I have a serious bass canceling problem in my control room since i bought a pair of dynaudios that goes down to 30hz...
my control room is ca 4.2x3.8m with steep ceiling going from 3-2 m you can c it: http://www.lowswing.de/05plan/plan.html
in my studio only the rare two corners are 90° therefor it is easy to hang there bass traps is it enough if i treat only this corner with lates say 6 real traps or must i spread them around the room?
thanks
guy
bass traps on all 4 corners?
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lowswing
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bass traps on all 4 corners?
Guy Sternberg
Producer, Recording Engineer
LowSwing studios, Berlin
Producer, Recording Engineer
LowSwing studios, Berlin
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knightfly
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Before you even start placing traps, you need to assess room dimensions, speaker placement and your head location within the room - you don't give any dimensions so it's difficult to say what your problems may be - it's not even clear which way your ceiling is sloped; up to the rear or down to the rear, or even up to the right or left.
Things to look out for - don't put speakers at sideways positions that are even fractions of the width of the room at that plane - not 1/2, not 1/3, not 1/4, not 2/3, etc - same goes for front to back location of speakers or your head. Also, do NOT put speakers or ears at center of the distance between floor and ceiling - avoid this spot by at least 3-4 inches. Check out the wall bounce calculator on this forum for more ideas.
If you can do a more detailed drawing of your CR, I can explain more about placement options - as far as traps go, corners are your best bet. However, if your speakers or head are already placed in either peaks or nulls, traps can't do the whole job... Steve
Things to look out for - don't put speakers at sideways positions that are even fractions of the width of the room at that plane - not 1/2, not 1/3, not 1/4, not 2/3, etc - same goes for front to back location of speakers or your head. Also, do NOT put speakers or ears at center of the distance between floor and ceiling - avoid this spot by at least 3-4 inches. Check out the wall bounce calculator on this forum for more ideas.
If you can do a more detailed drawing of your CR, I can explain more about placement options - as far as traps go, corners are your best bet. However, if your speakers or head are already placed in either peaks or nulls, traps can't do the whole job... Steve
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Ethan Winer
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Re: bass traps on all 4 corners?
Guy,
> in my studio only the rare two corners are 90° <
I agree with Steve that it will help to know the room dimensions.
That said, besides the regular wall-wall corners, bass traps are also good in the corners at the tops of the walls where they meet the ceiling. And if a corner is not 90 degrees, it's still a valid place for bass traps.
--Ethan
> in my studio only the rare two corners are 90° <
I agree with Steve that it will help to know the room dimensions.
That said, besides the regular wall-wall corners, bass traps are also good in the corners at the tops of the walls where they meet the ceiling. And if a corner is not 90 degrees, it's still a valid place for bass traps.
--Ethan
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lowswing
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thanks for the help!
so as i said my room is ca 4.2x3.8m the celing is ca 3m behind listening position (the back of the room) and getting to ca 2m at the window to the live room.
my listen position is that the long wall is paralel to the live room window and i'm facing it.
what would be ,in my room, the best distance between the speakers (and to me) and where is the spot i should be monitor from?
so as i said my room is ca 4.2x3.8m the celing is ca 3m behind listening position (the back of the room) and getting to ca 2m at the window to the live room.
my listen position is that the long wall is paralel to the live room window and i'm facing it.
what would be ,in my room, the best distance between the speakers (and to me) and where is the spot i should be monitor from?
Guy Sternberg
Producer, Recording Engineer
LowSwing studios, Berlin
Producer, Recording Engineer
LowSwing studios, Berlin
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lowswing
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Ethan Winer
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Guy,
> as i said my room is ca 4.2x3.8m <
Sorry, I missed that! Okay, new question: How far behind you is the back wall?
That's a pretty small room, so I'm sure the low frequency nulls are caused by reflections off the wall behind you. You really do need bass traps in as many corners as possible, and optionally on the entire rear wall. And you'll still never achiece a perfectly flat response. Even million dollar control rooms have peaks and nulls, and those rooms are much larger than the space you have, and the walls are farther away from the mix position. This is the real issue - your close proximity to the walls and the reflections from those walls.
--Ethan
> as i said my room is ca 4.2x3.8m <
Sorry, I missed that! Okay, new question: How far behind you is the back wall?
