes to set up in the corners of the room.  That quilt was the one I purchased for the wall on the staircase wall where the first reflection would be.  I can easily buy the coffee bag absorbers for that wall and use the quilt in some other capacity.  I was going to just build a removable wall  for the first 4' of the staircase spindles that are right next to teh speaker.  

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oh. i was quite a bit off on the width. i thought maybe the cabinet might be 4ft and was going off about 3 of those.  interesting setup.  yeah you  know seems to me that an old stereophile review of the 2ce's said the speakers were about 1ft away from side walls and toed in towards the listening position.   i suppose i have a spot where i could do that, might have to give it a try some time.

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