[woodsyi]

I can't do it anymore.  I have had enough of plugging and unplugging of connections and moving gear on and off the rack just to move the rack a few inches.  I would like to add another sub but I can't find room for a second.  So I moved it to the center between the speakers.  I would like to get a comprehensive room treatment solution rather than adding a trap here and there on ad hoc basis.  Back wall is hollow behind the panel but the right and back walls have fiberglass insulation between the panelling and cinderblock walls.  http://www.audiocircle.com/index.php?action=gallery;area=browse;album=488
Any suggestions?

[Ethan Winer]

Woodsyi,

> I would like to get a comprehensive room treatment solution rather than adding a trap here and there on ad hoc basis. <

Thanks for sending a private message inviting me to suggest how I'd treat your room with my company's products. I mention this so others here don't think I'm spamming the group!

Your gallery photos don't show the room dimensions, or even which way the speakers are oriented (long way? short way?), so I'll have to guess at some of this.

Most important is to get enough bass trapping in the room. This means at least four MiniTraps, and you can go up from there. More MiniTraps, and/or MondoTraps in place of some or all of the MiniTraps.

The drop ceiling is a great opportunity to get even more bass trapping by laying fluffy fiberglass above the tiles. This is inexpensive, and it's hidden so you don't have to spend time making it look good. If you have room for foot-thick batts that's the best choice. Otherwise use whatever thickness will fit, and cover as much of the space as possible especially around the perimeter. You still need bass traps inside the room in the corners, but having a lot of fiberglass above the ceiling really helps too.

The next step is to address first reflections off the side walls and ceiling. Again, I can't see enough of the room in context to advise you further. But I'm sure the article How to Set Up a Room on the RealTraps site will be useful. Here's a direct link:

www.realtraps.com/art_room-setup.htm

Please let me know if I can be of further help.

Thanks.

--Ethan

[woodsyi]

The room size is 16' from back to front.  The width is 22'  at the back but 18' at the speakers.  but the speakers at set at 4' from the sidewalls and 6' from the back wall.   My listening position is against the back wall.

[Ethan Winer]

Woodsyi,

> The width is 22' <

That implies you have the speakers facing down the shorter dimension. If possible, you'll get a better low end response if you rotate the setup 90 degrees so the speakers fire the long way down the room.

> My listening position is against the back wall. <

That too is not ideal. The inevitable peaks and nulls are always worse as you get closer to the wall behind you. Again, the article I linked above explains the best way to orient yourself and your speakers. The better you can make things to begin with, the more you'll benefit from adding bass traps.

--Ethan

[woodsyi]

Ethan,

I read your article and it would be a PITA to move everything, but it can be done.   Before I do this, however, what do you think of this article?

http://www.immediasound.com/Speakersetup.html

[ctviggen]

Also, you might think about treating the front.  I bought microtraps and stands from RealTraps, and I put these in front of my RPTV/matching stand, and the difference is quite astounding.  I'm thinking of buying one more microtrap and stand to ensure that I completely cover the entire front of the room.

[warnerwh]

The results will easily speak for themselves. You have a very nice system. Room acoustics are major, as much as speakers or pretty close.  If you can get some good treatment like what Ethan sells and do some of it yourself you'll be amazed at the quality of sound improvement for the money expended.  Also getting away from that rear wall even a few feet will help alot.  I suspect I've spent less than a grand on my dedicated room's acoustics and it is worth every penny. The upgrade is far superior to electronics and will make those RM 40 sound much better than you've heard them unless you've heard them in a quality acoustical environment.  I believe George (Zybar) did alot of room treatment and just kept going.  You may want to contact him as I believe he is using RM 40's also. Once you start and hear the differences it's hard to stop til you've done the whole thing.  Then you'll have little respect for reviews where the room was not a very good acoustical environment. The difference is truly major.

