Slashdot Mirror
See-Through, Paper-Thin Speakers
Cormac writes "Here's an interesting article about scienists in the Korean Institute of Science and Technology (KIST) who are developing see-through flat speakers which (they claim) could be rolled/folded up and put in your pocket or even be pinned to a wall." I wonder about the fidelity, but there could be some excellent potential here: it irritates me that my center channel is on my TV. Without getting a projector and putting the speaker behind a screen, something like this could just be built onto your TV. But can it sound good?
Those are electrostatics- these are piezos. Electrostatics operate on very high voltages (and very low amperages), and require stator screens. Piezos operate by one side expanding and the other contracting, mechanically pushing most of the speaker area forward or back. There are also center-driven planars (Sumo Aria, Museatex Melior) and line-driven planars (Magnepan).
I don't know what you'd have to do to get a huge plasma speaker that could carry bass, but I don't want to be around while you try it :)
In order to do composite drivers, you have to go with simpler crossovers, not more complex- phase relationships have to be dead simple, the normal rules for multi-element speakers are entirely reversed.
Electrostatics and planars do what they do not just by having the speaker handle all frequencies with one element, but by having the element behave more controllably than cone drivers. Use of very light elements can mean little or no overshoot or ringing at bass frequencies. That ringing is what would really create 'doppler' effects on the sound- having the speaker follow the path of the waveform as one unit does not cause any sort of distortion in itself.
The roll-up piezo speakers are likely to be fairly crappy sound, but this is mostly because they're lacking in any sort of solid stand or base to push against, and the piezo operates by flexing and going convex or concave. Clamp the edges and you'll get more bass and general fidelity.
I've experimented with these fairly extensively, and still am from time to time. DIYing center-driven stretched-mylar speakers is fun, but tricky to make useful. Here's what I learned:
DIY is fun
--
Care about electronic freedom? Consider donating to the EFF!
On the other end I've got two 10cm x 5cm cheapie speakers I bought at discount (old iMac color) that sound ok but tinny. For 5 bucks I can't complain, they're smaller then anything else & don't mess with any magnetic media near them.
As to on a laptop screen - this as been talked about for years but every time a problem appears. Most of the times the speakers just weren't very robust physically, certianly not up to the life of a laptop. Or they've required too much power or degraded quickly. Then there's the whole "transparency" thing - unless they're really really clear folks aren't going want to put a smoky layer of whatever over their screens, audio or no. From the article pics of this latest incarnation it looks pretty murky...
I don't read ACs: If a post isn't worth so much as a nom de plume to its author then I wont bother either.
... if he can spatially distinguish between a speaker on top of his TV and behind the TV.
How close are you sitting and how big is your TV? Unless you're talking a 36" TV and < 3' distance, I don't see how you can tell.
"Beware by whom you are called sane."
Potato chips are a by-yourself food.
Or someone else's sweater perhaps? (evil grin) Gives this sluggy comic a new shot at reality. :)
"You know, Hobbes, some days even my lucky rocketship underpants don't help" -- Calvin
Here's a DIY project for you...
Why not try to use resonance?? Products like the Bose wave use long resanator tubes to get decent bass out of two 1" speakers. What would happen if you used a resonator with the mylar stretched across it?? (An old drum body, etc...)
I realize that this will not correct the already low bass response, as there apparently are no surfaces capable of producing the long low waves, but should add depth and take away from the tinniness of the speakers. With contact on a wood resonator, percussion and bass should at least produce a pleasant woody thump.
Just a thought...
~Hammy
I have a very nice quality 5-piece flat planel setup at home ... the four flat tweeters around my system sound extremely good, even when cranked up very high... What makes these so unbelievable?
So if this speaker can transmit sound, it can receive sound, right?
Mount one to your monitor and connect it with a full duplex mic line to your computer. Use NetMeeting and you can get the ultimate video phone.
Now Microsoft (or the government, whichever lasts)can add some inconspicuous code and listen and watch everything you do.
Oh, no wait, that's 1984 isn't it?
"I always knew there was something fundamentally wrong with the universe." -- Arthur Dent
To reproduce low frequencies the speaker surface must move a fairly large distance. The problem is that this movement actual creates a doppler shift in the high frequencies, creating a "muddy" sound.
While this is essentialy true, it isn't the most significant problem with large panel speakers. These are large enough that the surface won't have to move much. (of cource if you make them small you're screwed).
