Hi all.
ok i read eircs post and i would be thankful if if someone could clear up a a few questions i have.
were you saying that in a real life situation the thicker the rockwool does not really matter but its the gap between it and the wall?
if so what is the optium thickness for panel traps/slots and mounted straight on the wall. or does it relate to what frequenceies you want to absorb. i have the option of 1"/2" or 4" 100kg.
my preference is 2" for slots and panel traps
which leads me to my next question ,I didnt understand what you were saying about panel traps, were you sayin that their disadvantages outway thair advantages?
thanks
bryan
Fabrics & Rockwool Question
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Eric_Desart
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Hello Brian,
Since you started a new thread, I do assume here that you reffer to absorption.
If you respect the engineering ratios I gave in function of thickness (that is: Thickness material + cavity width) you will get about the same absorption as a material as thick as the sum of both.
However it's logical that one needs a certain thickness of the board itself too versus the wavelength. Therefor I gave a rule of thumb to define the thickness of the boeard itself too.
With lower densities i should say that 50 mm 2" should be a minimum (but also here the difference is minor)
Only measurements can give conclusive answers, but for slot type Helmholz, I should say you can use a comparable approach.
A panel trap is more specific, the amount of wool and exact positioning will influence the bahavior of the panel trap.
In fact for a panel trap and in a somewhat lesser degree a Helmholtz the wool act as a damper on an air cushion which is a spring, and which a different type of soundfield (pressure room) than standard absoroption.
But also here I think the rule of thumb is a save approach.
The density should not be 100 kg. Such a board in itself will act as a membrane damper. I should choose for lower densities. (fiberglass 35 to 50 kg and rockwool 45 to 65 kg).
In function of panel traps, I don't say that the disadvantages outweigh the advantages. I only say that one should take care of those side effects.
Ethan suggests panel traps anywhere.
John uses a lot slat type resonators (and wool for bastraps).
I preffer mainly wool but applied in such a manner that I only use linear absorption, and control mid and highs often in a different manner.
All 3 will or can get good results.
Resonators of any type (panel, Helmholtz) will influence transmission loss of drywall or other type of lightweight double leave systems, since they wittingly create a resonance in order to absorb this energy. This resonance interacts with the resonance of the mass-spring resonance.
Plain absorption by wool doesn't, it just absorbs energy as it is present.
But I directly admit: there is no such thing as THE exclusive good solution.
Kind regards
Eric
Since you started a new thread, I do assume here that you reffer to absorption.
It's both,Bryan wrote: were you saying that in a real life situation the thicker the rockwool does not really matter but its the gap between it and the wall?
bryan
If you respect the engineering ratios I gave in function of thickness (that is: Thickness material + cavity width) you will get about the same absorption as a material as thick as the sum of both.
However it's logical that one needs a certain thickness of the board itself too versus the wavelength. Therefor I gave a rule of thumb to define the thickness of the boeard itself too.
With lower densities i should say that 50 mm 2" should be a minimum (but also here the difference is minor)
,Bryan wrote: if so what is the optium thickness for panel traps/slots and mounted straight on the wall. or does it relate to what frequenceies you want to absorb. i have the option of 1"/2" or 4" 100kg.
bryan
Only measurements can give conclusive answers, but for slot type Helmholz, I should say you can use a comparable approach.
A panel trap is more specific, the amount of wool and exact positioning will influence the bahavior of the panel trap.
In fact for a panel trap and in a somewhat lesser degree a Helmholtz the wool act as a damper on an air cushion which is a spring, and which a different type of soundfield (pressure room) than standard absoroption.
But also here I think the rule of thumb is a save approach.
The density should not be 100 kg. Such a board in itself will act as a membrane damper. I should choose for lower densities. (fiberglass 35 to 50 kg and rockwool 45 to 65 kg).
In function of panel traps, I don't say that the disadvantages outweigh the advantages. I only say that one should take care of those side effects.