[John Casler]

I can't do it anymore.  I have had enough of plugging and unplugging of connections and moving gear on and off the rack just to move the rack a few inches.  I would like to add another sub but I can't find room for a second.  So I moved it to the center between the speakers.  I would like to get a comprehensive room treatment solution rather than adding a trap here and there on ad hoc basis.  Back wall is hollow behind the panel but the right and back walls have fiberglass insulation between the panelling a ...

Hi Woodsyi,

I see several quick areas to offer dramatic improvement, if you are going to be maintaining your current speaker and listening positions:

1) Either remove or heavily soundproof the coffee table.  It is of the height to give you low incidence direct reflection that is definatly blurring you mids and highs

2) Either remove or again cover the cabinet in front of the right speaker.  It is probably giving you some very nasty reflection also.

3) Since you are so close to the rear wall, you need some heavy 3-4 inch foam over those windows, and VERY HEAVY sound absorbing drapes instead of those sheers you have up now.

Then you have to decide about bass.

How is your bass now?  If it is satisfactory, then don't do anything, but my best bet is that it could be a little boomy.  If so, you may need traps to solve the problem.  You may also need to move the couch further off the wall.

Then you have a few more options:

1) Place acoustic treatment in most of the room corners and tri-corners.
2) Place treatment at all areas of first reflection
3) Place treatment behind the speakers on the front wall
4) Place treatment on the front wall between the speakers

or use a "speaker hood and overcoat" like I have been using either temporarily or full time, on the speakers to keep dispersion to almost nothing (like a LEDE).

[Ethan Winer]

Woodsyi,

> it would be a PITA to move everything <

Of course it's a PITA! But it really is worth the effort. Without too much trouble you could try it temporarily before you move everything just to convince yourself it will be worth the effort.

> what do you think of this article? <

Seeing the listening position up against the rear wall tells me all I need to know.

There's an ETF graph showing the low frequency response in the same room both ways (lengthwise and widthwise) in our recent review in Sound on Sound magazine. Follow the link from the main page of my company's web site.

--Ethan

[woodsyi]

Well,

It's not just PITA, but it's also low on WAF.  Thanks to the snow, there was no golf and I spent the Saturday morning rearranging things to rotate the orientation.  I left enough room in the corners for traps and coffee table has been banished to the laundry room.  As I suspected I got the LOOK from my wife.  I told her it's temporary and I will figure something out to make it practical.  She did not like that I only had one recliner at the listening position with everything else banished to the side.  

With room configuration having 16' width, 22' depth and 7' height, would the following be enough?

Fluffy fiberglass (insulation?) above the drop ceiling tiles betweeen the speakers and the listening position.

1 mondo trap each at the lower main corners behind the speakers.

1 2X2 mini trap each at the top corners above the mondo traps.

1 2x4 mini trap each at first reflection point on side walls.

1 2x4 mini trap place side ways on the rear wall between the speakers.

Do I need need more?  Can I substitute mondo with mini?  Can I omit the top corners?   In other words, what is the least I can spend to get the most VALUE in acoustic treatment to get a good sounding room.  I want to spend enough to get a "good" sounding room but not an exorbitant amount to get a "great" one.  Bear in mind that I listen mostly to vinyl recordings of orchestal, operatic, jazz, folk and bluegrass music.

[Ethan Winer]

Woodsyi,

> 16' width, 22' depth and 7' height, would the following be enough? <

Yes, that's certainly enough to make a noticeable dent, anyway. Acoustic treatment, and especially bass traps, is all about coverage. So the more you add, the flatter and tighter the low end will be.

> Fluffy fiberglass (insulation?) above the drop ceiling tiles betweeen the speakers and the listening position. <

That will help further with bass trapping if you pack the entire cavity above the ceiling tiles with foot thick batts. But for control of first reflections either 1) your tiles are hopefully very absorbent, or 2) you can add absorbers underneath the ceiling tiles inside the room. If you have standard office style tiles, those are not particularly absorbent at high frequencies. In that case you'll do well to replace selected tiles at the reflection points with better tiles made of rigid fiberglass having only a minimal (plastic) surface covering.

> 1 2x4 mini trap each at first reflection point on side walls. <

That's fine, but you want the HF type there, not standard MiniTraps.

