Archive for category Q&A

Phones and Scones? I mean… Phons and Sones!

如果nce it’s been a while, I have received approval to write about phones and scones – yummy! Oh, I misread that… I can talk about phons and sones? Oh boy. I mean… hmm… uh…

Every so often, you get exposed to a term that you’ve never heard; it seems like someone just made it up – and the more you learn about it, the more made up it seems.
(Disclaimer: I swear I didn’t make these up.)
Today, I will introduce you to two of these amazingly real terms, and do my best to explain why these terms exist… prepare to be amazed!

好的。方在心理和索恩斯是两个相关的术语o-acoustics that refer to how humans perceive the “LOUDNESS” of sounds. These are actual real concepts. (Stop laughing.)

Don’t we all perceive sound differently? YES!

So how can you have an actual measurement based on something that everyone perceives differently? EASY!

Take a bunch of people.
Play a 1Khz sine wave.
Play another frequency.
Ask them if it sounds just as loud.
Repeat. (No kidding.)

OK, this is over simplified… Let’s start by setting some rules that make this a little easier.

For reference – whatever dB level that 1KHz wave is will be the reference for the whole group… compare a bunch of frequencies at different levels to 1Khz at 40 dB – and we’ll call all the ones that sound just as loud the “40 PHON Equal Loudness contour.”

Why? Because they sound just as loud as the 1kHz wave at 40 dB. (I’m not joking!)

Then compare a bunch to a 1KHz wave at 50dB and call all of those that sound as loud, (wait for it)
the “50 PHON Equal Loudness contour.”

Then 60dB, 70dB, 80dB… etc (see a pattern?)
Now, plot all of these from a bunch of people who hear pretty well… take an average and WHAMMO!!!

The PHON Equal Loudness contours!

Equal Loudness Contours.

ISO 226:2003 Equal Loudness Contours.

(To be fair this is the data from a bunch of 18-25 year olds who still have reasonably good hearing…)

Remember this is PERCEIVED LOUDNESS. The average of what the test subjects said “yeah, uh, that’s just as loud, Dude.”

似乎奇怪不是吗——这些不是倪ce straight lines? That’s because the human ear is constructed in such a way to be more sensitive to certain frequencies than others.

So according to this chart – a 1KHz wave at 40 dB sounds just as loud as 125 Hz at ~60dB and 3150 Hz at ~35 dB. (All on the 40 Phon contour.)

That’s Psycho-acoustics for you. (Wow.)
So if you’re an average person with average hearing, your bass perception is terrible and over 16KHz you’re basically – well… deaf.
But you hear really well from 2kHz – 5kHz!

Anyway… what’s the point?

Phons measure how loud the human ear perceives sounds at different frequencies. (TADA!)

FINE! – then what are Sones ? To make this simple – Sones are relabeled Phons.
You start with 40 Phon being 1 Sone then double it every 10 Phon.

40 Phon = 1 Sone.
50 Phon = 2 Sones.
60 Phon = 4 Sones.
70 Phon = 8 Sones.
80 Phon = 16 Sones
90 Phon = 32 Sones
100 Phon = 64 Sones
Etc.

(Hmm, thought that would be more complicated? It is – but that’s basically it in a nutshell.)

You will almost never see a phon or a sone. Bathroom exhaust fans and blowers are sometimes rated in Sones – to let you know how quiet they are… The problem is that no one actually knew how quiet that was until now!

I guess it sounds better to say –

2.5 Sones! Wow that's Quiet!

Quiet… Only 2.5 Sones!

“This bathroom fan operates at only 2.5 Sones!”

…Than it would be to say…

Quietish... Only loudish in frequencies you can't hear well. So it's not bad... Really.

Quietish… Only loudish in frequencies you can’t hear well. So it’s not bad… Really.

“This bathroom fan resonates at over 80dB,
but it’s in a frequency range that humans don’t hear very well,
so it sounds quieter than it actually is… no… really!”

Human perception of sound is very important to the development of acoustic products – Psycho-acoustics are not a joke.
(Why are you still laughing?)

,,,,

Leave a comment

Blocking Piano Sound from an Adjoining Classroom

QUESTION:

We have a piano class next to a classroom and the sound loves to leak through our thin walls. We need a type of sound proofing wall the teacher can still staple pictures and information to and block out all sound going through her wall bugging the other class. The wall is about 24′ x 12′. What can you suggest?

ANSWER:

Installing a layer of theBlockAid Sound Barrieron top of the existing shared wall will block the transmission of sound through the wall. Be sure to examine to overall construction of the room. If a suspended ceiling grid is in use, sound could possibly flank over the wall if it does not go all the way to the roof deck. Blocking sound requires that massive and dense structures be in place to interrupt the path of the sound or noise. Be sure to seal any seams or gaps as well as any wall switches or boxes. If air can pass through an area of the wall, so can sound.