Ethan suggests panel traps anywhere.
John uses a lot slat type resonators (and wool for bastraps).
I preffer mainly wool but applied in such a manner that I only use linear absorption, and control mid and highs often in a different manner.
All 3 will or can get good results.
Resonators of any type (panel, Helmholtz) will influence transmission loss of drywall or other type of lightweight double leave systems, since they wittingly create a resonance in order to absorb this energy. This resonance interacts with the resonance of the mass-spring resonance.
Plain absorption by wool doesn't, it just absorbs energy as it is present.
But I directly admit: there is no such thing as THE exclusive good solution.
Kind regards
Eric
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John Sayers
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Eric_Desart
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Charles Dayton
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703 insulation & Material
I finally got my hands on some 1" 703 insulation and some lovely blue burlap. I was wondering, if anyone had a clue as to how to mount the cloth to the panels. Do I use spray adheasive or staple it to the back around the edges? Also, how far should I shim it out from the walls. I'm trying to create a dead end - live end situation for my mix room, which is 17' wide and 19' long. The ceiling slopes at an angle from 10' to 9' corner to corner, the low corner to the right of the mix position. The window to the recording room is right in front of the mixing desk. Should I bother to put up board below the window, which is below the desk? I,ve mixed in rooms that had hard surfaces up front and absorptive in the back, but that never made any sense to me because of the amount of early reflections directly in front of the console. They did, however have a cloud hanging directly over the mix position. I hope I have not rambled on too long.
Thanx for any help
Thanx for any help
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knightfly
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Charles, first I'd like to welcome you to the forum - and, you haven't seen rambling til you wade through some of our answers (OK, mine :=(
In order to keep the fronts of your 703 panels looking straight and un-wrinkled, one way would be to use a combination of your ideas. You can place the burlap on a flat surface, put the 703 down on the burlap, use about half a hand-print sized area at corners and middle of the long side, and stretch the burlap around to the glue area in back. If the adhesive you're using needs to be held in contact for a while, you can use boards with excercise weights or anything heavy to hold the burlap against the adhesive til it sets. Try to keep the weave of the burlap even at the first edge you glue, and then stretch the other side evenly according to weave lines as well - this will make the finished panels look more professional.
1" 703 seems a bit light for effective absorption, but it should help quite a bit if you space it from the wall - a 3" gap will cause it to absorb down to the same frequencies as 4", just not as MUCH absorption since the sound will have only 1/4 as far to travel through the fiberglas itself. For more absorption you could glue 2,3, or even 4 of the panels together before you wrapped them with the burlap.
If I'm correct in assuming that your room is rectangular except for the side-to-side slope of the ceiling, then modal distribution will be somewhat more important than if the room were set up as a Reflection-Free Zone - and, unfortunately, I just ran your dimensions in one of my spreadsheets and it's going to need some help.
Your average height of 9.5 feet is EXACTLY the same as the second harmonic of the length, so there are two different axes supporting several of the same frequencies. This can be really difficult, if not impossible, to correct for.
If it's not possible or practical to even out the ceiling by building it down to 9 feet all around, I would try mounting some of your 703 (spaced out 3") on sheets of plywood (1/2" should do) suspended (like clouds) over as much of the room as you can, (ESPECIALLY over the MIX area) hung level at either 8 or 9 feet (NOT 8.5, as that is half your 17 foot dimension) - The plywood will give you a "shell" effect, breaking up the modes that duplicate harmonics of the length, evening out the stereo field, and the 703 in front of the plywood will do what it always does, which is absorb early reflections off the ceiling.
The plywood can be suspended using eyebolts thru the plywood (before the 703 is applied) then those eye bolts can be hung from medium to heavy plant hooks in the ceiling, placed at the 4 corners and one in the center of each sheet of plywood. You can get HEAVY picture hanging wire, or LIGHT aircraft cable, at Home Depot for the long hangers, and go direct from plant hook to eyebolt on the shortest side (lowest part of the ceiling) Going direct from eyebolt to plant hook will require fairly careful measuring so they line up with each other.
