Topic: Room Mode calculator?

[Chuck]

I used to have all this info, but I don't anymore...

I recently moved things around in my DAW room and I'm not happy with the placement of my speakers anymore. Now, there is a big bump at 175 Hz at my listening position.   And a big null at 150 Hz 

I seem to remember a calculator that help with placement of speakers to reduce room nodes. If someone has the info on where to find that calculator, I'd appreciate it.

My room is 12' x 10' x 8' high. Far from ideal...
Currently I am faced into a corner on a U shaped desk, which I realize is not ideal, either...
I pulled the desk away from the walls recently, so there is 20" between the back of the speakers and each wall.

[Church-Audio]

I used to have all this info, but I don't anymore...

I recently moved things around in my DAW room and I'm not happy with the placement of my speakers anymore. Now, there is a big bump at 175 Hz at my listening position.   And a big null at 150 Hz 

I seem to remember a calculator that help with placement of speakers to reduce room nodes. If someone has the info on where to find that calculator, I'd appreciate it.

My room is 12' x 10' x 8' high. Far from ideal...
Currently I am faced into a corner on a U shaped desk, which I realize is not ideal, either...
I pulled the desk away from the walls recently, so there is 20" between the back of the speakers and each wall.

What I do with studio monitors is first get them off the big surface. Second get them at ear level so the tweeter is at your ear height. Then I make sure that there is very good isolation between the speaker and your desk. I think some of your resonance might be sympathetic resignation of your desk. So if you can get the speakers higher, I would suggest that. I would get some good stands for them or make a big shelf and attach it to your wall but again make sure its solid then isolate your speakers with a monitor pad they can be purchased for $30-200 a pair and make a huge difference.

[Chuck]

I used to have all this info, but I don't anymore...

I recently moved things around in my DAW room and I'm not happy with the placement of my speakers anymore. Now, there is a big bump at 175 Hz at my listening position.   And a big null at 150 Hz 

I seem to remember a calculator that help with placement of speakers to reduce room nodes. If someone has the info on where to find that calculator, I'd appreciate it.

My room is 12' x 10' x 8' high. Far from ideal...
Currently I am faced into a corner on a U shaped desk, which I realize is not ideal, either...
I pulled the desk away from the walls recently, so there is 20" between the back of the speakers and each wall.

What I do with studio monitors is first get them off the big surface. Second get them at ear level so the tweeter is at your ear height. Then I make sure that there is very good isolation between the speaker and your desk. I think some of your resonance might be sympathetic resignation of your desk. So if you can get the speakers higher, I would suggest that. I would get some good stands for them or make a big shelf and attach it to your wall but again make sure its solid then isolate your speakers with a monitor pad they can be purchased for $30-200 a pair and make a huge difference.

Thanks, Chris. I did a bunch of reading a while ago, when I first put the room together. Recently I had to change things around. I do have the monitors at the proper height. I'm thinking I'll have to add some room treatment, if I keep things the way they are now.

I noticed the problem after Rodney (Steam Powered) brought over his Schoeps sub-cardiod recording of Big Head Todd and the Monsters. On my DAW it sounded very muddy. It sounded fine in my car and on my big system in the living room. So, I got out the flatest omni mic I have, and recorded pink noise played through the speakers and placed the mic at my listening position. In WaveLab's spectum analyser I saw the very obvious anamolies at 175 Hz and 150Hz. I figure it's standing waves caused by moving the placement of the desk, and in turn, my listening positon,  in the room.

Now, I am on quest to find the best place for everything. So far the only "room treatments" I have are carpet on the floor, a futon against one wall and a couple of mexican blankets on the wall behind the monitors.


edit.

Oh yeah, the monitors are raised above the desk on a riser I built, so there is nothing but air, in front of them.

[Church-Audio]

I used to have all this info, but I don't anymore...

I recently moved things around in my DAW room and I'm not happy with the placement of my speakers anymore. Now, there is a big bump at 175 Hz at my listening position.   And a big null at 150 Hz 

I seem to remember a calculator that help with placement of speakers to reduce room nodes. If someone has the info on where to find that calculator, I'd appreciate it.

