10 * bLog (p²)

Architects and Sound - Part the Third

2008-05-14T15:25:00.009-05:00

Continuing on a previous theme, here's another little piece from ProAV that is delving into the "us vs. them" of acousticians and architects.

We've been seeing quite a bit of this recently. Perhaps we'll all start to get along with each other in the near future? 8^D

Obsolescence in Acoustics

2008-04-16T11:43:00.004-05:00

Read about this site in today's paper. Got me to thinking about skills in my profession that are now becoming, or have become, obsolete. Among them:

Using sound level meters with analog (needle) displays (though Radio Shack still sells one).
Using special protractors and level recorder chart strips to determine reverberation time from impulse response recordings.
Using a starter's pistol, a large balloon, or two 2x4s to generate the aforementioned impulse responses.
Printing drawings on vellum to create bona fide blue blueprints. (I do miss the smell of ammonia around the office...)
Changing pens in a pen plotter.
Editing reel-to-reel tapes with a razor blade and some Scotch tape.
Attaching filter sets to sound level meters to measure octave-band sound levels.
Writing acoustical "modeling" and analysis programs in BASIC or Fortran.
Amassing hard copies of JASA.
Measuring relative humidity with a sling psychrometer.

I'm sure I'll think of more! 8^D

Local Bookstore Plug - The Book Bank

2008-04-11T11:45:00.007-05:00

When I travel - for business or pleasure - I try to find "the local bookstore." I'm not talking about the Borders or B&Ns. Not even the "half price" chains. I'm talking about the little hole-in-the-wall places that have books stacked to the ceiling; boxes of books that in any other store would be tripping hazards; books stacked two or three deep on a shelf.

I'm talking about the bookstores where the proprietors are behind the counter reading Faulkner or Joyce while their 17-year-old tabby sits on a stool in the Biography section.

I'm talking about the bookstores where, when you approach the counter with a rare (but not valuable) paperback copy of Asimov's The Gods Themselves priced at $1.50, the same proprietor compliments you on a fantastic find.

These bookstores have a personality. The smell of old paper. The coziness of 14-inch wide aisles. The low hum of traffic outside the only reminder that you haven't died and gone to book nerd heaven.

My latest find was on a recent trip out east. If you're ever in Alexandria, Virginia, I recommend you look up the Book Bank on King Street (just down the street from the national headquarters of the NSPE). Great selection of titles and wonderful prices. Not to mention the "local bookstore" atmosphere that is becoming increasingly difficult to track down in the Information Age.

Happy reading... 8^D

Happy April 1

2008-04-01T17:38:00.002-05:00

My favorite has to be #7.

If anyone has any good audio or acoustics related April Fool's Day pranks, let me know!!!

Just in time for Easter, Studiotips rises...

2008-03-20T18:32:00.003-05:00

Fortunately - this time - a misunderstanding. Disaster averted. Savant is glad to have his e-home back. And very relieved... 8^D

Happy Birthday, Pa Bell!

2008-03-03T12:48:00.002-06:00

Alexander Graham Bell, b. March 3, 1847.

From one of my favorite Family Guy episodes:

Alexander Graham Bell: Well, we did it Watson. What an afternoon. We finally perfected the first telephone.

Thomas Watson: Yeah, uh, hey listen, somebody called me today. Uh, whoever it was, said some very sexual things, very angry, sexual things.

Alexander Graham Bell: Oh, really? Probably just some teenagers somewhere... damn them.

Thomas Watson: Well, well that's, that's the thing. I mean, there's, there's only two phones, in the, well, in the world and one of them is in my office and the other one is in your office and those two didn't even exist until a few hours ago.

Alexander Graham Bell: Yikes, I could use a distraction right now.

Maybe a less-than-tasteful tribute, but humurous nonetheless (IMO)... :D

Douglas Coupland

2008-02-23T08:00:00.002-06:00

I believe Douglas Coupland is probably the greatest author of my generation - certainly my favorite born in the last 50 years. My wife and I just got through reading his latest book, The Gum Thief, and it's absolutely brilliant. His two best books, in my estimation, are All Families are Psychotic and jPod. The latter is now a TV series in Canada. If you're lucky enough to be a Canadian resident, you can watch the first few episodes here.

Noteworthy aside: When my wife and I figured out that only Canadians can watch Canadian TV shows on the Internet - duh! - we soon figured out that we're closer (driving distance) to Winnipeg than we are to New Orleans. Who says Kansas is in the middle of nowhere? Thus, it looks like we'll be doing a road trip when jPod comes out on DVD!!! 8^D

Anyway, if you are a bonafide Gen-Xer, I am willing to bet you will thoroughly enjoy Coupland's work. Happy reading!

