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foreverain4
New member
TexRoadkill
Audio Bum
Just straighten out the slats and vary the slat spacing and widths and you have a helmholtz resonator.
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foreverain4
New member
by doing the angles, wouldnt i get some diffusion as well? i could vary the spaces and still keep them slanted. or is that defeating the purpose?
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foreverain4
New member
i guess, even if they are flat, i still get diffusion, correct?
knightfly
GrouchyOldFartOnBatteries
You haven't really stated the purpose - things like the size of the room (all three dimensions) where you intend to put them, what you hope to accomplish, what the actual angles between the slats are, etc - for example, if the angles between the slats are exactly 90 degrees, then for anything above approximately 300 hZ, any sound that enters the device will be reflected right back parallel to the entry angle. This is true of any 90 degree angle corner. Using separate slats for the front negates most, if not all, the resonance effect that makes a panel bass trap work - slots between the slats will tend to act as a helmholz, but unless you put some kind of restriction behind the slots it won't be much.
If your room is actually big enough to benefit from diffusion instead of absorption, it would be simpler to build polycylindrical absorber/diffusors than it would to mess with all those slats and angles, and it would work better.
Maybe if you explained more of your circumstances, like room size/function/shape, and what you hope to accomplish... Steve
If your room is actually big enough to benefit from diffusion instead of absorption, it would be simpler to build polycylindrical absorber/diffusors than it would to mess with all those slats and angles, and it would work better.
Maybe if you explained more of your circumstances, like room size/function/shape, and what you hope to accomplish... Steve
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foreverain4
New member
http://www.therecordinghouse.com/Studio.html
i am lookin at the live room. it is roughly 38 ft. x 33 ft. with 10 ft. 6 in. ceilings. i have been using auralex products for the last year and i am ready to do something a bit more professional. i have seen that detail for the cylindrical diffusor. looks interesting..
i am lookin at the live room. it is roughly 38 ft. x 33 ft. with 10 ft. 6 in. ceilings. i have been using auralex products for the last year and i am ready to do something a bit more professional. i have seen that detail for the cylindrical diffusor. looks interesting..
knightfly
GrouchyOldFartOnBatteries
With a room that size you could definitely use a diffusive wall - one example of what it could look like can be found on Sunday TV - check out America's Funniest Videos, and the dramatic poly wall they use on that set. Larger sections work about the same, in fact full 4 x 8 sheets bowed into slotted cleats can also be used. Check out Everest's Master Handbook for a few drawings on that.
One other thing that caught my eye on your site was the nearfields laid on their side - you might try setting them upright and seeing if you notice a wider sweet spot. The only acoustic reason NOT to upright them would be if there were flush mounted mains behind them and you didn't want to screw up the imaging of the mains... Steve
One other thing that caught my eye on your site was the nearfields laid on their side - you might try setting them upright and seeing if you notice a wider sweet spot. The only acoustic reason NOT to upright them would be if there were flush mounted mains behind them and you didn't want to screw up the imaging of the mains... Steve
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foreverain4
New member
you mentioned making one wall diffusive, which one would you go for? the primary use of this specific rooms is tracking drums and vocal groups. should i just pick one? most of my other tracking is done in the iso boothe..
knightfly
GrouchyOldFartOnBatteries
I'd need quite a bit more info before suggesting what changes should be made - like is that drum area just a riser, if so how's it made, is the wall (the one behind the drums) that's 90 degrees to the control room window also as reflective as the window, do you use a stereo pair of overheads as part of the drum micing setup, what is the bunch of squiggly lines on the right side wall, what materials are floor and ceiling made of, but most of all what don't you like about your setup/sound as it is now?