As to LEDE plans, that kind of went out several years ago - it tended to make things too dead in the control room, plus you need a minimum of 12-15 feet behind your head before it's a good idea to leave the rear wall live. Otherwise, you get reflections off the back wall that are soon enough to cause phase cancellations/smearing in the stereo image.
Once you have the wall below the front window absorbed and the ceiling evened out, the next areas should be found with a mirror and a helper - basically, you move the mirror around held flat on all surfaces - anywhere you can see the speakers in the mirror from your mix position, you need absorption. These are the places I'd use multiple layers of the 1" 703, along with that front lower wall.
If you're using nearfields, depending on where you have them placed you also may get early reflections off your console surface, or even whatever shelves they are sitting on - use the mirror to check that as well; sometimes reflections off the console can't be helped, but other times people build their own desks and come up with ways around the console reflections - I'm working on plans for a mix desk that won't be level, but sloped slightly toward the front (once I finalize the rest of the details) to solve this.
See, and you thought YOU could ramble - I hope some of this was helpful... Steve
In order to keep the fronts of your 703 panels looking straight and un-wrinkled, one way would be to use a combination of your ideas. You can place the burlap on a flat surface, put the 703 down on the burlap, use about half a hand-print sized area at corners and middle of the long side, and stretch the burlap around to the glue area in back. If the adhesive you're using needs to be held in contact for a while, you can use boards with excercise weights or anything heavy to hold the burlap against the adhesive til it sets. Try to keep the weave of the burlap even at the first edge you glue, and then stretch the other side evenly according to weave lines as well - this will make the finished panels look more professional.
1" 703 seems a bit light for effective absorption, but it should help quite a bit if you space it from the wall - a 3" gap will cause it to absorb down to the same frequencies as 4", just not as MUCH absorption since the sound will have only 1/4 as far to travel through the fiberglas itself. For more absorption you could glue 2,3, or even 4 of the panels together before you wrapped them with the burlap.
If I'm correct in assuming that your room is rectangular except for the side-to-side slope of the ceiling, then modal distribution will be somewhat more important than if the room were set up as a Reflection-Free Zone - and, unfortunately, I just ran your dimensions in one of my spreadsheets and it's going to need some help.
Your average height of 9.5 feet is EXACTLY the same as the second harmonic of the length, so there are two different axes supporting several of the same frequencies. This can be really difficult, if not impossible, to correct for.
If it's not possible or practical to even out the ceiling by building it down to 9 feet all around, I would try mounting some of your 703 (spaced out 3") on sheets of plywood (1/2" should do) suspended (like clouds) over as much of the room as you can, (ESPECIALLY over the MIX area) hung level at either 8 or 9 feet (NOT 8.5, as that is half your 17 foot dimension) - The plywood will give you a "shell" effect, breaking up the modes that duplicate harmonics of the length, evening out the stereo field, and the 703 in front of the plywood will do what it always does, which is absorb early reflections off the ceiling.
The plywood can be suspended using eyebolts thru the plywood (before the 703 is applied) then those eye bolts can be hung from medium to heavy plant hooks in the ceiling, placed at the 4 corners and one in the center of each sheet of plywood. You can get HEAVY picture hanging wire, or LIGHT aircraft cable, at Home Depot for the long hangers, and go direct from plant hook to eyebolt on the shortest side (lowest part of the ceiling) Going direct from eyebolt to plant hook will require fairly careful measuring so they line up with each other.
As to LEDE plans, that kind of went out several years ago - it tended to make things too dead in the control room, plus you need a minimum of 12-15 feet behind your head before it's a good idea to leave the rear wall live. Otherwise, you get reflections off the back wall that are soon enough to cause phase cancellations/smearing in the stereo image.