Architects and Sound - Part Deux

2008-02-04T09:29:00.000-06:00

Sort of continuing the theme from Friday is this article I came across in Pro A/V. ...Sigh...

In case any non-acoustical types are reading my bLog, there is a very easy way to avoid acoustical and audio pitfalls on these types of projects. HIRE AN EXPERT...BEFORE the project is finished! Here are some links:

In the US, there's the NCAC.
In the UK, there's the ANC.
And there's always Google and the yellow pages, as well as the other acoustical groups, such as ASA and INCE, linked on the sidebar to the right.

Great places to start...and, in case I didn't mention: BEFORE the project is finished.

Architects and Sound

2008-02-01T16:53:00.000-06:00

Today's Cross•Spectrum blog entry is another good one. The coverage of the Livesound article was nice. And it reminded me of a couple of gems:

"Eighty-seven percent of sensory input is visual." - Architect to me after I introduced myself as the Acoustical Consultant on the project. Needless to say, it was all downhill from there. Of course, I did have a witty comeback: "Yes. And 75% of statistics are made up on the spot."

"No one has ever been saved by crown molding." - Worship audio guru Kent Morris in reference to allotting money towards decorative finishes verus acoustical finishes during a presentation for a NAMM acoustics for worship workshop several years ago. In other words: To hear The Word, one needs to hear The Word.

Acoustics & Climate Change

2008-01-29T13:55:00.000-06:00

I have to admit that I'm somewhat reluctant to jump on any bandwagon, let alone the most recent one related to global climate change. Of course, I am trying to be a responsible citizen of Earth. I am not a "climate change denier." But neither am I an avid Algore-ite. It's actually quite simple: My mental gag-reflex kicks in when anything scientific becomes overly politicized. But that's just me...and I am NOT going to bLog about my opinions on the quagmire of issues.

Nonetheless, here is a bLog for you with some blurbs about how the whole climate change thing has overlapped with the acosutics world:

For an entertaining exchange amongst acoustics folk (Savant included) on the issue, you can visit at least one (there are too many, lol!) hijacked Studiotips thread. :)
If you're in the green building biz - LEED and all that (not to be confused with LEDE, of course 8^) ) - then check out Michael Noble's piece in the Summer 2005 ASA newsletter, Echoes.
Finally, a favorite acoustical foam manufacturer of mine has now incorporated, of all things, soy components into their products to reduce carbon emissions, etc. (You still can't eat it, though.) Check out Studiofoam-eco at the Auralex site!

Elucidation Request

2008-01-24T16:28:00.000-06:00

Today's Cross•Spectrum blog post left me wanting, if have to say. And since I cannot figure out a way to comment there, I do so here. :)

First, I would like to know what's not to like about Cloverfield? Unless you suffer from motion sickness, I thought it was a very clever movie built around a tired old theme ("bad-thing-destroys-Manhattan"). My thought for the sequel: Another video is found that documents the same event from a different person's perspective. IMO, the whole thing wouldn't get old for at least 2 or 3 more movies.

Second, I have to concur, at least partly, about the B&K 2250. I say partly because I do like the sound recording to compact flash option. If you get a compact flash card with, say, 64 GB capacity, you can record (according to B&K's specs) over 185 hours of audio as 16-bit, 48 kHz WAV file(s). If all you need is a few hours - or even a full 24 - that leaves plenty of extra space for data. However, the major drawback to this (IMO) is that a 44.1 kHz sample rate does not appear to be an option. Guess the folks at B&K don't like to burn audio CDs...

(Of course, if someone would simply develop a way to attach a Type 1 mic and preamp to an somehow-record-enabled portable music player... But that's another bLog for another time...)

Another reason I concur is that there is HUGE feature that has been left out of the 2250: GPS capability. IMO, this needs to be a standard feature on all new SLMs from this point forward. At least on SLMs of B&K caliber. If they had included GPS and a way to access the meter remotely (Bluetooth, anyone?), it would deserve the hype.

Of course, over the years, a colleague and I have gone back and forth adding all sorts of bells and whistles to imaginary SLMs, only to conclude that what we really want is an acoustical automaton that replaces not only our bulky field survey equipment cases, but also replaces the operators (us), thus removing the need for us to have to travel with our bulky field survey equipment cases and go poking around cornfields, deserts, and well-to-do suburbs at 3 a.m.

