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crouser67
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most effective corner treatment for $0

I needed to control hi-freq noise from the ceiling corners. I affixed 1 ft. square cardboard type egg trays with pushpins - two trays per front corner on the walls and one in each rear corner (rear wall). I only had six trays and I have a drop ceiling with a somewhat textured surface, so I felt I could forego placing them on the ceiling. The effect was well beyond my expectations. Photo is posted in DIY Projects gallery.

Kal Rubinson
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Re: most effective corner treatment for $0


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I needed to control hi-freq noise from the ceiling corners. I affixed 1 ft. square cardboard type egg trays with pushpins - two trays per front corner on the walls and one in each rear corner (rear wall). I only had six trays and I have a drop ceiling with a somewhat textured surface, so I felt I could forego placing them on the ceiling. The effect was well beyond my expectations.

Not surprising. My expectations for the effectiveness of this would not be very high.

Kal

KBK
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Re: most effective corner treatment for $0

Enid Lumley used to hang wet towels in her listening space/room. Low humidity to high humidity will change acoustics by 10db in the highs. Not so crazy.

Hanging wet towels. Hhmmm.. Lets look at pro room correction for film sets, and professional/commercial/industrial applications..or correction.

Elk
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Re: most effective corner treatment for $0

Why would high humidity be beneficial?

Humid air is less dense than dry air and conducts sound less effectively.

KBK
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Re: most effective corner treatment for $0

There is a wave-particle transition at a certain frequency that is oddly enough, quite similar to skin effect considerations that occur with electrical audio signals and wire. I mean like, go figure. I know that's not the exact answer or direction you were talking about, but..it's part of it.

When you take the differential between the two humidity considerations and add in into it that the human factor, then the whole thing shows it self to be a major boner in the review process that needs be addressed.

Depending on their physical review location, reviewers need to have humidity added to their listening-evaluation rooms in the winter, and removed in the summer.

Otherwise, their evaluations stand a good chance of being invalid, or a least not the same as the 'ear' of the person who made the speaker, with regards to actual base reference points.

This leads to a standard needing to be enacted for reviewers, manufacturers and the sellers of high end gear.

The larger players of selling such gear tend to skip into a standardized environment, to some degree,sheerly due to location and size of establishment.

Sound by Singer, due to the store size, makes one guess that they can and largely do have a standardized environment. Not due to the attempt and knowledge applied directly, I'm guessing, but sheerly due to the environmental gear utilized in such a large location. So do others, is my guess-due to their size of establishment.

Such re-selling locations would tout a point in their promotional literature and public stance, if they were aware of such critical consideration-and I have not seen it, so the situation is happenstance at best.

Bigger studios that are shall we way, a bit more 'self aware', do tend to have humidifiers and de-humidifiers for their various reasons. Mostly to maintain the physical condition of wood instruments and the like, but some recognize them as part of their 'secret weapon' package that they don't really speak about, when it comes to fine tuning the auditory presentation.

Where I'm at, the humidity changes from 10-15% in the winter...to 90% in the summer.

The audio systems go from "suck-ass thin" in the winter..to "properly balanced and rockin" in the summer. Dry air also equates to capacitance build up on cables. No drain. High dielectric considerations. Slippers on carpet, huge shocks, etc. These things show themselves to play out as being quite huge - with regards to being cumulative effects.

If stereophile wants to do a first and be a 'leader in the world of audio', then they'd do well to consider playing with this phenomena, and then understanding the effect --and then the efficacy of enacting a 'standard' for their reviewers.

High end is all about minute differences being considered..therefore something such as this which can play a part, needs be looked at in a serious way.

Elk
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Re: most effective corner treatment for $0


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This leads to a standard needing to be enacted for reviewers, manufacturers and the sellers of high end gear.


This I can accept in principle - not that humid is better than dry, just that sound transmission is different depending on humidity.

Buddha
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Re: most effective corner treatment for $0

When we demo'd our first year at T.H.E. we used wine shipping containers as corner treatments. They looked kind of cool, and the tops were different from the bottoms, so we had some play options.

We actually had a few people ask about specs and retail price points!

We were actually quite pleased with the results!

Nothing better than "found" audio tweaks!