Once you have the wall below the front window absorbed and the ceiling evened out, the next areas should be found with a mirror and a helper - basically, you move the mirror around held flat on all surfaces - anywhere you can see the speakers in the mirror from your mix position, you need absorption. These are the places I'd use multiple layers of the 1" 703, along with that front lower wall.
If you're using nearfields, depending on where you have them placed you also may get early reflections off your console surface, or even whatever shelves they are sitting on - use the mirror to check that as well; sometimes reflections off the console can't be helped, but other times people build their own desks and come up with ways around the console reflections - I'm working on plans for a mix desk that won't be level, but sloped slightly toward the front (once I finalize the rest of the details) to solve this.
See, and you thought YOU could ramble - I hope some of this was helpful... Steve
Soooo, when a Musician dies, do they hear the white noise at the end of the tunnel??!? Hmmmm...
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Ethan Winer
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Ethan Winer
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Folks,
Eric criticised my association of density to low frequency absorption in another forum and copied it here. But I responded there after he posted the copy here, so I'm copying my response here too. This issue is not as simple as Eric implies, as explained below. My point is not to start a fight or move that discussion here. Rather, anyone reading this thread should understand the limitations of the data Eric cited.
--Ethan
================
I believe the real issue is that the above data is incomplete. Further, I always recommend the FRK faced rigid fiberglass because its low frequency performance is far superior to unfaced fiberglass. Here is where the analysis becomes interesting.
If we consider the fiberglass as having linear absorption due to pure gasflow resistance, then the above table makes no sense. For example, why is two inches of 705 eight times more absorbent at 125 Hz than one inch? And why is two inches of 701 only a little better at 125 Hz than one inch? This shows me that more is going on than plain gasflow resistance. I believe that rigid fiberglass starts to behave like a diaphragm all by itself, especially as it is made denser. When you add a paper facing it becomes a true damped membrane, and performs even better at low frequencies.
More relevant to this discussion of material density is the limitation of the data itself. Since it is given only as full octaves, only very coarse trends can be seen. It would be much more revealing to see this data at 3rd or even 12th octaves. Even more important is the fact that the data stops abruptly at 125 Hz. I know for a fact that thick 705-FRK panels peak at a frequency much lower than 125 Hz.
Last year I had samples of 705-FRK tested at IBM's Hudson Valley Acoustics Lab (ASTM certified). When placed across a corner the absorption peaks at 100 Hz, then falls to nearly half at 125 Hz, and then rises to nearly as high at 160 Hz, then falls way down at 250 Hz, and comes back up at 400 Hz. All of this activity is completely hidden when viewed at full octaves! The dips at the standard octave frequencies make 705 appear much worse than it really is. They also hide the enormous absorption at 100 and 160 Hz, and completely hide what happens below 100 Hz. In that same test the absorption at 80 Hz was nearly as high as at 100 Hz, yet that too is ignored in the standard published data.
The only way to truly know if 6 pcf rigid fiberglass absorbs low frequencies more effectively than 3 pcf rigid fiberglass is to measure panels of both types at a finer resolution than the published octave specs. And measurements must also be taken at frequencies below 125 Hz. I am willing to pay the $400 testing fee myself if we can't resolve this by discussion, but here's more evidence that density is directly related to low frequency performance:
The following was faxed to me by Rock Wool Manufacturing company, Leeds, Alabama, USA for their Delta Mineral Wool boards. This data is for unfaced rigid mineral wool at 125 Hz, using panels that are two inches thick:
4 pcf 0.24
6 pcf 0.32
8 pcf 0.35
12 pcf 0.40
You can clearly see the linear improvement in absorption at 125 Hz as the material density is increased.
Eric criticised my association of density to low frequency absorption in another forum and copied it here. But I responded there after he posted the copy here, so I'm copying my response here too. This issue is not as simple as Eric implies, as explained below. My point is not to start a fight or move that discussion here. Rather, anyone reading this thread should understand the limitations of the data Eric cited.