But back to the real issue: What's not to like about Cloverfield???!!! :):):)

Dressed for (Acoustical) Success

2008-01-23T16:46:00.001-06:00

A little too late for Christmas, but I recently came across this garment, something all noise geeks will want to have in their closets.

Of course, if they develop matching pants, where do you think the microphone will go?

And, now that I think about it, wouldn't a hat make more sense? I mean, who listens with their chest hairs?

And speaking of chests (uh-oh), if a woman should don the Noise T, shouldn't there be some way to account for, um, "shielding" effects?

OK, I'm going to stop now.

Happy Asimov Day!

2008-01-02T10:34:00.000-06:00

On this day in 1920*, in that sleepy little burg we all know as Petrovichi, Russia, a sci-fi legend was born. If you've never read any Isaac Asimov - and even if you're not a fan of sci-fi - you owe it to yourself to at least add one (or seven) of his great works to your "to-read" pile. If you prefer galactic sagas, I suggest the Foundation novels. If you're a closet R2-D2 or Data fan, you can't go wrong with any of the Robot books.

Asimov was one of the genres most prolific writers. Even his non-fiction is simply oustanding.

So, I declare this Asimov Day - I hope yours is a good one!!!

*At least, this the the day that Mr. Asimov himself celebrated - his exact DOB is not known with any certainty. See Asimov's Wiki entry for more.

2007 in Review - Audio-style

2007-12-31T10:28:00.000-06:00

It's 31 December and I thought I'd bLog a quick review of some (IMO) notable happenin's in the world of music, audio, and acoustics in 2007:

I may add more later if I think of them. Happy New Year! <<8^)

Sunshine State Song

2007-12-28T13:47:00.000-06:00

I read today that Florida wants residents to vote for a new state song. The three finalists are "Florida - Where the Sawgrass Meets the Sky," "Florida, My Home," and "My Florida Home." I started thinking about what songs may have been runners-up:

"I Can't Drive 55"

"Air on a G-string"

"Blowin' in the Wind"

"Rock You Like a Hurricane"

"When I'm 64"

"The Heat is On"

...

Also today - and eerily related - a friend sent me a link to the dumblaws website. Here's an entry from the list of dumb laws in Florida:

"It is illegal to sing in a public place while attired in a swimsuit."

Ma Gray?

2007-12-27T08:57:00.000-06:00

The late 19th and early 20th century years were rife with innovation. The automobile replacing horse-drawn carriages; the phonograph putting Puccini in the parlor; Einstein telling us speed is in the eye of the observer; the list goes on and on.

As most history books, encyclopedias, and almanacs tell, it was during these years that Bell gave us the telephone and Marconi gave us the radio. Besides audio, these two life-changing inventions now apparently share something else: Controversy.

In the case of radio, it has been known for quite a while that Marconi most probably, um, "borrowed" the idea from Tesla. PBS has a nice little page on this.

Well, it would now seem that Marconi may have just been following Bell's lead. Personally, I can't wait for the book to come out; I'm a sucker for a good Whodunnit...Geek Style! Of course, I hope this doesn't mean a new sound level unit...the dG?

Airport? What airport?

2007-12-12T16:53:00.001-06:00

Got this Popular Science article emailed to me from a colleague. For those of you who like percentages when considering sound (I don't), this new jet would be roughly 99.999998% "quieter" - in terms of sound pressure - than most of the existing jets out there. Just think of how serene our surroundings would be if similar sound sources were equally reduced - in terms of sound pressure.

I could stand 50 feet from a garbage truck and never hear it.
I could get my leaf blower out, blow the leaves around my yard, and look like Luke Skywalker out there clearing a path using nothing but the Force.
There'd be nothing but the sounds of people walking and talking (screaming) into their cell phones along our cities' busy streets.
"Stealth" technology would take on a whole new meaning.

Interesting stuff to consider, to say the least... ;^)

Fresh Take on an Old Question

2007-12-11T10:54:00.000-06:00

I just finished reading David Brin's monumental tome, Earth. It's a near-future book, written in the late '80s with the action taking place in the year 2038. Brin's view of a future that is now 30 years hence is, in spots, far-fetched, but (IMO) he exonerates himself in the end by explaining that he did, indeed, take quite a few liberties with some elements. (It's simply hard to believe Miami will be underwater in the next 30 years. But hey, it could happen...)

