Do paint and carpets affect the sound?

[Soandso]

They modulated the intensity of a red laser with a 1 kHz sine wave from a signal generator, shone it through a layer of paint onto a photodetector, the output of which was somehow driving a speaker. By measuring the sound output of the speaker, they obtained some manner of indication of the transmissivity of the different paints. It's a ridiculous experimental setup, and if they were my students, they'd be getting a failing grade.

@masr, - You have belatedly acknowledged it was not light, as previously asserted, but was sound "... transmissivity of the different paints...." they were "measuring." And yet, for some reason, refrain from concisely stating that the "...manner of indication ..." was in dB.

I don't see why students would merit a failing grade if they generate reproducible data showing the relative pattern of sound transmissivity through colors is demonstrably similar even when alter matched levels of the pigment. Criticizing it as a "...ridiculous experimental setup..." is easy to expound, yet I am still awaiting remotely similar research being presented on this thread.

 

[Soandso]

Wait… Are you an author of the paper?

Forum tip: if you prefix an “@“ to another members ID, they will get notified of mention, and it’s easier to pick out of the text. @Soandso, for example

dc655321, - No, I am not an author of the paper. I posted my synthesis of a specific methodology quote because more than one commentator insisted the cited research was about light. Although challenged if I read the report it seemed to me there was, in some, a reading comprehension issue that it was definitely about sound.

I'll try your @ strategy soon, thanx.

 

[mansr]

You have belatedly acknowledged

I have done no such thing.

it was not light, as previously asserted, but was sound "... transmissivity of the different paints...." they were "measuring." And yet, for some reason, refrain from concisely stating that the "...manner of indication ..." was in dB.

Where in the experimental setup did, in your interpretation, sound waves interact with the paint?

 

[dc655321]

dc655321, - No, I am not an author of the paper. I posted my synthesis of a specific methodology quote because more than one commentator insisted the cited research was about light. Although challenged if I read the report it seemed to me there was, in some, a reading comprehension issue that it was definitely about sound.

I'll try your @ strategy soon, thanx.

I don’t think there is reading comprehension issue - NTK and Mans are as sharp as they come.

 

[fuzzychaos]

Hmmmm, I have Buchardt A500’s and a wireless hub. What kind of cable risers should I use?

 

[Soandso]

I don’t think there is reading comprehension issue - NTK and Mans are as sharp as they come.

dc655321, - Then why were "sharp" commentators not able to understand the cited paper was not about light, but clearly stated about sound transmission loss? ASR is about learning and the fun of doing so - not misleading other people.

 

[dc655321]

dc655321, - Then why were "sharp" commentators not able to understand the cited paper was not about light, but clearly stated a out sound transmission loss? ASR is about learning and the fun of doing so - not misleading other people.

The losses are from the acoustic signal riding riding on the optical wave, it’s true. But it’s the optical signal that is being attenuated, along with it’s modulated envelope.

How could you possibly conclude otherwise?

 

[mansr]

The losses are from the acoustic signal riding riding on the optical wave, it’s true. But it’s the optical signal that is being attenuated, along with it’s modulated envelope.

How could you possibly conclude otherwise?

Maybe if you printed the paper, rolled it up, and smoked it...

 

[Soandso]

The losses are from the acoustic signal riding riding on the optical wave, it’s true. But it’s the optical signal that is being attenuated, along with it’s modulated envelope.

How could you possibly conclude otherwise?

dc655321, - The researchers state they go on to separate sound signal and measure that in dB. They did not report making any measurements of the optical wave once separate.

The author's describe amplitude modulation "... as the change of the intensity of the laser beam with sound ...." If you are prepared to state the attenuated optical wave, by some specific dynamic, in turn significantly modulates how sound passes through color then explain that.

Such laser equipment for carrying acoustic signals is apparently an established part of certain scientific manipulations and reliably significant enough for different designs to be manufactured. Hence there should be published literature if the actively "... modulated envelope ..." attenuated the sound signal to any degree, and known limitations of usage relevant to measurable aspects of sound signals.

 

[Soandso]

They modulated the intensity of a red laser with a 1 kHz sine wave from a signal generator, shone it through a layer of paint onto a photodetector, the output of which was somehow driving a speaker. By measuring the sound output of the speaker, they obtained some manner of indication of the transmissivity of the different paints. It's a ridiculous experimental setup, and if they were my students, they'd be getting a failing grade.

mansr, - Someone asked the question: "... how the laser would help ...." Challenged to elaborate an erudite explanation you offered no new insight and managed to state some mis-information.

Red was not the color of the laser light, but rather one of the tested colors which the laser carried sound passed through. Inquiring minds want to know if you already smoked a rolled up paper copy of the report when you tried to pass that off.