--Ethan
================
I believe the real issue is that the above data is incomplete. Further, I always recommend the FRK faced rigid fiberglass because its low frequency performance is far superior to unfaced fiberglass. Here is where the analysis becomes interesting.
If we consider the fiberglass as having linear absorption due to pure gasflow resistance, then the above table makes no sense. For example, why is two inches of 705 eight times more absorbent at 125 Hz than one inch? And why is two inches of 701 only a little better at 125 Hz than one inch? This shows me that more is going on than plain gasflow resistance. I believe that rigid fiberglass starts to behave like a diaphragm all by itself, especially as it is made denser. When you add a paper facing it becomes a true damped membrane, and performs even better at low frequencies.
More relevant to this discussion of material density is the limitation of the data itself. Since it is given only as full octaves, only very coarse trends can be seen. It would be much more revealing to see this data at 3rd or even 12th octaves. Even more important is the fact that the data stops abruptly at 125 Hz. I know for a fact that thick 705-FRK panels peak at a frequency much lower than 125 Hz.
Last year I had samples of 705-FRK tested at IBM's Hudson Valley Acoustics Lab (ASTM certified). When placed across a corner the absorption peaks at 100 Hz, then falls to nearly half at 125 Hz, and then rises to nearly as high at 160 Hz, then falls way down at 250 Hz, and comes back up at 400 Hz. All of this activity is completely hidden when viewed at full octaves! The dips at the standard octave frequencies make 705 appear much worse than it really is. They also hide the enormous absorption at 100 and 160 Hz, and completely hide what happens below 100 Hz. In that same test the absorption at 80 Hz was nearly as high as at 100 Hz, yet that too is ignored in the standard published data.
The only way to truly know if 6 pcf rigid fiberglass absorbs low frequencies more effectively than 3 pcf rigid fiberglass is to measure panels of both types at a finer resolution than the published octave specs. And measurements must also be taken at frequencies below 125 Hz. I am willing to pay the $400 testing fee myself if we can't resolve this by discussion, but here's more evidence that density is directly related to low frequency performance:
The following was faxed to me by Rock Wool Manufacturing company, Leeds, Alabama, USA for their Delta Mineral Wool boards. This data is for unfaced rigid mineral wool at 125 Hz, using panels that are two inches thick:
4 pcf 0.24
6 pcf 0.32
8 pcf 0.35
12 pcf 0.40
You can clearly see the linear improvement in absorption at 125 Hz as the material density is increased.
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Charles Dayton
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- Location: Los Angeles
Firstly, I would like to thank you for taking the time to respond to my post. Secondly, I would like to apologize. The figures I gave for the studio dimentions were the incorrect memories of a late night posting. I've got a 10 month old boy who thinks 4 hours sleep is generous, so sometimes the numbers dance around a little. Here are the revised numbers; 7'5" high in the NW corner 8'5" in all the other corners. Front to back it is 17'7" long, with an equipment closet 3'7" x 3'5" in the SE corner. The south wall has two sofits for the HVAC, the lower is 2' high 16.5" deep, the top sofit is 2'3" from the ceiling down, and also 16.5" deep. So the room is 14'11" wide from the north wall to the south wall sofit, and 16'3.5" from the north wall to the south wall proper. The observation window is 3'9.5" up from the floor and is 6'3" x 2"9" centered on the west wall. where the mix position is. The rear wall or east wall has a couch with a 6' x6' shelving unit behind it. The whole room is double drywalled on staggered studs from the external structure (yes it was a garage!). The 3/4" plywood floor sits on 2 x 4s on edge, on neopreen pads on a concrete slab. The floor has carpet padding and carpet. Whew! O.K., how about angleing the 703 on the parallel walls? Do the sofits add to the amount of standing waves, because I now have two parallel surfaces on the north and south walls? Once again, thank you for your time. The math makes my head swim.