More on vinyl sound barrier: http://www.acousticsfirst.com/blockaid-vinyl-sound-barrier.htm

Once the barrier is installed, a finish material will need to be installed over this. We would recommend 1/2″ wall board or something simple like theSound Channels Acoustical Wall fabric. Sound Channels in installed in a similar manner to wall carpet and is Velcro compatible. It also is a Class A material that passes vertical and corner burn tests.

We can also custom manufacture 2″ thickSonora Acoustical Wall Panelswith a barrier septum in the middle and a Tackable Face. This will combine sound absorption along with thesound barrierand add a fabric finish, all in one step. We would recommend doing this in two sections of 4′(w) x 6′(h) panels.

As always, be sure to discuss your project with an acoustical consultant or experienced professional to determine which materials best suit your application, site constraints and budget.

——————————————————————————————————————————————-

Acoustics First Corporation supplies acoustical panels and soundproofing materials to control sound and eliminate noise in commercial, residential, government, and institutional applications worldwide. Products include the patented Art Diffusor®, sound absorbers, noise barriers, acoustical fabrics and accessories. Acoustics First® products are sold for O.E.M applications, direct, and through dealers. For more information on acoustical materials and their application, please visitwww.AcousticsFirst.comor callToll Free 1-888-765-2900(US & Canada).

,,,,,,,

Leave a comment

Acoustical Material Design and Uses Q&A

Below is a Q&A session about acoustical materials.

How would you describe the existing landscape relating to acoustical systems? Where is the greatest need/ the most demand?
-Acoustical systems are deployed throughout many market segments. Demand truly depends upon the specific type of acoustical requirement. Applications can range from improving sound in a residential home theater to solutions to abate jet airplane noise. Many of these projects must be examined on a case by case basis.

Popular Products
Fabric wrapped panel:http://www.acousticsfirst.com/sonora-wall-panels.htm
Sound Barrier:http://www.acousticsfirst.com/blockaid-vinyl-sound-barrier.htm
Art Diffusors:http://www.acousticsfirst.com/diffuser-art-diffusor.htm

What are some major issues that come up or problems to be faced?
-Most problems center around improving speech intelligibility or keeping sound from disturbing others.
Improve Intelligibility withAbsorbers:http://www.acousticsfirst.com/sound-absorbers.htm
Block Sound withBarriers and Isolation Poducts:http://www.acousticsfirst.com/barriers-vibration-isolation.htm

When developing different types of sound proofing/ sound dampening materials what have proved to be the most useful materials to form composites out of? Where do you usually procure these base materials?

许多吸收器产品的人ufactured from fluffy or porous materials such asacoustical foamandglass fiber.
Noise barriersare made from dense and heavy materials andisolation materialsrange from metal springs to neoprene rubber.

You can read more about the basic categories of products here:http://www.acousticsfirst.com/acoustics-first-products-overview.htm

Which materials or composites combinations have proved to be the most successful?
-The success of the material can only be measured in comparison with the application in which the material is used. Not all applications will require the absolute best composite material. There are varying degrees of requirements and materials that should be specified by a professional who can evaluate the project requirements. Acoustical consultants are often used to determine the appropriate material and amounts of material for the specific project.

What surprises have you encountered while developing acoustical systems?
-Sometimes that physical limitations of materials or structures to support the materials may change the design or specification of an acoustic material. For example, when blocking sound, massive and dense materials should be used, however, you must be sure the structure will be able to support the additional weight. A prototype design may have the best intentions of being a great acoustical material but may have limitations when manufacturing, shipping or installing.

How big is the market for aesthetically pleasing sound proofing/ dampening systems?
-These days most markets segments are looking for materials that are aesthetically pleasing while at the same time needing them to be economical. Visual trends are constantly changing and consumers may choose to compromise the look of a material to match their project’s budget.

Do you see any future trends? Where do they align?
-Trends are always changing based on market demand whereas material design and availability change based on the availability of access to raw goods at a fair price. One constant that could maintain is that as the population grows one can anticipate the need for noise and sound control materials will also increase.

Do you think there is a need or interest in easily movable/ modifiable/ adjustable sound proofing/ dampening?
-Many customers would like to have the ability to remove or move their acoustical materials. Much of this depends on the type of acoustical problem and how the will be installed.

Do you think there is a need or interest in sound proofing/ dampening that is easily cleaned? In what market do you think these exist?
-Some commercial applications such as hospitals, food service, or industrial facilities need materials that can be wiped down. This depends on the environment in which the materials will be used.

What are some markets that have unmet needs? What is the need?
-Any markets that have sound and noise problems.

——————————————————————————————————————————————-

Acoustics First Corporation supplies acoustical panels and soundproofing materials to control sound and eliminate noise in commercial, residential, government, and institutional applications worldwide. Products include the patented Art Diffusor®, sound absorbers, noise barriers, acoustical fabrics and accessories. Acoustics First® products are sold for O.E.M applications, direct, and through dealers. For more information on acoustical materials and their application, please visitwww.AcousticsFirst.comor callToll Free 1-888-765-2900(US & Canada).

,,,,,,,,,,

Leave a comment

Baidu
map