 

[tmtomh]

@masr, - You have belatedly acknowledged it was not light, as previously asserted, but was sound "... transmissivity of the different paints...." they were "measuring." And yet, for some reason, refrain from concisely stating that the "...manner of indication ..." was in dB.

I don't see why students would merit a failing grade if they generate reproducible data showing the relative pattern of sound transmissivity through colors is demonstrably similar even when alter matched levels of the pigment. Criticizing it as a "...ridiculous experimental setup..." is easy to expound, yet I am still awaiting remotely similar research being presented on this thread

The manner of indication was sound - but the transmissivity being measured was of light, not sound.

 

[dc655321]

Red was not the color of the laser light,

674.6 nm is way red.
It might be a good idea to think about what else you might not be grasping.

 

[Soandso]

The manner of indication was sound - but the transmissivity being measured was of light, not sound.

tmtomh, - If it was solely due to inherent properties of the laser's interaction with specific colors that prevented some proportion of the dB of 1,000 Hz sound carried by that laser from going through the different color does this prove by removing the laser for use that all colors of paint of the same pigment density are equally penetrable by the same dB of audible sound?

And supposing that is the case (absence of any laser) then is it 100% of dB, or what lesser % of dB, which passes through all colors of paint for the same given sound frequency?

 

[Soandso]

674.6 nm is way red.
It might be a good idea to think about what else you might not be grasping.

dc655321, - Thank you for correcting me on that.

 

[DanielT]

dc655321, - Figure 2 of cited report shows they investigated 82dB[A] of 1,000 Hz
sound transmission fine focus carried by a laser through different colors. The "photo-detector" was NOT a color additive/subtractive illumination filter but to isolate precisely which color they were testing.

And their data was what was picked up how much sound made it through a specific color that engaged a speaker, which in turn produced dB[A] readings specific to each tested color (and various concentrations of each color pigment).

Those are details more precisely in the report section "Materials and Methods.

Since the same test 82dB sound passed through different colors and after being transmitted through those different colors had different measurable dB the implication is that different colors let sound through to different degrees. I posit that some of that difference in end point dB levels indicates different amounts of sound dB reflection (&/or scattering) for different colors.

I do see that I mistakenly inverted the "sound transmission loss" for the colors; my mistake multi-tasking and I apologize for any misleading. For specific data see Fig. 1 first column about "STL" (sound transmission loss) per dB for several color experiments. And to quote their "Conclusions" section: "Sound transmission loss changes with colour of the surface as follows; in green 6.6dB[A], ... red 5.6dB[A], and yellow 4.6dB[A]."

You may have mentioned it in the thread, in which case I have missed it if not:
*The next step in science. Has this study, you are referring to, been replicated by other researchers? Have they got the same result?
*Has the study been published in any recognized scientific journal and commented on?

Edit:
I have to say that you really spice up the thread and made it much more interesting than I thought it would be.

 

[Soandso]

Hmmmm, I have Buchardt A500’s and a wireless hub. What kind of cable risers should I use?

red

You may have mentioned it in the thread, in which case I have missed it if not:

The next step in science. Has this study, you are referring to, been replicated by other researchers? Have they got the same result?

Has the study been published in any recognized scientific journal and commented on?

Edit:
I have to say that you really spice up the thread and made it much more interesting than I thought it would be.

DanielT, - That study was from 2020 and I have not seen anything similar.

 

[Soandso]

674.6 nm is way red.
It might be a good idea to think about what else you might not be grasping.

dc655321, - The report does state the "... wavelength of the modified laser color is the most important parameter of the reflective percentage...." There are additional parameters of a color's surface tension energy and pigment concentration.

Are you willing to assert that in the absence of the laser all different colors permit the same db of 1 kHz sound through them if their pigment percentage is matched?

 

[mansr]

You may have mentioned it in the thread, in which case I have missed it if not:
*The next step in science. Has this study, you are referring to, been replicated by other researchers? Have they got the same result?

I'd like to think that this level of incompetence is rare enough that nobody else has made the same series of mistakes.

Maybe they read something like this and misunderstood it completely: https://www.sciencedirect.com/science/article/pii/S0041624X19300666

*Has the study been published in any recognized scientific journal and commented on?

I sure hope not.

 

[DanielT]

I'd like to think that this level of incompetence is rare enough that nobody else has made the same series of mistakes.

Maybe they read something like this and misunderstood it completely: https://www.sciencedirect.com/science/article/pii/S0041624X19300666


I sure hope not.

The report Soandso refers to.Strange that such a "scientific" report is published. If it is professional researchers who publish the results?

That report should be read by colleagues before publishing, given what you are writing.I think it seems to be a reasonable process, a check among colleagues, although I am not a researcher in the natural sciences.

Edit:
Good tip, your link. A little too advanced for me but others can probably find it interesting.

 

[Astoneroad]

Hmmmm, I have Buchardt A500’s and a wireless hub. What kind of cable risers should I use?

Purple.