KBK
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Re: most effective corner treatment for $0

There's no reason why you wouldn't be pleased with the results. 100% correct in form and function?, -I'm sure you didn't think so. But definitely doing something, likely something better than a bare corner. This would be more noticeable with the planar drive systems that you had in the room. I'd argue that they'd likely be perceived as less of a benefit with dynamic driver speakers, even though some change or benefit might be realized.

KBK
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Re: most effective corner treatment for $0


Quote:

Quote:
This leads to a standard needing to be enacted for reviewers, manufacturers and the sellers of high end gear.


This I can accept in principle - not that humid is better than dry, just that sound transmission is different depending on humidity.

I agree, I use minimal air conditioning in the summer and it keeps the humidity around the 50% mark.

piinob
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Re: most effective corner treatment for $0

Actually, humidity adds density. For a given volume of space the moister air will be denser. Water also conducts sound better than air so it would seem to make sense that moist air would help sound transmission, especially the higher frequencys. Colder air is also denser so temperature should play a part in this also. KBK is right in that someone, maybe JA and Co., or someone else should look into this. Or maybe some accoustic PHD already has and we have not found it yet.

mrlowry
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Re: most effective corner treatment for $0

Buddha-

. . .and you get to drink the wine too! Very clever. If you were to commercially market this tweak it would make your wine habit turn a profit.

KBK

I've been thinking about the humidity affecting the sound of my CLS speakers for a while. I'm glad that I'm not nuts, well not about that anyway.

Buddha
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Re: most effective corner treatment for $0


Quote:
Actually, humidity adds density. For a given volume of space the moister air will be denser. Water also conducts sound better than air so it would seem to make sense that moist air would help sound transmission, especially the higher frequencys. Colder air is also denser so temperature should play a part in this also. KBK is right in that someone, maybe JA and Co., or someone else should look into this. Or maybe some accoustic PHD already has and we have not found it yet.

Then why do clouds float?

Adding water vapor to air actually makes it less dense.

Otherwise, I'm on board - saving up for that dedicated listening room at the lowest point of Death Valley - dense and dry air...maybe that 2A3 single ended triode really could drive my speakers!

Of course, that 2A3 may lower the density of my room's air what with the warmth it gives off.

Sometimes a guy can't win.

piinob
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Re: most effective corner treatment for $0

Clouds float because of differential temperature. As it heats it will expand and rise, but that doesn't mean that the water/air mix is less dense than the air alone for the same temperature. We introduce humidity into the air going into Combustion Turbines because internal combustion engines have an equation that says more mass flow equals more power and greater efficiency. It works.

rabpaul
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Re: most effective corner treatment for $0


Quote:

Quote:
Actually, humidity adds density. For a given volume of space the moister air will be denser. Water also conducts sound better than air so it would seem to make sense that moist air would help sound transmission, especially the higher frequencys. Colder air is also denser so temperature should play a part in this also. KBK is right in that someone, maybe JA and Co., or someone else should look into this. Or maybe some accoustic PHD already has and we have not found it yet.

Then why do clouds float?

Adding water vapor to air actually makes it less dense.


Density=Mass/Volume e.g 1 cc of water weighs 1 gram hence water has a density of 1.
At low temperatures and/or high altitudes, clouds form as a result of a large collection of tiny droplets of water or ice crystals. The droplets are so small and light that they can float in the air.
In theory higher the density the faster the speed of sound the caveat being the temperature is the same. With air being the medium although cold air is denser, sound travels faster in hot air.

Buddha
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Re: most effective corner treatment for $0

To see why humid air is less dense than dry air, we need to turn to one of the laws of nature the Italian physicist Amadeo Avogadro discovered in the early 1800s, which you might recall from your high school chemistry class.

In simple terms, Avogadro found that a fixed volume of gas, say one cubic meter, at the same temperature and pressure, would always have the same number of molecules no matter what gas is in the container. Most beginning chemistry books explain how this works.

Imagine a cubic foot of perfectly dry air. It contains about 78% nitrogen molecules, which each have an atomic weight of 28. Another 21% of the air is oxygen, with each molecule having an atomic weight of 32. The final one percent is a mixture of other gases, which we won't worry about.