Panel speakers traditionally got two problems:
They tend to be dipoles which means the got to be huge or have no bass. Once the path from the rear of the driver to the front becomes small compared to the acoustic wavelenght it exhibits an acoustic short which works to cancel and phaseshift LF sounds.
Also any driver which active surface is larger than the wavelenght of the sounds it reproduce will exhibit beaming and comb filtering since for a given point in space the path to two different points on the driver will be different. For large drivers the difference can become significant compared to wavelenghts and interference ensues.
Some panel speaker technologies also suffer from beeing very hard on the amps (el-stat).
In short it's hard to justify making a panel speaker.
Remember that it is a panel doesen't make it thin unto itself. If you don't want a dipole you still need the box, and if it is a dipole the problems above occurs and it will still have to stand out from the wall to avoid interference from back wall reflections.
Shawn Pack
For those who fight for it, life has a flavor the sheltered will never know.
Any substantial home entertainment system is going to have a great big sub sitting off in a corner anyway. Since it's a lot harder to tell which direction a deep bass tone is coming from than with a higher tone, I don't see this being a problem. Then again, I don't know where the actual cutoff point lies. Plus that volume issue bugs me... I need my matrix gunfights to be LOUD
Admittedly what's available now isn't flexible or transparent, but it is flat. I have a set of Monsoon speakers. Each satellite speaker has a normal cone-type midrange element, but the high-frequency element appears to be a clear piece of plastic printed with circuit traces and surrounded by magnets. In Monsoon's higher-end speakers, the satellite units are 100% flat-panel. Apparently the larger the panels are the lower frequencies they can handle. (makes sense)
I'm not sure whether Monsoon has this stuff patented or whether there just aren't many companies implementing it yet...
-- 2 + 2 = 5, for very large values of 2
yes, but they were HUGE. You need to move large volumes of air to get bass, and if you don't have throw, you have to substitute surface area.
may electrostats come with subwoofers for this reason.
Anyone remember the disposable Paper phones currently in design? We never thought those would replace cell phones (or heaven forbid, one of those option loaded corporate receptionist phones). But it's still a good idea because you can spend a few bucks on a paper phone if you need to make a call, and just throw it away when the time runs out.
:)
Same thing here with paper speakers. This isn't designed for watching The Matrix or Gladiator in all its glory. These speakers are better suited for cheap things when you just want any sound production whatsoever... Like talking advertisements in magazines...
On second thought maybe this isn't a good idea.
-Ted
and now paper speakers...
Plus, there's not mention of frequency response, wattage, impedience, nuthin'.
I doubt it's real (or if it is, it's real stupid, or real bad).
-- You can't idiot-proof anything, because they're always coming out with better idiots.
These speakers, if they come about well enough, will be used in places where they're needed, and not in places where competing technology kicks more ass. It's pretty much that way anywhere with any product. I see the following good uses for these:
- Computer speakers inside the monitor/laptop screen. Handy, space conservative, and powered by the monitor. Not great sound, but for sound effects and watching CNN live it should be fine.
- Center channel speakers on a 5.1 surround system. Get one of these on the screen of the TV and you have the perfect center channel speaker placement. Heck, get really innovative and have several over the surface of the TV, and you can get conversations between two people sounding like they are coming from either side (not that stereo technology doesn't do a lot of this already)
- Quick-'n'-easy party-hardy materials. Small, portable CD/MP3 player and a small bag of rollup speakers. Set player ontop of empty beer case, unroll speakers, stick to wall with stickytack, and wha-lah! Instant tunes.
- Applications where sound is wanted but conditions are rough: On rafts, boats, skis, snowboards, umbrellas, patios, bathtubs, showers, underpants...you get the picture.
- Talk about a revolution in children's books. Pages that have speakers right in them. neat-o.
:)
They're not likely to please the audiophile in your midst for hi-fi applications, and anyone watching something like Matrix on them should be shot. But they'll have their (rather vertical) niche and work great....I think it's cool!Blog,Twitter
Flat speakers (aka electrostatic speakers), though not exactly mainstream, aren't unusual in the audiophile world. If you're really curious, you might check out Magnepan or MartinLogan or Quad. Also try looking for reviews at Stereophile. There used to be a user-review site at www.audioreview.com, but it's not resolving for me so maybe they're offline at the moment.
--
314-15-9265
We don't all have a pair of little speakers and a subwoofer on the floor.. Some of us would like to hear some midrange as well.