Acoustics are tricky enough when you're in the room - long distance, they are even more difficult; so, any and all info you have about the existing setup and results would help... Steve
Acoustics are tricky enough when you're in the room - long distance, they are even more difficult; so, any and all info you have about the existing setup and results would help... Steve
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foreverain4
New member
knightfly said:
yes, the drum area is a riser. it has parque wood flooring on it. it is about 5" tall and is made with a 2x4 frame and 2x4 joists running across it. this is set on top of a carpeted floor. the wall at 90 is drywall. presently it is 100% covered with 2" foam. i use stereo overheads in xy. those lines on the right are just representing mic stands. the floor is basically carpet with some tile where the doors are and wood under the drums. the ceiling is actually 13 ft. high, it is lowered to 10 1/2 after installing a drop ceiling. the ceiling contains "acoustic" tiles. on top of those is a 10" layer of fiberglass insulation. i would like to be able do more distant micing for drums. if have tried this and it just sounds like crap.
knightfly
GrouchyOldFartOnBatteries
Your description, "it just sounds like crap." could apply to almost anything - just to get things more pinned down, I'm gonna make a wild guess here, see if I'm close at all: When you pull your mics back, your drums/cymbals lose any "shimmer" they had, and drums sound like you maybe put a medium-weight blanket over them. I'll go one more; group acapella vocals, if they work at all, need a fair amount of treble boost to have any "air" to them.
Is that anywhere in the ballpark? I made a couple assumptions about the rest of the room's treatment, so I'm not sure on anything yet.
Your actual modal distribution, using dim's of 38,33, and 13 feet, looks pretty good down to 30 hZ - below that there's a slight dip but most speakers wouldn't even reproduce it, and you definitely wouldn't hear it with what I'm seeing on the bridge. Are you using a sub with your nearfields, or am I missing something? Your site doesn't even mention a monitoring system, so I'm not sure what you're using.
Is your drum riser filled with insulation, or hollow between the framing?
If you can fill in the blanks including what's on the rest of the walls in the tracking room, and let me know if I'm close to what your perceived problem is... Steve
Oh, just in case you're not already doing so, be sure and keep your mics away from heights that are either half of your REAL ceiling height, or half of your LOWERED ceiling height by at least 4-6" - that can cause several nulls in response too...
Is that anywhere in the ballpark? I made a couple assumptions about the rest of the room's treatment, so I'm not sure on anything yet.
Your actual modal distribution, using dim's of 38,33, and 13 feet, looks pretty good down to 30 hZ - below that there's a slight dip but most speakers wouldn't even reproduce it, and you definitely wouldn't hear it with what I'm seeing on the bridge. Are you using a sub with your nearfields, or am I missing something? Your site doesn't even mention a monitoring system, so I'm not sure what you're using.
Is your drum riser filled with insulation, or hollow between the framing?
If you can fill in the blanks including what's on the rest of the walls in the tracking room, and let me know if I'm close to what your perceived problem is... Steve
Oh, just in case you're not already doing so, be sure and keep your mics away from heights that are either half of your REAL ceiling height, or half of your LOWERED ceiling height by at least 4-6" - that can cause several nulls in response too...
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foreverain4
New member
knightfly said:
pretty much nails it
knightfly said:
using alesis monitor 1's mkII. yes i do have a sub as well. my control room must not be to bad as my mixs translate very well.
knightfly said:
the drum riser is hollow between the studs
knightfly said:
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Pahtcub
New member
You have a chess board in the control room??? FREAKING SWEET!!!!!
Pat
Pat
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foreverain4
New member
Pahtcub said:
yes i do actually. it is built right in to the octagon table. it is bar height so i have bar stools around it.
knightfly
GrouchyOldFartOnBatteries
Sorry I've not gotten back on this yet - gotta work 12-hour graveyard shifts thru New years, so I'm kinda wiped for anything fun - Need one more answer - "If you can fill in the blanks including what's on the rest of the walls in the tracking room" -
Meantime, two things I'd look at are getting some 6" fiberglas batt insulation for your drum riser; if you can tilt it up vertical (prob'ly wanna take the drums off it first :=) and staple the paper side of the insulation to the bottoms of the joists, so the fluffy part rests against the underside of the top surface - this should fix any resonance you are likely getting from the un-damped floor of the riser.