That's a pretty small room, so I'm sure the low frequency nulls are caused by reflections off the wall behind you. You really do need bass traps in as many corners as possible, and optionally on the entire rear wall. And you'll still never achiece a perfectly flat response. Even million dollar control rooms have peaks and nulls, and those rooms are much larger than the space you have, and the walls are farther away from the mix position. This is the real issue - your close proximity to the walls and the reflections from those walls.
--Ethan
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lowswing
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knightfly
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There are a few possible problems I see, but need more measurements to be sure - your drawing shows the side walls being splayed inward at the front but no dimension given for width where your speakers are located - also no mention of speaker height (to center of woofer) or your head height - I'm assuming that with your head just slightly ahead of center that the ceiling height at your head is ca 2.4 meters?
There is a handy axial mode calculator at harmon's site that I use to find approximate locations for ears and speakers, but if you're having problems with Excel it may not work for you. Basically, what I do to get a rough idea is to draw the room to scale using the Paint program that comes with Windows - it allows you to do crude drawings and scale them if you watch the pixel coordinates in the lower right corner. I draw the room, then open another instance of Paint and import the graphic from this mode calculator, then re-size the graphic to match the room dimensions, paste the graph next to the room drawing, and finally add red lines at all the places NOT to put things and green lines at the GOOD places -
This sounds even more complex than it is, but if you will measure your front wall, and ceiling height directly over your head, I will assume your gear is centered left to right (it should be) and draw your room - then I'll add a grid showing good and bad placement, and you can try some of these changes for yourself.
Basically, you do NOT want either your ears or speakers to be located at even fractions of any dimension except the width; your head needs to be centered left to right, but NOT in any OTHER plane or you will get serious nulls and peaks in response - same goes for speakers - they should not be at 1/3, 1/2, 1/4 of ANY room dimension including ceiling height .
This isn't nearly as confusing as it sounds; I'm just waking up after several 12-hour graveyard shifts, so any confusion is likely MY fault. If you post your exact room dimensions and heights to speakers, ceiling, ears, I'll do a graphic that will make things more understandable... Steve
There is a handy axial mode calculator at harmon's site that I use to find approximate locations for ears and speakers, but if you're having problems with Excel it may not work for you. Basically, what I do to get a rough idea is to draw the room to scale using the Paint program that comes with Windows - it allows you to do crude drawings and scale them if you watch the pixel coordinates in the lower right corner. I draw the room, then open another instance of Paint and import the graphic from this mode calculator, then re-size the graphic to match the room dimensions, paste the graph next to the room drawing, and finally add red lines at all the places NOT to put things and green lines at the GOOD places -
This sounds even more complex than it is, but if you will measure your front wall, and ceiling height directly over your head, I will assume your gear is centered left to right (it should be) and draw your room - then I'll add a grid showing good and bad placement, and you can try some of these changes for yourself.
Basically, you do NOT want either your ears or speakers to be located at even fractions of any dimension except the width; your head needs to be centered left to right, but NOT in any OTHER plane or you will get serious nulls and peaks in response - same goes for speakers - they should not be at 1/3, 1/2, 1/4 of ANY room dimension including ceiling height .
This isn't nearly as confusing as it sounds; I'm just waking up after several 12-hour graveyard shifts, so any confusion is likely MY fault. If you post your exact room dimensions and heights to speakers, ceiling, ears, I'll do a graphic that will make things more understandable... Steve
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lowswing
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thanks knightfly,
I made 2 jpgs: "room" the plan from above and "side room" from the side, hope you'll have the time to help me couse i can't figure it out...
I wrote all important messurments on the pictures but here are some again (since i missed led you with completly wrong numbers before...):
room size 4.33x3.82m(longest point to widest point) hight=3.52m on back of the room going down to 2.70m where the window to studio room is.
my mixing position is 165cm from rare wall and 123 above the floor (the cieling in this point is 3m from the floor) , the speakr (center of woofer) is 118 above the floor (the hieght of the room there is 278cm). speakers are 175cm apart and from mix position.
thanks again
guy
I made 2 jpgs: "room" the plan from above and "side room" from the side, hope you'll have the time to help me couse i can't figure it out...