Anyway, I just had to share one little gem with the 10*bLog(p²) faithful. A character in the novel having a pensive moment considering quantum theories, Heisenberg, and philosophy had this to share:

"Without observers, not only is a falling tree without sound...it's a concept without meaning."

Anyone in the acoustics biz has no doubt had to face the, "Well, what's your take on the falling tree?" question from inquisitive strangers / friends / family. Next time I get hit with that one, I have a new answer! :^)

Sound Objectivity

2007-12-04T09:54:00.001-06:00

My good friend over at Cross•Spectrum commented on yesterday's blog, and also opined on his own blog today.

The points that herb makes are excellent. (I wish I'd made some of them myself, particularly the one about the ANSI S12.18 standard...)

In repsonse, I'd first like to point out that my Baby/Bathwater blog should not be interpreted as my being in opposition of "nuisance"-style noise ordinances. Indeed, I believe that both objective and subjective ordinances are necessary. If the neighbor's loud party is keeping you awake at 1 a.m., I agree that there should be no need for the officer to have to dig out his sound level meter in order to issue a citation to the offender(s). Common sense should prevail.

But there are myriad instances where lack of an objective ordinance can hurt more than help, just like eliminating speed limits would hurt more than help.

My main point is that objective sound level limits should not be thrown aside simply because motorcycle noise is difficult for a law enforcement officer to measure. This is throwing out the baby with the bathwater.

Also, most people these days can operate a digital camera. IMO, the best way to support a noise citation for a loud motorcycle is simply to photograph the offender's exhaust when the citation is being issued. Since straight pipes or modified exhausts are illegal, it should be an easy enough thing to prove without any sound level measurement whatsoever! "It was excessively loud, and here's a picture of the offender's exhaust with the manufacturer's noise control measures having been removed."

If the offender really wants to fight the citation, a standard "pass-by" test can prove violation beyond a reasonable doubt. I would gladly offer up my services to conduct this test for my local law enforcement agency for a modest and reasonable fee. (Certainly less than the amount of the fine that would be incurred.) Further, I could probably be convinced to volunteer to train one or more law enforcement officers as to the proper methods to conduct the test, thereby saving them future costs. Measuring sound is difficult, no question. But a simplified version of the "pass-by" test - one that can prove violation without having to prepare a 20-page report (or follow an 18-page standard to the letter) - doesn't require an advanced degree in physics to conduct.

And once the word got out that the local police are able to perform a test that proves violation beyond a reasonable doubt, the loud pipes would begin to go the way of leaded gasoline.

At least, IMHO...but maybe I'm just too idealistic...

;^)

Baby? Check. Bathwater? Check.

2007-12-03T12:36:00.000-06:00

It seems several communities in Colorado just don't get it. To me, this clears the way for some smart aleck to propose that the objective speed limits should also be done away with on the roads in their communities. Since equipment and training for measuring vehicle speed is expensive and imperfect, it should be left to the law enforcer's judgment as to whether someone was driving excessively fast. Right?

************

Let the rant ensue...

Along the lines of the specific noise source in question, I must admit that I am having trouble understanding why motorcycle noise, of all things, is making an unwelcome comeback. It certainly seems to be in my neighborhood. But, the USEPA took care of this years ago. Putting aside the fact that excessive noise from motorcycles and modifications to a motorcycle's exhaust system are often prohibited by state and/or local laws, it's a violation of federal law to modify manufacturer-equipped noise control measures on motorcycles. IMO, that our country is seeing a resurgence of excessive motorcycle noise is a simple case of what happens when laws are not enforced.

Nonetheless:

If your motorcycle is excessively noisy, you are probably breaking the law. At the very least, it is your responsibility to make sure you aren't.
If you modify or replace your motorcycle's exhaust with anything, other than to replace the manufacturer's original equipment with its equivalent, you're breaking the law.
Straight pipes are illegal.
"Mufflers" designed to amplify exhaust noise are illegal. (And - btw - they are not "mufflers"; they're "amplifiers.")

I'm not one to impose my personal preferences on people. If you like to ride a motorcycle, be it for pleasure or otherwise, I think that's just fine. But you are not allowed to break the law while you're doing it. It's that simple.

If I have to wear a seatbelt, keep my vehicle maintained to a condition of roadworthiness, observe the posted speed limits, wear the proper corrective lenses, signal when turning, and generally obey the law when I drive my car, so should it be for you when you ride your motorcycle.

I was taught that driving is a privilege, not a right. IMO, this goes for motorcycles as well.

Random things for Today

2007-11-18T21:21:00.000-06:00

Random sound link for Today: http://www.sound101.org/index.php.

