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atomicAdam
05-10-2009, 08:29 PM
So the at moment I've got my Monitor Audio RS6 speakers in a small room. Roughly 8x11x7.5. Not ideal for the size of these speakers, I know, but hopefully that will change in the somewhat not too distant future.

So, suggestions? I was considering the Owens Corning 703 bass traps or Rockwool traps. None of the hardware stores around my area seem to carry Owens Corning 703.

Suggestions for treating a small, carpeted room?

Thanks

JoeE SP9
05-11-2009, 09:20 PM
You can't go wrong by damping the first reflection points.

luvtolisten
05-12-2009, 05:58 AM
Sometimes, the least expensive way out is speaker placement. I guess it depends on what type of sound you are trying to correct, are they a muffled? Overly bright? (I have heard of folks placing tissue between the tweeter and grill to help that). Can you describe what it is you don't like about the sound right now?

Auricauricle
05-12-2009, 08:03 AM
When you use the phrase, "dampen the first reflection points", what do you mean, JoeE? "Dampen" as in apply a trap? How big? Does the size correspond to the speaker's size, e.g.? Where are the first reflection points? Directly in front or behind the speakers? To the side? Enthrall us now, with your wisdom!

bfalls
05-12-2009, 08:47 AM
One method I've read for finding the first reflection point is to take a mirror and it along the wall. If you can see the speaker in the mirror, it's a reflection point. It's the first room boundary the sound will hit when leaving the speaker. The sound from a reflection point will bounce off the point and get to you ear after the primary sound causing the image to blur and be less defined/detailed. You can also have reflection point on the floor and ceiling as well, also off the back wall. Another sound artifact would be standing waves caused by low frequencies running along the wall and collecting in corners and seams where wall meets wall or ceiling.

E-Stat
05-12-2009, 10:07 AM
... take a mirror and it along the wall. If you can see the speaker in the mirror, it's a reflection point.
Exactly. There are some measurement based methods as well, but they do not work in my room. Here's (http://www.realtraps.com/art_room-setup.htm) one from the Real Traps folks.

As for me, I use fake ficus plants although my music system is quite different in that dispersion is relatively narrow and there are no tweeters!

Ficus solution (http://home.cablelynx.com/~rhw/audio/ficus.jpg)

rw

audio amateur
05-12-2009, 01:40 PM
I love your room EStat...

Auricauricle
05-12-2009, 02:56 PM
So, my cassia is out, huh?

JoeE SP9
05-13-2009, 06:34 PM
When you use the phrase, "dampen the first reflection points", what do you mean, JoeE? "Dampen" as in apply a trap? How big? Does the size correspond to the speaker's size, e.g.? Where are the first reflection points? Directly in front or behind the speakers? To the side? Enthrall us now, with your wisdom!
Please excuse my terminology.
Place a sound absorbing material on the side walls where the speakers first reflection point is.
The point is determined by having someone move a mirror along a side wall while you are in the sweet spot. There will be a position where you will be able to see the speaker closest to that wall in the mirror. That's the first reflection point. Place sound absorbing material (ideally) from floor to ceiling and 1 foot to each side (2Ft. wide total) of the reflection point. More width may be better but not always. Don't go overboard and apply too much. This is effective with all speakers. Box speakers respond especially well. IMO it makes them sound less boxy.
This also applies to the ceiling and floor. Floors usually have some covering on them already. If the floor is bare a nice throw rug can do wonders.

Hanging large beach towels in the first reflection points will be a more than adequate demo. How's that for a really cheap tweak!

kexodusc
05-14-2009, 06:50 AM
So the at moment I've got my Monitor Audio RS6 speakers in a small room. Roughly 8x11x7.5. Not ideal for the size of these speakers, I know, but hopefully that will change in the somewhat not too distant future.

So, suggestions? I was considering the Owens Corning 703 bass traps or Rockwool traps. None of the hardware stores around my area seem to carry Owens Corning 703.

Suggestions for treating a small, carpeted room?

Thanks
Sorry I'm late to this.

I couldn't find the rigid fiberglass or rockwool in our local hardwarde stores either other than a trace amount at one spot only availbe in 1" thickness. They could order some in for me but I would have had to make a huge order. So I started calling around to industrial A/C and heating joints, and eventually found a distributor who was happy to ship me a truck load at wholesale prices. Even their retail prices were far better than what the hardware store was going to sell it to me for. Took me about 20 minutes of web surfing and phoning to track some down.

If you build your own traps, nothing wrong with Owens Corning, but for whatever reason they are usually the most expensive brand. There isn't a preferred brand, they all make the stuff with absorption coefficients down to the 3rd decimal or so, close enough for our purposes. Most DIY'ers just go with what's available and cheapest (and OC is usually widely available).

Mineral wool is just as good, but IMO a bit harder to work with since it doesn't really keep a shape. Good for stuffing into frames or structures that will support it but otherwise you have to work around that. Not always cheaper either.