My room is 12' x 10' x 8' high. Far from ideal...
Currently I am faced into a corner on a U shaped desk, which I realize is not ideal, either...
I pulled the desk away from the walls recently, so there is 20" between the back of the speakers and each wall.

What I do with studio monitors is first get them off the big surface. Second get them at ear level so the tweeter is at your ear height. Then I make sure that there is very good isolation between the speaker and your desk. I think some of your resonance might be sympathetic resignation of your desk. So if you can get the speakers higher, I would suggest that. I would get some good stands for them or make a big shelf and attach it to your wall but again make sure its solid then isolate your speakers with a monitor pad they can be purchased for $30-200 a pair and make a huge difference.

Thanks, Chris. I did a bunch of reading a while ago, when I first put the room together. Recently I had to change things around. I do have the monitors at the proper height. I'm thinking I'll have to add some room treatment, if I keep things the way they are now.

I noticed the problem after Rodney (Steam Powered) brought over his Schoeps sub-cardiod recording of Big Head Todd and the Monsters. On my DAW it sounded very muddy. It sounded fine in my car and on my big system in the living room. So, I got out the flatest omni mic I have, and recorded pink noise played through the speakers and placed the mic at my listening position. In WaveLab's spectum analyser I saw the very obvious anamolies at 175 Hz and 150Hz. I figure it's standing waves caused by moving the placement of the desk, and in turn, my listening positon,  in the room.

Now, I am on quest to find the best place for everything. So far the only "room treatments" I have are carpet on the floor, a futon against one wall and a couple of mexican blankets on the wall behind the monitors.


edit.

Oh yeah, the monitors are raised above the desk on a riser I built, so there is nothing but air, in front of them.

You should make a mic out of one of the panasonic capsules I gave you a while back the wm-61 is very flat out to 15k and if you put it in a nice long brass tube and glue it together you will have your self a good measurement mic. For doing tests in the low end. Also you should be using MLS not pink noise for this type of measurement to get what your speakers are actually doing then use pink noise and fft to see how the room is changing the sound. MLS will help remove the room to a degree from the equation then you can use FFT to include the room this will tell you where your problems really are. I think in most cases that frequency tends to be a port problem, you said you were told to block the ports on your speakers? did you block them really good or did you gently stuff something into the port?


The other thing I would do is put on a really well mastered cd.. And listen to it. Not something that has been recorded live.

[Chuck]

I ran tests with the speaker ports open and the ports closed. The sound changed, but the anomolies were still there. I haven't added the subwoofer to the system yet. Actually, I always play a well mastered CD before I do any work on the DAW.

I just checked out the Auralex site. I plugged in my room dimensions and they recommeded $800 worth of their product! Yikes!

Ideally, I know what I should do...
Remove everything from the room. Place the speakers in various locations. Place the microphone in the listening position for each location and run noise tests. When I find a good spot, start adding furnature to see if anything changes.

[Church-Audio]

I ran tests with the speaker ports open and the ports closed. The sound changed, but the anomolies were still there. I haven't added the subwoofer to the system yet. Actually, I always play a well mastered CD before I do any work on the DAW.

I just checked out the Auralex site. I plugged in my room dimensions and they recommeded $800 worth of their product! Yikes!

Ideally, I know what I should do...
Remove everything from the room. Place the speakers in various locations. Place the microphone in the listening position for each location and run noise tests. When I find a good spot, start adding furnature to see if anything changes.

How far apart are they? The other thing you could do is what I do. I have a parametric eq on my speakers an Orban it was about $150 used and you should be able to bump down the problem with that.

I would also look at what you have on the floor a wooden floor with give you a nice 150 bump in most rooms. A rug can fix that. Discribe whats in the room for me.

Chris
Ps.. better yet take a picture.

[Chuck]

I ran tests with the speaker ports open and the ports closed. The sound changed, but the anomolies were still there. I haven't added the subwoofer to the system yet. Actually, I always play a well mastered CD before I do any work on the DAW.

I just checked out the Auralex site. I plugged in my room dimensions and they recommeded $800 worth of their product! Yikes!