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Eric_Desart
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To Ethan,
You're a plague.
I stop responding to somebody who refuses to learn, and only reads sentences which fit in your goal.
And please stop doing if you know what you're talking about.
If you're learning, than don't act as THE ONE.
Only half a year ago I explained to you myself, how the 705 FRK worked, what the effect was of an airgap was behind absorption material.
You never saw a lab until ca half a year ago. You had hardly an idea how to interpret absorption data (easy to prove, all messages still on the net).
You hear a few words and build a story around it, as you pleases, even when you have no ore hardly an idea what you're writing. You're a reporter not an acoustician.
You make absolute statements and draw conclusions without any reasonable backing.
And the way you compare absorption values, in order to promote your products, are acoustically irresponsible, and as I said to you already, should be punishable by Belgian law.
I should like to forget about you and your site. The period I tried to explain things to you is over.
Only you don't let me. You invade the whole net.
You're site misuses the lack of knowledge in the studio world, but please don't act as an acoustician.
You only get your name as THE GURU by invading as you said yourself over 40 newsgroups, and writing as much as you can.
We really are from a different world.
Not understanding things is no problem. I have millions more questions than answers. But at least I don't play the GURU about subjects which aren't mine, and I question things, not give misleading info.
I leave space to you and leave this group, please feel further free to continue your nonsense and inaccurate and misleading site.
No best regards
Eric
Best regards to all others.
You're a plague.
I stop responding to somebody who refuses to learn, and only reads sentences which fit in your goal.
And please stop doing if you know what you're talking about.
If you're learning, than don't act as THE ONE.
Only half a year ago I explained to you myself, how the 705 FRK worked, what the effect was of an airgap was behind absorption material.
You never saw a lab until ca half a year ago. You had hardly an idea how to interpret absorption data (easy to prove, all messages still on the net).
You hear a few words and build a story around it, as you pleases, even when you have no ore hardly an idea what you're writing. You're a reporter not an acoustician.
You make absolute statements and draw conclusions without any reasonable backing.
And the way you compare absorption values, in order to promote your products, are acoustically irresponsible, and as I said to you already, should be punishable by Belgian law.
I should like to forget about you and your site. The period I tried to explain things to you is over.
Only you don't let me. You invade the whole net.
You're site misuses the lack of knowledge in the studio world, but please don't act as an acoustician.
You only get your name as THE GURU by invading as you said yourself over 40 newsgroups, and writing as much as you can.
We really are from a different world.
Not understanding things is no problem. I have millions more questions than answers. But at least I don't play the GURU about subjects which aren't mine, and I question things, not give misleading info.
I leave space to you and leave this group, please feel further free to continue your nonsense and inaccurate and misleading site.
No best regards
Eric
Best regards to all others.
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giles117
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yeah Eric stick around. Heck you rubbed me the wrong way, but I chose to be a bigger man and gain as much knowledge from you as possible. No Big deal. As you said to Ethan He needs to be a learner (I don't know, wasn't there)
But you have enlightened me in things that just seemed mathematically boring. I have asked you to simplify your information so I can understand it and you have.
I know most of us techinical people tend to talk static facts and never make it applicable to a real life situation for the listener to understand. If we do it is so verbose with technical jibber jabber they are lost.
I had to re-educate myself and learn how to explain electronics to people with no knowledge of the subjetc so that they could "get a clue."
So hang around bud. I will be picking that brain of yours more and more. Hopefully I can impart into you as well as time goes by.
Bryan Giles
But you have enlightened me in things that just seemed mathematically boring. I have asked you to simplify your information so I can understand it and you have.
I know most of us techinical people tend to talk static facts and never make it applicable to a real life situation for the listener to understand. If we do it is so verbose with technical jibber jabber they are lost.
I had to re-educate myself and learn how to explain electronics to people with no knowledge of the subjetc so that they could "get a clue."