LJ, Rich, and I have all built traps here, and I think a few others as well so there's lots of help around if you need any.

Edit:

One last thought - I also have some expensive Auralex and Sonex acoustic foam panels I used at reflection points previously. They're ok and easy to work with and will offer some improvements, but IMO are not quite as effective (as measured in my room) and not nearly as cost-effective as the fiberglass/mineral wool panel solution. If anyone asked me, I'd recommend buying quality pre-built traps over acoustic foam for simple wall panels or corner traps. Foam has its place in some rooms though, particularly if high WAF is required, and have more application-specific products (i.e., dispersion/absorption panels) too that could be used as part of a total room treatment with thicker fiberglass panels/traps. Just my 2 cents.

E-Stat
05-14-2009, 08:55 AM
Suggestions for treating a small, carpeted room?
The simplest bass trap solution is Jon Risch's Quick and Dirty trap formula. Translation: stacks of rolled insulation placed in the room corners. Seriously. Works pretty decently. I later commissioned my sister-in-law to stitch some spandex "socks" for appearance sake. There are quite a few other DIY formulas available as well. My current "trap forest" uses the sealed pipe insulation recipe found here. (http://home.comcast.net/~thomasw-2/SubwooferSetupandEQpage9.html)

I'm a big believer in room treatments.

rw

E-Stat
05-14-2009, 08:59 AM
I love your room EStat...
Thanks! One of the secrets to long term marital bliss for audiophiles is having a "man cave". :)

rw

atomicAdam
05-14-2009, 10:45 AM
Thanks for the feed back folks,

My original post was particularly vague to see what would come up and I could respond better after that.

The room currently has 1in" thick egg shell foam in several spots around the room. Corners behind the speakers and above the shelves on the opposite wall of the speakers. I've spent the last month positioning and repositioning the foam to get it dailed, along with speaker placement.

Reflection from my tweeters or 'high frequencies' is basically taken care of at the moment. The problem I found now is that with the RS6 speakers, the bass ports up front have to typically be plugged to reduce a BOOMing effect when the music is turned up.

The booming I speak of is similar to the BOOM you get from hiphop-mobiles and their tin can rattling trucks. Lots off bass that all kind of sounds the same.

But I have notice that with the bass ports in the front of the speakers unplugged, I get, along with the BOOM more depth and detail to the lower end.

I've stood up and put my head around the room and at different places the BOOM is either louder or quieter. It is quieter when I am in my chair, which is good. But I would like to be able to play my music louder w/o increasing the BOOM or totally irritating my neighbors.

So I figure bass traps would be best. Make my own, only cost $100 bucks or so for 6 24"x48" traps and experiment with placement around the room to see what happens.

Unfortunately went to HomeDepot and they don't sell the OC 703 unless I buy 10 cases of 6 boards that are 4ftx8ft. So 60 4x8ft boards. I don't even think though would fit in my whole apartment.

I'll try calling around to come heating and air conditioning places around the bay area, but probably just got with the $77 for 6 24"x48" boards I found online.

Auricauricle
05-14-2009, 11:15 AM
I'll just stick with the ficus!

atomicAdam
05-14-2009, 11:32 AM
I'll just stick with the ficus!

Is this the ficus you speak of?

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O'Shag
05-15-2009, 01:10 PM
Hi Adam -

I have Monitor Audios also. My room is not very big and is approx 15ftx24ft. I currently live in an apartment building, and moved from the first to the second floor. I now have my system oriented against the short wall, where it was against the long wall before. This means the speakers project sound the length instead of the width of the room, and my listening position is no longer nearfield. Where my main listening chair was only about 8ft from the speakers before, I now sit about 13ft-14ft back.

While I really love my new apartment over the last one (much brighter with a better view of the girls walking by :yesnod: ) I was not prepared for the dramatic change in response characteristics listening to two-channel. Before, I was immersed in sound, and the new setup has the essence of the music existing in the front quarter of the room, and finding it difficult to break free of this 'zone', with the result of a serious disconnect with the music.

The importance of room acoustics has been driven home hard. I understand that the room acts as a comb filter at certain frequencies and that such effects as floor bounce create cancellations and unevenness in bass response. The thing is as I live in an apartment, I didn't want to go all nuts about treatments.

I've just cured the problem with what is one of the most astonishing products I've ever encountered. I'm a sceptic because the audio industry is infested with balogny. The product is called the Argent Room Lens. I got five of them (original not copies). You know a product is special when without careful setup, just kinda thrown in the general spot, and there is immediately a VAST difference in the sound. What the Argent Room Lens does is to act as a resonator and smooth out response characteristics. The thing I noticed immediately was the way the sound was freed from that first quarter of the room. Instantly, there was so much more clarity and focus - something I had become accustomed to in my previous setup. I can turn the volume up without any hint of 'distortion' in the sense of blurring of the sound, or boomy bass.