Ideally, I know what I should do...
Remove everything from the room. Place the speakers in various locations. Place the microphone in the listening position for each location and run noise tests. When I find a good spot, start adding furnature to see if anything changes.

How far apart are they? The other thing you could do is what I do. I have a parametric eq on my speakers an Orban it was about $150 used and you should be able to bump down the problem with that.

I would also look at what you have on the floor a wooden floor with give you a nice 150 bump in most rooms. A rug can fix that. Discribe whats in the room for me.

Chris
Ps.. better yet take a picture.

10' x 12' x 8 feet high. Wall to wall carpeted. The speakers are ~42" apart and my listening position is ~42" from each speaker. I had to move things around a bit to make my wife happy... But it doesn't sound as good, as it used to.

I'm about to give up on making her happy though, as the new configuration isn't working well for me. Part of the problem is that I have a U shaped desk. If I bought or built a straight desk, I could set up along a wall, rather than in a corner.

I will take pictures tonight.

[Chuck]

I found that Room Mode Calculator. It's in the attached zip file.

[Chuck]

Pics of my DAW room...

[Church-Audio]

Pics of my DAW room...

I would increase the padding behind your hanging rugs. I would also isolate the speakers from the shelf. Thats the first step.

[Chuck]

+T, and thanks for the tips, Chris. I have some rubber mats under each speaker. I also have a roll of rock wool that I will use as an absorber. I am going to try moving things around, a bit, to see if that makes a difference, too.

[cshepherd]

I'm pretty sure Rockwool is hazardous to breath.  A couple of isolation products that aren't very expensive are Vibrapod isolation pods ($25 per four pack) and Aurelex isolation pads (~$30 -$50 each).  We sell Vibrapods, the Aurlex products can be found in Guitar Centers and the like.  Keep in mind your speakers are in a corner.  That's about the worst spot in the room for them.  Bass collects in the corner behind them and muddies everything up.  Isolating the speakers will help, but you are trying to overcome serious speaker placement issues.  If the speaker is ported, try sealing the port with a sock.  Another trick is to offset the speakers from the corner.  Have one speaker closer to the corner than the other instead of the speakers being equidistant from the corner of the room.

Chris

[Chuck]

I'm pretty sure Rockwool is hazardous to breath.  A couple of isolation products that aren't very expensive are Vibrapod isolation pods ($25 per four pack) and Aurelex isolation pads (~$30 -$50 each).  We sell Vibrapods, the Aurlex products can be found in Guitar Centers and the like.  Keep in mind your speakers are in a corner.  That's about the worst spot in the room for them.  Bass collects in the corner behind them and muddies everything up.  Isolating the speakers will help, but you are trying to overcome serious speaker placement issues.  If the speaker is ported, try sealing the port with a sock.  Another trick is to offset the speakers from the corner.  Have one speaker closer to the corner than the other instead of the speakers being equidistant from the corner of the room.

Chris

Yeah, I used to have the whole desk reversed. The desk and speakers were in the middle of the room and I was in the corner. The speakers were directed at the corner. I thought it sounded better that way. I may have to go back to that. The other option is to get a new desk, and have the speakers/desk along the wall that is across from the window. That would place one of the speakers near a corner and the other one near a door.

[cshepherd]

Aurelex has some small pads made for computer speakers that are pretty nifty.  I don't know about their room treatments.  Having one speaker near a corner isn't that much of an issue as long as the speaker's not equidistant from both the rear and side wall.  Optimally, the speakers should be on decent stands, slightly away from the rear wall.  That will always be your best option for good sound.

Good Luck,
Chris

[RebelRebel]

Chuck, check out www.realtraps.com

www.ethanwiner.com

www.gikacoustics.com (I just treated my entire room for well, well less than 1G).. the guy there, Glenn Kuras, is a great person, and if you send him some pictures, he will tell you exactly how to outfit your room. The auralex stuff, in my opinion, is way overpriced, not as effective(I have used Auralex products in germany and here) , etc.... GIK is the way to go for treatment, without question. Top notch products for  small change..


john l sayers(very well known acoustic expert and room designer) forum is outstanding for info as well...  http://www.johnlsayers.com/phpBB2/index.php