Random inquiry for Today (No. 1): Remember when Southwest had seats that faced backwards? Do they still have those?

Random thought for Today: If I were to create a Second Life, my propensity for all things Geek would most likely lead to it becoming my First Life.

Random musical suggestion for Today: Mary J. Blige - Growing Pains (in stores in December).

Random inquiry for Today (No. 2): Of all the possible catchy-songs-I-don't-want-stuck-in-my-head-all-weekend, why oh why oh why did Jeep have to pick Andy Kim's Rock Me Gently? It's bonehead moves like that that make me swear off a product...

Random acoustics-article-you-should-read Today.

Finally, Random advice for Today: In your life, strive to get at least one person to call you a sesquipedalian.

decialexanders re 20 microblaises

2007-11-11T11:07:00.000-06:00

Been catching up on some periodical reading lately. To that end:

If you're a Syn-Aud-Con member, check out Jim Sorensen's column ("Sorensen Sez...") in the Fall 2007 newsletter. It was right in line with all the bloviating I've been doing about the names of things. (The title of this blog was developed using Jim's concepts.)
If you subscribe to Sound & Vibration Magazine, you should check out the, IMHO, excellent S&V Observer piece from the September 2007 issue. If you don't get it, you can still read it online (PDF), albeit with a few typos.
Finally, I noticed some nice pictures of the post-production facility at Lakewood Church in (and on the cover of) the September 2007 issue of Church Production magazine. I happen to know that the live room acoustical treatments (visible through the control room window in the cover photo - which, sadly, I could not find a good view of on their site*) were installed back in 2005 by a really cool dude and a few of his equally really cool colleagues at Auralex and RBDG, Inc. A nice article - "Pillar to Post" by Dan Daley - about post-production in houses of worship accompanies the photos. Looks like you'll have to find/buy a back issue to appreciate it, though.

*See also a 2006 press release for a reasonably similar photo.

Tags of Steel...or nickel-plated zinc alloy, at least...

2007-11-05T19:46:00.001-06:00

In case I never said, I'm a complete Superman freak.*

To that end, I can hardly contain my excitement; I received my shipment of Superman dog tags today. Oh yes. I haven't been this excited since I bought my wife a Napoleon Dynamite pen that says "Sweet" or "Lucky" or "Whatever I feel like I wanna do; GOSH!" (et al) when you click it. Now, I can be a complete Kryptonian-übergeek and feel good about it, too. Superman dog tags are available at the WB store, they look like this:

and 100% of the profits go to the Christopher and Dana Reeve Foundation, which I've also added to my list of links to the right.

If you know any Superman fans, these would make a GREAT stocking-stuffer.

Go Forward.

*Home of Clark Kent (and Savant) is No. 5 on the list of reasons why Kansas is the coolest place to live. Sandwiched right between No. 4, Tsunami-Free for at Least 6 Million Years, and No. 6, I Have Fossils in My Backyard, Do You?

DST is BS

2007-11-04T08:20:00.000-06:00

Well, it's that time of year again. And since I have a blog this year, I get to share with you, the innocent reader, my loathing of the biannual tradition that is Daylight Savings Time (DST). There are so many things to despise here, I hardly know where to begin my rant.

Should I start by pointing out that a great number of people in the U.S. believe that we are actually "saving" daylight, thus magically increasing or decreasing the amount of daylight simply by adjusting our clocks? Ah, the power of the clock dial. If we truly had this much power with our clocks, none of us would ever be late to work again: "What? I'm not late; I set my clock back 10 minutes, so I'm actually early. Didn't you get my e-mail? I sent it to you later this afternoon."

Or perhaps I should start by pointing out that hardly a soul knows the exact origin of DST. Everyone from Ben Franklin (wrong) to farmers (wrong) to retailers (wrong) and so on has been attributed with giving us the "gift" of DST. (For the truth, see the Wiki entry on DST, or Michael Downing's book.)

There is no evidence that suggests DST is good for anything. It certainly has been proven to be bad for certain things, like international travel. It is unnatural. It has been blamed for an increase in traffic accidents. Computers, or, more likely, the humans programming them, are notoriously bad at keeping track of it. Case in point: Watching game 4 of World Series last weekend, I noticed that the scoreboard clock at Coors Field had already "fallen back."

Of course, studying its benefits is even more ridiculous than the concept itself. We're like a bunch of lab rats. Make the humans go from 24 to 23 hours every Spring and measure the effects. Gosh, it could lead to more traffic deaths. Let's do it anyway.