I wrote all important messurments on the pictures but here are some again (since i missed led you with completly wrong numbers before...):
room size 4.33x3.82m(longest point to widest point) hight=3.52m on back of the room going down to 2.70m where the window to studio room is.
my mixing position is 165cm from rare wall and 123 above the floor (the cieling in this point is 3m from the floor) , the speakr (center of woofer) is 118 above the floor (the hieght of the room there is 278cm). speakers are 175cm apart and from mix position.
thanks again
guy
Guy Sternberg
Producer, Recording Engineer
LowSwing studios, Berlin
Producer, Recording Engineer
LowSwing studios, Berlin
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lowswing
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Hi spent last night trying to figure out the modes drowing after I found the right link http://www.harman.com/wp/index.jsp?articleId=131
it took some time but i "mapped" my control room good point and bad point and I found out my speakers where standing in really bad place...
I've been today in the studio and changed the speakers location and my placment and the diffrent was NOT subtle! thanks a lot knightfly you mad my day!!! got really nice full bass that I was excepting from the dynaudio and the stereo image seem to be better (well in the new placment the speakers are spread abit more).
thanks again
it took some time but i "mapped" my control room good point and bad point and I found out my speakers where standing in really bad place...
I've been today in the studio and changed the speakers location and my placment and the diffrent was NOT subtle! thanks a lot knightfly you mad my day!!! got really nice full bass that I was excepting from the dynaudio and the stereo image seem to be better (well in the new placment the speakers are spread abit more).
thanks again
Guy Sternberg
Producer, Recording Engineer
LowSwing studios, Berlin
Producer, Recording Engineer
LowSwing studios, Berlin
-
Ethan Winer
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- Joined: Fri Feb 21, 2003 3:50 am
- Location: New Milford, CT, USA
- Contact:
Guy,
> wall is 2m behind my mixing positin <
That gives nulls at 50 Hz, 100 Hz, 150 Hz, and so forth.
I'd never minimize the importance of room modes, but 1/4 wavelength cancellation from the rear wall is even more significant in small rooms like yours. Finding the ideal speaker and listener placement will help, but your only hope to really improve things is by adding bass traps.
--Ethan
> wall is 2m behind my mixing positin <
That gives nulls at 50 Hz, 100 Hz, 150 Hz, and so forth.
I'd never minimize the importance of room modes, but 1/4 wavelength cancellation from the rear wall is even more significant in small rooms like yours. Finding the ideal speaker and listener placement will help, but your only hope to really improve things is by adding bass traps.
--Ethan
-
Ethan Winer
- Senior Member
- Posts: 1063
- Joined: Fri Feb 21, 2003 3:50 am
- Location: New Milford, CT, USA
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Steve,
> how did you calculate that? <
Where you been, Siberia?
Actually, I goofed slightly because the nulls are at every other multiple, not every multiple.
I did get it right in my Recording Spaces article in EQ magazine.
I rounded off the 2 meters, but basically there's a null at 1/4 wavelength and its odd multiples (3/4, 5/4, 7/4) in front of the rear wall, assuming the speakers are across the room facing that wall. So:
2 meters = 79 inches = 6.6 feet
times 4 = 26.3 feet for one full wavelength
1130 / 26.3 = 42.9 Hz
When you listen or measure 2 meters in front of the rear wall, the first null is at 42.9 Hz, the next is at 128.7 Hz, the next at 214.5 Hz, and so forth at (2 x 42.9) = 85.8 Hz multiples.
--Ethan
> how did you calculate that? <
Where you been, Siberia?
Actually, I goofed slightly because the nulls are at every other multiple, not every multiple.
I did get it right in my Recording Spaces article in EQ magazine.I rounded off the 2 meters, but basically there's a null at 1/4 wavelength and its odd multiples (3/4, 5/4, 7/4) in front of the rear wall, assuming the speakers are across the room facing that wall. So:
2 meters = 79 inches = 6.6 feet
times 4 = 26.3 feet for one full wavelength
1130 / 26.3 = 42.9 Hz
When you listen or measure 2 meters in front of the rear wall, the first null is at 42.9 Hz, the next is at 128.7 Hz, the next at 214.5 Hz, and so forth at (2 x 42.9) = 85.8 Hz multiples.
--Ethan