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poppachubby
10-18-2009, 02:56 PM
Hey All! In not so interesting news, I have decided to stay with the equipment I currently have for a while. I realize that i need to do some serious listening and learning before i can go any further. So I'll relax from the grind of shuffling components and just enjoy what I have. My plans are to start auditioning/listening at the local shops with some sort of regular frequency, perhaps once a week.

http://www.acoustics.salford.ac.uk/feschools/waves/pics/room.jpg

Aside from that, I am going to focus on room treatment and acoustical matters. It's really something that I know little about. I think that alot of audio types know little about this fascinating subject. There are only a couple of members here at AR that i have ever read references from.

http://www.asc-home-theater.com/ht-wilson-tt.jpg

I wonder how many "super" systems have been laid to waste by a poorly treated room. Don't get me wrong, my impressions of proper are far from correct. It just seems crazy that thousands of dollars will get spent, but the equipment will never reach its potential.

I want to study this subject so that i may use this knowledge in tandem with a good system. It's a vast and subjective topic swarmed by opinion.

http://www.decware.com/cs.jpg

I'm wondering who among you has planned their room "scientifically". I would love if you could share your room specs and what you've had to do to overcome bad traits. I've started my reading at E-Coustics...hope to hear from you!

http://www.ecoustics.com/Home/Accessories/Acoustic_Room_Treatments/Acoustic_Room_Treatment_Articles/

poppachubby
10-18-2009, 05:45 PM
....bump

Sir Terrence the Terrible
10-18-2009, 06:55 PM
Poppa,
I don't know about recently, but when this forum was just a pup, the mention of room acoustics was done daily. I have my minor degree in acoustical science, and good ole Dr. Green and several others had long discussions on the issue of room acoustics and sub placement. I really wish Audioreview had archived those discussions - there was a lot of very good information in them.

My new dedicated screening/mixing room was built from the ground up with sound isolation and acoustics in mind. Can't wait until it is finished, and i can set up my equipment in there. It sounds really good with nothing in it right now!

poppachubby
10-19-2009, 02:38 AM
Poppa,
I don't know about recently, but when this forum was just a pup, the mention of room acoustics was done daily. I have my minor degree in acoustical science, and good ole Dr. Green and several others had long discussions on the issue of room acoustics and sub placement. I really wish Audioreview had archived those discussions - there was a lot of very good information in them.

My new dedicated screening/mixing room was built from the ground up with sound isolation and acoustics in mind. Can't wait until it is finished, and i can set up my equipment in there. It sounds really good with nothing in it right now!

Well, with a degree in acoustical science, it would seem I need no one else to reply. I'm sure many topics are repeats for you old school AR types.

Would love to see some pics of your room once completed. Terrence, check out the room lens thread in the DIY section. In E-Stats post, what I figure is his old listening room is pictured. My room is very much the same. Drop ceiling, carpeted and drywalled. Mine is more square shaped. The real dynamic in mine is I'm using 25% of the room as my listening space. Picture a diamond, sources at the top corner, speakers at the side corners and seating at the bottom corner.

Firstly, with the room construction, would you assume I would need more diffusing than absorbing? Secondly, the room within a room, should I be addressing only what I hear from my seat, or should I consider how the sound moves through the entire space?

You can speak in generalities, I just need a push in the right direction. I'm finding the amount of info overwhelming at the moment. Thanks Terrence.

jrhymeammo
10-19-2009, 05:56 PM
There are tons of good information on the web. This site doesn't offer much info or response on room treatment. I think the link you've provided is a great start and should give you ideas on what you want want to implement.
I certainly don't understand all, and I'm pretty sure the setup I have isn't the best of what my room could offer.
Every room will react differently from others, so try to learn from trials and errors to find the best option for your room.

Have Fun,
JRA

poppachubby
10-20-2009, 01:37 AM
There are tons of good information on the web. This site doesn't offer much info or response on room treatment. I think the link you've provided is a great start and should give you ideas on what you want want to implement.
I certainly don't understand all, and I'm pretty sure the setup I have isn't the best of what my room could offer.
Every room will react differently from others, so try to learn from trials and errors to find the best option for your room.

Have Fun,
JRA


Ya thanks jr, you're right, zero response. I think most people don't want to get involved with anything that requires them to haul their gear around the room 50 different times.

Hopefully I can pick Terrence's brain along the way. I am certainly considering the room lens as I am quite certain I need some diffusion. My room is far from optimal as well. We'll see...

jrhymeammo
10-20-2009, 06:10 AM
Hey Pop,

If you can draw out a basic layout with dimensions, we might be able to help you out a bit. Speakers and major furniture positions will be helpful.