I can vouch for the extraordinary results in my smaller far-from-ideal room, but can't say what the results would be in a larger room - perhaps not so dramatic. So from one Adam to another, if you find these for sale (they must be the originals not gimmic copies that are just plastic tubes) do not hesitate to buy them. I guarantee you'll be floored at the results. I should also add, that because they are no longer made, if you don't snap them up same day, they will certainly be bought by someone else.

jrhymeammo
07-05-2009, 12:02 PM
Ficus solution (http://home.cablelynx.com/%7Erhw/audio/ficus.jpg)

rw

Hey E, Nice room. Not overly dampened and well placed.
Is that a diffusor panel behind your SL? If not, have you tried a set of diffusor?

JRA

jrhymeammo
07-05-2009, 12:06 PM
I've just cured the problem with what is one of the most astonishing products I've ever encountered. I'm a sceptic because the audio industry is infested with balogny. The product is called the Argent Room Lens. I got five of them (original not copies). You know a product is special when without careful setup, just kinda thrown in the general spot, and there is immediately a VAST difference in the sound. What the Argent Room Lens does is to act as a resonator and smooth out response characteristics. The thing I noticed immediately was the way the sound was freed from that first quarter of the room. Instantly, there was so much more clarity and focus - something I had become accustomed to in my previous setup. I can turn the volume up without any hint of 'distortion' in the sense of blurring of the sound, or boomy bass.



Hey Shag,
I have been thinking too long to acquire a set. I should just go for a DIY approach, since they are rarely seen on Agon at reasonable price. What are the tubes made of? For now, I'll just leave a couple of tall lamps next to my speakers.

JRA

E-Stat
07-06-2009, 04:04 PM
Hey E, Nice room. Not overly dampened and well placed.
Is that a diffusor panel behind your SL? If not, have you tried a set of diffusor?
Thanks. You're probably referring to the bass traps. They allowed me to get very linear results for the bottom three octaves (+- 1.5 db from 30 hz to 200 hz). Closer pics are found in my profile over at AA here. (http://gallery.audioasylum.com/cgi/view.mpl?UserImages=2150) I have subsequently removed the wall panels as they ended up overdamping the image.

rw

E-Stat
07-06-2009, 04:10 PM
You know a product is special when without careful setup, just kinda thrown in the general spot, and there is immediately a VAST difference in the sound. What the Argent Room Lens does is to act as a resonator and smooth out response characteristics.
I tried them, but they didn't do much for dipoles. I think they are more effective for direct radiators.

rw

jrhymeammo
07-07-2009, 05:38 PM
Thanks. You're probably referring to the bass traps. They allowed me to get very linear results for the bottom three octaves (+- 1.5 db from 30 hz to 200 hz). Closer pics are found in my profile over at AA here. (http://gallery.audioasylum.com/cgi/view.mpl?UserImages=2150) I have subsequently removed the wall panels as they ended up overdamping the image.

rw
Hey E,
I was not referring to your bass traps, but the wall panels.
Have you considered a pair of diffusors instead? Q'Fusor and Metrofusor by Auralex seems very reasonable.
If I was to start this hobby all over again, I would spend $1000 on room acoustics over cables/tubes in a heartbeat.

It's too bad people do not even consider acoustics while they spend thousands on a gear for incremental benefits.

JRA

E-Stat
07-07-2009, 06:16 PM
Hey E,
I was not referring to your bass traps, but the wall panels.
Ok


Have you considered a pair of diffusors instead?
No, I haven't but I get a very good image as the traps do provide some diffusion as well. There are two more trap columns at the mid points of the room as well.


If I was to start this hobby all over again, I would spend $1000 on room acoustics over cables/tubes in a heartbeat.
My treatments are all DIY so they cost me a good bit less. I guess I have around $600 in mine.

rw

jrhymeammo
07-07-2009, 06:50 PM
Ok

Cool.



No, I haven't but I get a very good image as the traps do provide some diffusion as well. There are two more trap columns at the mid points of the room as well.
fair 'nuff



My treatments are all DIY so they cost me a good bit less. I guess I have around $600 in mine.
rw
$600 in DIY? What's it made out of? Gourds Phallocrypts?

Jay'amos

E-Stat
07-08-2009, 09:07 AM
$600 in DIY? What's it made out of? Gourds Phallocrypts?
Well, it all adds up. Here is the approximate breakdown:

(8) Knaupf 18" diameter pipe insulation - $160
(4) Knaupf 13" diameter pipe insulation - $60
(24) wooden cake boards (as caps) - $100
~ 25 yards spandex cloth - $200
Glue caulk / gun - $30
Wood framing (for panels) $20
Insulation - $20
Hangars / wire / plastic backing - $10

An equivalent set of ASC traps alone (not counting three damping panels) would run something like $3200!

rw