So hang around bud. I will be picking that brain of yours more and more. Hopefully I can impart into you as well as time goes by.
Bryan Giles
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Ethan Winer
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Eric,
> Only half a year ago I explained to you myself, how the 705 FRK worked, what the effect was of an airgap was behind absorption material. <
That's not true. As I already explained elsewhere, I've understood 705 and air gaps since before 1978 when I built my first pro recording studio. My popular bass traps plans from 1995 Electronic Musician magazine show an air gap behind 703. You have indeed explained a lot to me over the past half-year, for which I am grateful, but please give me a little credit!
I really don't want to fight with you, and I don't enjoy seeing John's fine forum spoiled with negative words. You are doing that, not me. All I have done is discuss acoustic issues. I have never said one nasty word about you, yet you do that to me repeatedly.
Worse, you do exactly what you accuse me of: I already told you about my 1978 pro studio and 1995 article, yet you continue to repeat "I taught Ethan about 705 and air gaps" here and elsewhere. Then you say I'm irresponsible for misquoting data, yet that is exactly what you do with the absorption figures above. I believe that data is incomplete and misleading regarding density versus low frequency performance. If you disagree, then address my points and maybe we'll both learn something.
I have made many changes and additions to my Acoustics article on your good advice, and last week I went through my entire RealTraps site to remove text that could be perceived as unfair toward foam. I even offered to pay $400 of my own money to do a proper test of rigid fiberglass and density! What more do you want from me?
Let's discuss this without arguing - then everyone will benefit.
--Ethan
> Only half a year ago I explained to you myself, how the 705 FRK worked, what the effect was of an airgap was behind absorption material. <
That's not true. As I already explained elsewhere, I've understood 705 and air gaps since before 1978 when I built my first pro recording studio. My popular bass traps plans from 1995 Electronic Musician magazine show an air gap behind 703. You have indeed explained a lot to me over the past half-year, for which I am grateful, but please give me a little credit!
I really don't want to fight with you, and I don't enjoy seeing John's fine forum spoiled with negative words. You are doing that, not me. All I have done is discuss acoustic issues. I have never said one nasty word about you, yet you do that to me repeatedly.
Worse, you do exactly what you accuse me of: I already told you about my 1978 pro studio and 1995 article, yet you continue to repeat "I taught Ethan about 705 and air gaps" here and elsewhere. Then you say I'm irresponsible for misquoting data, yet that is exactly what you do with the absorption figures above. I believe that data is incomplete and misleading regarding density versus low frequency performance. If you disagree, then address my points and maybe we'll both learn something.
I have made many changes and additions to my Acoustics article on your good advice, and last week I went through my entire RealTraps site to remove text that could be perceived as unfair toward foam. I even offered to pay $400 of my own money to do a proper test of rigid fiberglass and density! What more do you want from me?
Let's discuss this without arguing - then everyone will benefit.
--Ethan
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Johannes
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- Contact:
Eric, don't leave!
Eric don't leave!
Your threat of leaving even makes a lurker post!!!
Your knowledge is very well appreciated!
Don't take it too personal, the only way to make your point to keep posting.
Your threat of leaving even makes a lurker post!!!
Your knowledge is very well appreciated!
Don't take it too personal, the only way to make your point to keep posting.
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AndrewMc
- Posts: 178
- Joined: Tue Apr 22, 2003 8:55 am
- Location: New Orleans, USA
Eric - here's very much hoping that you stay 
You have a wonderful depth of knowledge & I hope to continue to learn much from your posts. I know it's unfortuanate that people like myself who are just learning have nothing to give back in return except appreciation.
Your involvement here is VERY much appreciated.
You have a wonderful depth of knowledge & I hope to continue to learn much from your posts. I know it's unfortuanate that people like myself who are just learning have nothing to give back in return except appreciation.
Your involvement here is VERY much appreciated.
Andrew McMaster