Then, if you can get hold of enough plastic sheeting (preferably around .006", like they use to cover hay in winter) and lay the plastic out across all that carpet, then try your distance micing again and see how much difference it makes. It should be pretty noticeable, but since I don't yet know how much more foam you have on the other walls I can't say just how much difference.
That test is probably the cheapest and easiest way to find out if you want to ditch the carpet altogether - my guess would be "yes"... keep in mind that the sound won't be exactly the same with plastic as without the carpet, just brighter, and closer to a bare wood floor. A wood floor should give you even more high mids back than the plastic covered carpet.
Some gobos and/or movable/reversible treatments on cleats on the walls would let you "dial in" different degrees of brightness/diffusion too, we can talk about that in a day or two if you're into it... Steve
Catch you in a day or two when I'm half alive again... Steve
Meantime, two things I'd look at are getting some 6" fiberglas batt insulation for your drum riser; if you can tilt it up vertical (prob'ly wanna take the drums off it first :=) and staple the paper side of the insulation to the bottoms of the joists, so the fluffy part rests against the underside of the top surface - this should fix any resonance you are likely getting from the un-damped floor of the riser.
Then, if you can get hold of enough plastic sheeting (preferably around .006", like they use to cover hay in winter) and lay the plastic out across all that carpet, then try your distance micing again and see how much difference it makes. It should be pretty noticeable, but since I don't yet know how much more foam you have on the other walls I can't say just how much difference.
That test is probably the cheapest and easiest way to find out if you want to ditch the carpet altogether - my guess would be "yes"... keep in mind that the sound won't be exactly the same with plastic as without the carpet, just brighter, and closer to a bare wood floor. A wood floor should give you even more high mids back than the plastic covered carpet.
Some gobos and/or movable/reversible treatments on cleats on the walls would let you "dial in" different degrees of brightness/diffusion too, we can talk about that in a day or two if you're into it... Steve
Catch you in a day or two when I'm half alive again... Steve
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foreverain4
New member
the walls are about 50% covered with auralex 2" studio foam. i did checker board type placement. i offset the paralell walls so that directly across from a 2' x 2' piece, there is bare wall. it is pretty acurrate as i used my ceiling tiles for alignment.
you mean to tell me that putting plastic on the floor can sort of "simulate" a hardwood floor? weird.
thanks for your time.
you mean to tell me that putting plastic on the floor can sort of "simulate" a hardwood floor? weird.
thanks for your time.
knightfly
GrouchyOldFartOnBatteries
The key word there is "sort of" - the plastic will reduce the amount of high frequency absorption by the carpet, but not so much at lower frequencies. I don't have any hard data as to where in the frequency range the effect starts to decrease.
Everest makes this point in his Master Handbook, but in a different context - he points out that Kraft-faced insulation can be installed either way inside a wall with no noticeable difference, but when the same insulation is surface mounted it's VERY noticeable at higher frequencies whether the Kraft facing is out (brighter) or the fiberglas surface is out (absorbs more highs)
I would have suggested laying sheets of plywood down for the test, but at over $10 per sheet that would be pretty expensive way to find out you didn't like it.
With staggered, 50% coverage on your walls you're probably close to optimum without using something other than foam. Your parallel walls would likely need that much coverage to avoid flutter echo. The next step would be to try either standing about half your foam panels off the wall by a few inches, possibly by adding 2 to 4" rigid fiberglas or rockwool panels either behind or instead of those foam panels. This would partially depend on what look you want. Either of the rigid insulations would have to be "contained", by wrapping each piece in thin plastic (absorbs less highs so room stays brighter, also keeps glass fibers controlled) and then wrapped in your choice of cloth cover for aesthetics.