> Can I substitute mondo with mini? Can I omit the top corners? In other words, what is the least I can spend to get the most VALUE <

Again, the more trapping you have the better. If you can manage all the traps you listed, that will be better than fewer. Especially since you're near the "minimum useful" end of the range already.

--Ethan

[ctviggen]

Ethan,

How do you figure out where to put traps on the ceiling?  I have a home theater and would like to reduce ceiling reflections from my center channel and my right and left front channels.  Do you sit in the sweet spot and have someone put a mirror on the ceiling, then mark the locations where you just begin to see the speaker (the part with the drivers)?

[John Casler]

Ethan,

How do you figure out where to put traps on the ceiling?  I have a home theater and would like to reduce ceiling reflections from my center channel and my right and left front channels.  Do you sit in the sweet spot and have someone put a mirror on the ceiling, then mark the locations where you just begin to see the speaker (the part with the drivers)?

I'm no physics expert, but I would think that all you would have to do is measure the distance between the speaker and the listening area and divide by 2.

I beleive it should be a simple equilateral triangle.

I could be wrong

[ctviggen]

That would make sense -- reflections before or after that point wouldn't hit your ears.

[woodsyi]

I did it.  I took all the advices, churned them through my CPU, formulated a plan, CHECKED WITH MY WIFE, spent time and money and ended up with this for now.  http://www.audiocircle.com/circles/modules.php?set_albumName=woodsyi-s-room&op=modload&name=gallery&file=index&include=view_album.php

You can see pictures from  before and after room treatment.  I also stuffed 4 main corners above the ceiling tile with 1' thick fiberglass insulation bat.  The sonic improvement is very satisfying.  I even took more mortite off all three passive radiators to liven them up.  I have punchier and tighter bass.  At the same time treble improved as well from 1st reflection point treatment.  I love the sound but it's not sonic nirvana, yet.  The tricky part is from 180 to 300 Hz region.  It's good with female voice but a tad boomy with male voice.  I have to try different x-over frequncies and I may need some diffusion stuff as well, but I am going to wait until I upgrade the midbass woofer and install Bybees filters in the drivers before going further.  

After I put my girl to sleep, I make it a point to come back and listen with lights off to see the tubes glow.  Puts me in the right frame of mind before going to asleep!

[woodsyi]

Ethan,



For mid-high frequency bending off the inner corner of the speakers, should I split the micro traps so that each trap will be closer behind the speakers?



I did the mirror trick to bounce off the near (left channel) speaker.  There is a point further back on the wall that shows the far (right channel)speaker.  Is this point as critical as the one already covered?  In other words, are the two 1st reflection points from 2 speakers on the same wall equal in affecting sound quality?

[Ethan Winer]

Woodsyi,

> are the two 1st reflection points from 2 speakers on the same wall equal in affecting sound quality? <

The short answer is any place you can see either speaker in the mirror is a candidate for absorption. However, the width of the room is a factor too. First reflections are sometimes called "early reflections", and there's a subtle but important distinction.

A first reflection point is the first place sound reflects. An early reflection is one that arrives within about 20 milliseconds of the direct sound. So that place farther back on the left where you can see the right speaker is indeed a first reflection point. But that reflection won't be "early" unless the total path from speaker to wall to ear is about 20 feet or less.

If it were my room I would treat all of the places where either speaker can be seen in a mirror. But assuming your room is as large is it appears, and the total distance is 20 feet or more, it's less of a problem than the more-forward side wall reflection point.

--Ethan

[woodsyi]

That makes sense.    Thanks Ethan.  There are so many things in this hobby that is just "voodoo," but this distinction between 1st reflection and early reflection makes sense.  The second 1st reflection would indeed be longer than 20 ft.  I may get back to you for more stuff later, but for now, I am just going to sit back and enjoy for a while.

[Ethan Winer]

Woodsyi,

> There are so many things in this hobby that is just "voodoo" <

I'm trying my very best to thwart those with a vested interested in making it seem like that!

--Ethan