Yes, it is PITA to move your gear 180 degrees to find out everything sounds worst. I'm a bachelar so I can do whatever I please to the room. Not many wives will be please to see something like this hanging from a ceiling. They are indeed hideous, but they do control the hideous node.

6182
Have Fun,
JRA

E-Stat
10-20-2009, 03:30 PM
Aside from that, I am going to focus on room treatment and acoustical matters. It's really something that I know little about. I think that alot of audio types know little about this fascinating subject. There are only a couple of members here at AR that i have ever read references from.
While the treatments I used in my 20s weren't all that sophisticated (wall tapestries and DIY damping panels), my audio mentors always stressed the need for attending to the room. They clearly constitute a component in themselves. While not everyone can spring for a full treatment with bass traps and ceiling wings, there are many things that can be considered for virtually any living space. Carpeting, drapes and tapestries all serve to diffuse. Bookshelves are great diffusors. I use a forest of bass traps in my main listening room to provide very flat bass response (+/- 2 db from 25 hz -200 hz) and placed fake ficus plants at the speaker first reflection points. The room itself is irregularly shaped with dormers and bevels at the ceiling.

http://home.cablelynx.com/~rhw/audio/system0901.jpg
http://home.cablelynx.com/~rhw/audio/reartraps.jpg
http://home.cablelynx.com/~rhw/audio/room0109.jpg

I have treated my garage to an extent. I use three DIY damping panels and five Walmart mats (with an offset nubby pattern) that serve to minimize slap echo in the 26' x 26' space.

http://home.cablelynx.com/~rhw/audio/far.jpg

Currently, there are two more panels like the one centered oriented in landscape fashion on both side walls above the other panels.

rw

poppachubby
10-20-2009, 04:43 PM
I would imagine the garage enjoys the greatest benefit from your efforts E. Thanks for the response. What are your DIY traps made from? As I mentioned my baement is not unlike your first 2 pics. I would love yours and Terrence's input.

What do you need, a floorplan? I can promise you, there will be things you won't like but I am somewhat at the mercy of extended circumstances. Not my wife, just that the room has a shared function. Perhaps with your advice, I can approach it with a new point of view and still make it work.

Hope to hear from you, Chubbs

E-Stat
10-21-2009, 08:09 AM
I would imagine the garage enjoys the greatest benefit from your efforts E.
Well, at least the less-than-ideal space is no longer intolerably bright. There are still two bass modes with slightly elevated response (~3db) at 160 hz and 320 hz.


What are your DIY traps made from? Here (http://www.teresaudio.com/haven/traps/traps.html) is the recipe for the bass traps I use upstairs.


What do you need, a floorplan? I can promise you, there will be things you won't like but I am somewhat at the mercy of extended circumstances. Not my wife, just that the room has a shared function. Perhaps with your advice, I can approach it with a new point of view and still make it work.
Before you can attempt a solution, you must first identify the exact problems you wish to address! Upstairs, I wanted neutral bass and controlled radiation from the rear wave from my largish dipoles to provide optimum imaging.

rw

poppachubby
10-21-2009, 09:25 AM
OK E, to start, what do you feel the ideal distance should be between speakers to seperate a 2-channel set up?

jrhymeammo
10-21-2009, 11:47 AM
OK E, to start, what do you feel the ideal distance should be between speakers to seperate a 2-channel set up?

I think that's a huge question to answer in a forum. We will need more keyboards to answer that question.
You may want to read up on Cardas' Golden Ratio on the web.

Here is the sample, but there are many sites that discuss further on this topic.
http://www.cardas.com/content.php?area=insights&content_id=29&pagestring=Room+Setup+4

E-Stat
10-21-2009, 12:10 PM
OK E, to start, what do you feel the ideal distance should be between speakers to seperate a 2-channel set up?
Width-wise, I'd start with the simple to calculate "Rule of Thirds". Measure room width and divide by thirds. Place some tape at each third and center the speakers there. The Cardas recommendation also includes distance to back wall recommendations. The trick is that there is no one answer. Unfortunately, you must experiment. One needs to balance distance to side walls and optimizing overall image width. I am not a fan of speakers that require corner replacement because of the wall proximity effects on the image.

rw

poppachubby
10-21-2009, 01:54 PM
Width-wise, I'd start with the simple to calculate "Rule of Thirds". Measure room width and divide by thirds. Place some tape at each third and center the speakers there. The Cardas recommendation also includes distance to back wall recommendations. The trick is that there is no one answer. Unfortunately, you must experiment. One needs to balance distance to side walls and optimizing overall image width. I am not a fan of speakers that require corner replacement because of the wall proximity effects on the image.

rw

Perfect, thanks E. I have some re-congfiguring to do tonight. I'll catch up with you once I'm set up and ready to make another move.

poppachubby
10-21-2009, 06:11 PM
OK Mr. Stat, I have made some significant improvements. I am done for today but here's some pics.