If, with plastic over the carpet, you hear more mids and high mids than seems balanced, doing the changes in the preceding paragraph incrementally til you're happy would be a way to go. There's also the "rail" approach for variable acoustics, one method of which I drew for Ruzo -
http://www.homerecording.com/bbs/showthread.php?s=&threadid=108011
Gotta go see if I can get my snow tires on before work, crap I hate snow - stuff oughta stay put so you could drive to it when YOU want it... Steve
Everest makes this point in his Master Handbook, but in a different context - he points out that Kraft-faced insulation can be installed either way inside a wall with no noticeable difference, but when the same insulation is surface mounted it's VERY noticeable at higher frequencies whether the Kraft facing is out (brighter) or the fiberglas surface is out (absorbs more highs)
I would have suggested laying sheets of plywood down for the test, but at over $10 per sheet that would be pretty expensive way to find out you didn't like it.
With staggered, 50% coverage on your walls you're probably close to optimum without using something other than foam. Your parallel walls would likely need that much coverage to avoid flutter echo. The next step would be to try either standing about half your foam panels off the wall by a few inches, possibly by adding 2 to 4" rigid fiberglas or rockwool panels either behind or instead of those foam panels. This would partially depend on what look you want. Either of the rigid insulations would have to be "contained", by wrapping each piece in thin plastic (absorbs less highs so room stays brighter, also keeps glass fibers controlled) and then wrapped in your choice of cloth cover for aesthetics.
If, with plastic over the carpet, you hear more mids and high mids than seems balanced, doing the changes in the preceding paragraph incrementally til you're happy would be a way to go. There's also the "rail" approach for variable acoustics, one method of which I drew for Ruzo -
http://www.homerecording.com/bbs/showthread.php?s=&threadid=108011
Gotta go see if I can get my snow tires on before work, crap I hate snow - stuff oughta stay put so you could drive to it when YOU want it... Steve
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foreverain4
New member
a few more pics of the live room so you get a better idea of what is going on....
http://www.therecordinghouse.com/Studio.html
http://www.therecordinghouse.com/Studio.html
knightfly
GrouchyOldFartOnBatteries
Have you listened to any mixes since rotating the Monitor One's? Specifically, if you have them on their side and move around over the console like you're reaching for faders, you should notice more of a "phasing" sound than if you do the same test with the monitors vertical. Your head moves more side to side than vertical (normally, anyway) so mounting the tweets above the woofers causes less phase changes between drivers when you're moving from side to side. Some people don't mind or notice it, others do.
Do you know what your actual interior wall construction is, exactly? I'm not seeing any sign of traps other than the foam. Chances of the room having a uniform reverb time under those conditions would be pretty slim.
From what I can see, I would stick by my recommendations so far - insulate the riser as I suggested, get some plastic and see if you like the sound better, do some broadband traps in at least a couple of the corners, and re-evaluate the sound.
One other thing that may be affecting drum tracks - your CR window and the area around it. Makes it impossible to get a balanced stereo track with your overheads. One way to fix this would be to put some glass or plexi "louvers" in front of the window, tilted so that they reflect sound up to the ceiling - that way, you can still see through them but the reflections are controlled.
Those are the main things I'd look at for now... Steve
Do you know what your actual interior wall construction is, exactly? I'm not seeing any sign of traps other than the foam. Chances of the room having a uniform reverb time under those conditions would be pretty slim.
From what I can see, I would stick by my recommendations so far - insulate the riser as I suggested, get some plastic and see if you like the sound better, do some broadband traps in at least a couple of the corners, and re-evaluate the sound.
One other thing that may be affecting drum tracks - your CR window and the area around it. Makes it impossible to get a balanced stereo track with your overheads. One way to fix this would be to put some glass or plexi "louvers" in front of the window, tilted so that they reflect sound up to the ceiling - that way, you can still see through them but the reflections are controlled.
Those are the main things I'd look at for now... Steve
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