For a good portion of my life, I studied and worked in Indiana. Indiana used to be one of three states that did not observe DST, which suited me just fine, as you might imagine. I used to get a chuckle from out-of-state people who made a big deal about not understanding what time it was in Indiana. Like we were the backwards ones because we didn't observe the protocols for clock-changing that had been mandated by the government for reasons no one truly understands. But, alas, Indiana managed to take a big step backwards a couple years ago when, instead of leading the charge to abolish the practice of DST in the other 47 states, they conformed, jumped on the bandwagon, and joined the eastern time zone for good. Makes me sad, but I can't complain because I don't live there anymore.

I could go on about this for quite some time as I have given it entirely too much thought. (But, what the heck? I've got an "extra" hour today, right?) What it all comes down to for me is the measuring stick I often use when trying to ascertain the relative idiocy of a certain action. I call it, "What Would a Visiting Interstellar Traveler Say?"

Interstellar Traveler: What are you doing?
Savant: Setting the clocks in my house back one hour.
IST: Why?
Savant: Because it's Daylight Savings Time.
IST: That is silly. You cannot save daylight.
Savant: We do it twice a year.
IST: That is ridiculous.
Savant: So's electing anyone named Bush or Clinton to the White House, but we
keep doing that, too.
IST: That explains a little, but not enough. Humans are not intelligent. We will now annihilate the Earth.
Savant: Cool. Hey, nice tentacles, by the way. Would you mind getting that clock
in the den for me?

We don't need DST. If we want "more" daylight, we need to get out of bed earlier. Newsflash: Time is arbitrary. If the perceived amount of daylight (i.e., how much we see because we're awake) is really that important to us, I propose we split the difference between winter and summer, adjust the clocks ahead a half hour come next spring, abolish DST once and for all, and never have to deal with this clock-changing business ever again. (If I just lost you, then there should be a new law that takes away your legal right to own a clock.)

Of course, we do need something to remind us to change the batteries in our smoke detectors. After all, what better way to remind someone to change the battery in something that could save their life than to have them fiddle with all the clocks before they go to bed?

Resistance is futile.

It's Hallowe'en; Get Your (Acoustical) Geek On!

2007-10-30T10:28:00.000-05:00

If you’re not already watching it, I recommend CBS’ new comedy, The Big Bang Theory. I especially recommend it to anyone who falls, or has friends/family who fall, into the Geek/Nerd category.

This week’s episode was particularly hilarious as it had a Hallowe’en theme. One of the main characters, Sheldon, dressed up as the Doppler Effect. His costume was a centrally located circle representing a light source, with stripes representing waves of light at decreasing (or increasing, depending on the relative motion of the observer, of course) frequency eminating from the source. As an acoustician, I found this hilarious, especially when Sheldon was trying to explain his costume to other Hallowe’en party-goers: “You know;” [imitates a passing vehicle] “Nnyowm.” Fellow acousticians: How many times have you done that in your life?

This got me to thinking about other great acoustical Hallowe’en costumes:

• You could stand in place and bob up and down: You’re a Standing Wave. (To make it more obvious, you could simply stand in place and wave.)

• You could continually travel in a straight line from one side of the room to the other: You’re an Axial Room Mode. (You could get really creative if you wanted to be an Oblique Room Mode, but be careful not to break anything.) To enhance this costume, alternately raise and lower your voice to correspond to the appropriate sound pressure distribution.

• You could repeatedly repeat everything people say, lowering your voice with each repetition. You guessed it; you’re an Echo. This would be particularly effective if you only did it to the last syllable or three of any given sentence. Of course, with enough practice, you can simply repeat everything people say in a slightly lower voice.

• You could paint yourself and your clothes starting with red-orange around your mouth and moving through the ROYGBIV colors moving away from your mouth until your feet are violet/black: You’re a Spectrograph.

• You could get one of these for your head:

And one of these to wear around your neck:

And be a Sound Level Meter.

• Finally, not strictly acoustical, but you could get this printed on a T-shirt:

Then put a small loudspeaker in your pocket hooked up to a signal generator. Play a 1 kHz square wave through the loudspeaker and you can go around saying, “This is Only a Test.” People will love you.

Here are some more conceptual costumes you can ponder:

Fast Fourier Transform (FFT)
Helmholtz Resonator (Coke bottle, slat absorber, etc.)
Signal-to-Noise Ratio (SNR)
Sonar
Ultrasound or a Sonogram
Active Noise Control

Happy Hallowe’en!