First, a wide shot of the entire "listening" space, the room itself goes beyond the photos range.

http://gallery.audioreview.com/uploads/audio/284153/DSC02507.JPG

Next up, a close up of my digital world. I have my Pioneer PL 516 inputed to my soundcard which then goes to my dac. Been converting lately, fun for listening to...

http://gallery.audioreview.com/uploads/audio/284153/DSC02508.JPG

Finally the money shot. A view from behind my seat. I used the rule of thirds for width. I also used Cardas' formula for distance from the rear. I had to move a bit within this however, with young kids it's a speaker death wish. I would like to try and whip up some room lens next....any thoughts??

http://gallery.audioreview.com/uploads/audio/284153/DSC02509.JPG

E-Stat
10-21-2009, 07:13 PM
Finally the money shot. A view from behind my seat. I used the rule of thirds for width. I also used Cardas' formula for distance from the rear. I had to move a bit within this however, with young kids it's a speaker death wish. I would like to try and whip up some room lens next....any thoughts??
Looks good. The media racks on the left wall provide diffusion and the wall hanging behind the speaker provide absorption. You might try slightly less speaker toe-in though. Too much can narrow the stage width.

Here's (http://www.geocities.com/jonrisch/a3.htm) a DIY formula for building your own room lenses. I built three, but they really don't do much for dipoles. Good luck!

rw

poppachubby
10-22-2009, 12:36 AM
Looks good. The media racks on the left wall provide diffusion and the wall hanging behind the speaker provide absorption. You might try slightly less speaker toe-in though. Too much can narrow the stage width.

Here's (http://www.geocities.com/jonrisch/a3.htm) a DIY formula for building your own room lenses. I built three, but they really don't do much for dipoles. Good luck!

rw


I'll post the results E. I have a rack for my gear that I crafted myself. It's currently at my work until I am able to transport it home. As far as the angle goes, I thought I was following Cardas cube model which basically has the speakers pointed at the dome of the listener. I'll play around with it and see what results I get.

I'm way happier with this set up. Previously I was working from the corner-out. I had the speakers on either side of the comp. Now the soundstage is much more full, clearly there was a gap in the previous config. I will now spend some time listening to see where the weaknesses lie. E-Stat, should I only concern myself with results from my listening seat, or from other points in the room as well?

One more question though, with the media racking. Should there not be symmetrical diffusion for the opposite side of the room? I was actually worried about this...

BTW, I guess you didn't notice the plant in the photo. It was my nod to you since you seem to give props to your ficus a few times. I prefer the sonic abilities of a hibiscus myself.

E-Stat
10-22-2009, 05:21 AM
As far as the angle goes, I thought I was following Cardas cube model which basically has the speakers pointed at the dome of the listener.
I'm not sure where you looked, but here is the document found on George Cardas' site:

Cardas Speaker setup (http://www.cardas.com/pdf/roomsetup.pdf)

You'll note there is ZERO toe in as indicated by several drawings.


should I only concern myself with results from my listening seat, or from other points in the room as well?
Tonal balance will necessarily differ at various points in the room. You can rarely optimize them all! Another rule of thumb relates to optimum bass response. Typically, one finds nulls in the center of the room. Consequently, avoid placing your main seating area at the room's midpoint. Move closer to the speakers or further back. I optimized my listening position based on this fore-aft rule. Here again, the rule of thirds applies as well. I sit at approximately two-thirds of the room length.


One more question though, with the media racking. Should there not be symmetrical diffusion for the opposite side of the room? I was actually worried about this...
Not necessarily. Asymmetry can be a good thing.


BTW, I guess you didn't notice the plant in the photo. It was my nod to you since you seem to give props to your ficus a few times. I prefer the sonic abilities of a hibiscus myself.
Hibiscus, huh. LOL! The particular value of diffusing the first reflection points is helpful when speaker placement is on the short wall and they are relatively close to the wall. You want the first "bounce" from that side wall to be controlled. With your long wall placement, that really doesn't apply. Also, they need to be slightly forward of the speaker plane in order to work.

rw

poppachubby
10-22-2009, 08:37 AM
Well it looks like the hibiscus will serve no assistance to the room. Oh well, still looks nice. I am quite happy to find out that my room is thus far not too far off the mark. Of course, when I say this, I am speaking from my own point of view. I can only go so far with the treatment in my space.

My seat is actually about 1/3 back, off of center for sure. I will be sure to straighten out the speakers promptly. Now that I have some good beginnings, I can listen, enjoy and tweak the room with some fun additions. I will start with the room lens I think. I also need to EQ this new set up.

Thanks again E-Stat, I am enjoying this new dimension to my listening.