Molecules are free to move in and out of our cubic foot of air. What Avogadro discovered leads us to conclude that if we added water vapor molecules to our cubic foot of air, some of the nitrogen and oxygen molecules would leave

KBK
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Re: most effective corner treatment for $0

I've owned CLS's before, and long enough to go through a full seasonal cycle with them.

The CLS deals with multiple issues, as does any electrostat.

You've got dielectric charge/change situations due to humidity, and the mylar taking on moisture loosening the panels(adding mass as well) and then the air density and humidity changes themselves creating it's own basic response change issues, via actual 'in air' and 'surface coupling' considerations. The true electrostat panel, being closest of all of any driver type, with respects to driver mass equaling air mass, has a fabulous accuracy of it's own due to the 'mass- coupling' effect, but this has dark side of being more affected by air changes, for the reasons stated. Can't have it all.

The three together can and do alter the sound of the elctrostats as a notable cumulative effect. ML's do best in stable controlled environments.

Planars like the maggies and the Apogees still show the effect to some degree..the Apogees least of all of the planar class, being a true metal ribbon of notably higher mass.

Maggies sit in the middle of the effect/affected range, due to the panel design. The true electrostats like the ML's tend to be the most affected.

I'll say I like all three types and have owned all three types before. I liked them all. All have their strengths and those are noted and enjoyed by the owners of said panels.

Buddha
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Re: most effective corner treatment for $0

"With air being the medium although cold air is denser, sound travels faster in hot air."

That must be why I feel I need to sit closer to the speakers when it's cooler.

Thanks! I did not know that about the speed of sound!

Buddha
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Re: most effective corner treatment for $0


Quote:
I've owned CLS's before, and long enough to go through a full seasonal cycle with them.

The CLS deals with multiple issues, as does any electrostat.

You've got dielectric charge/change situations due to humidity, and the mylar taking on moisture loosening the panels(adding mass as well) and then the air density and humidity changes themselves creating it's own basic response change issues, via actual 'in air' and 'surface coupling' considerations. The true electrostat panel, being closest of all of any driver type, with respects to driver mass equaling air mass, has a fabulous accuracy of it's own due to the 'mass- coupling' effect, but this has dark side of being more affected by air changes, for the reasons stated. Can't have it all.

The three together can and do alter the sound of the elctrostats as a notable cumulative effect. ML's do best in stable controlled environments.

Planars like the maggies and the Apogees still show the effect to some degree..the Apogees least of all of the planar class, being a true metal ribbon of notably higher mass.

Maggies sit in the middle of the effect/affected range, due to the panel design. The true electrostats like the ML's tend to be the most affected.

I'll say I like all three types and have owned all three types before. I liked them all. All have their strengths and those are noted and enjoyed by the owners of said panels.

I think maybe I have found that electrostatics are also the most altitude sensitive.

I bet JA can recall some experiences from Santa Fe with regard to Hi Fi performance.

mrlowry
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Re: most effective corner treatment for $0

I've often been mystified by how much the performances of CLSs can change from one day to another. I have always noticed that it seemed to be when there were massive shifts in weather conditions. In the winter I run a humidifier for my allergies which seems to improve the sound to. KBK, Any idea what the ideal conditions would be?

piinob
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Re: most effective corner treatment for $0

I stand corrected. Thank you.

Elk
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Re: most effective corner treatment for $0


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Actually, humidity adds density.


No. We think this as humidity feels "heavy" to us as our bodies do not cool or heat as well when air is moist.

A water molecule weighs only 0.622 as much as the mean of dry air molecules. Very moist air is quite a bit less dense than dry air at the same temperature and pressure.

These calculations are important when flying a plane so I know them quite well.)

KBK
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Re: most effective corner treatment for $0


Quote:
I've often been mystified by how much the performances of CLSs can change from one day to another. I have always noticed that it seemed to be when there were massive shifts in weather conditions. In the winter I run a humidifier for my allergies which seems to improve the sound to. KBK, Any idea what the ideal conditions would be?

I've no idea, really. I would simply do my best to have a stable environment so as to be able to have a 'place to stand' when tweaking. Then improve from there. Just another variable to pile on!

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