----------
Never underestimate the bandwidth of a 747 filled with CD-ROMs.
Now when im short on paper i can use my speakers to smoke.
For most hifi systems this solved by having separate cones for the high end, midrange, and low end (tweeters, subwoofers, etc.).
My guess is that these simply won't be suitable for audiophile-level quality sound reproduction. Their best use would be for portable systems where sound quality isn't as big an issue, or computer speakers since we're all used to crappy sound anyway.
Karma: Bored. (Thinking about resurrecting the "Anyone else is an imposter" joke.)
We've all got a pair of little speakers for high notes, then a big subwoofer on the floor. If they can make a better pair of tweeters, why gripe? As it is, mine are on the verge of falling of the desk because they can't fit next to my 21" moniter.
The only "intuitive" interface is the nipple. After that, it's all learned.
"The question of whether a computer can think is no more interesting than that of whether a submarine can swim" -EWD
Reach for a kleenex and hear ads for the latest cold medicine as you blow your nose!
And of course, new at Spencer Gifts:
Talking toilet paper! With hilarious phrases like 'Man it's dark in here' and 'you thought YOU had a shit job'!
Chesty-wet-babe posters will now spout 900-ads at regular intervals.
Ok my karma is maxed out. When do I become Enlightened?
I work to oppose software patents -- look at the little write up I did a month back on the M$ web poll patent. Know what facetious humor is?
CHoad.
Vergil Bushnell
Insects and Grafitti Photos
What articulate, yet visceral rhetoric!
What deft use of sandbox-cliches!
Vergil Bushnell
Insects and Grafitti Photos
Your post didn't irritate me at all - it was the anonymous troll after you.
Sincerely,
vergil
Vergil Bushnell
Insects and Grafitti Photos
- Ever been to a large protest or demonstration? Groups with axes to grind are typically under-funded, and habitually rely on tinny Radio Shack megaphones to "get the word out" - a marginal improvement over shouting, given ambient street noise. With these speakers, a dissident group could easily seed a crowd with plastic amplifiers taped to their ubiquitous posterboard placards.
- Pack a stack of these piezo-electronic sheets in your backpack, find an abandoned warehouse and a tube of super-glue and voila! Instant rave!
- Promotional companies that currently wheat-paste metropolitan walls with repetitous movie/concert fliers might find a way to paint their advertisements on sheets of the aforementioned plastic film with a flat EEPROM backing, thereby augementing their garish displays with short bursts of sound. Wait, I should patent that idea.
Sincerly,
Vergil
Cluebot.
Vergil Bushnell
Insects and Grafitti Photos
The problem with these existing speakers, critics say, is that while they do a good job of reproducing high-frequency sounds, they often are not substantial enough to produce deep bass sounds, or play at high volume.
"Even with quite large ones, which I've got a pair of them in my living room, they need a bass reinforcement," says David Pearce, a research fellow in functional materials at the University of Birmingham in England who specializes in piezoelectric ceramics. "Hearing these sort of panel speakers individually, they always sound kind of tinny. But then you put them together with bass support and you say, 'That sounds pretty good, actually.'"
Well, it was nice until that part... No volume and no loud bass, I'll stick with what I have, thanks.
Mooniacs for iOS and Android
I'm not exactly sure of the properties of these speakers but i'm guessing they'd still have some magnetism built in or maybe i'm just wrong. If it is the case then they'd need to be shielded if you wanted to place them right on top of a tv or computer with a crt monitor. And if it would be that close you'd have to have something to shield it out with, thus making it clear useless. Am i wrong or could this be a potential problem?
What would DJ's and their ilk be able to do with this (ahem) musically?
instead of scratching a record/cd you could do tons of dopplar effects by f'in with a thin flexible speaker...
Let's see DJ scribbles (or whatever) get down with that!
instead of "scratching" it will be called "tearing" or "folding" a phat beat=P
sounds silly but plausible to move a speaker around for effect (See leslie speakers, or their "virtual/electric" bretheren of phase shifting audio devices phasers, flangers, and chorus')
*Shrug* YMMV
E.
Build Your Own PVR/HTPC news, reviews, &
They do need about 30% more power to drive them tough.
Another important thing is that they cannot be placed against the wall because that kills the sound. So altough they are thin ( about 1'' ), they need a foot of clearence behind them. I wonder if the object of the article does better in this respect.
-- look, cheese ahoy!
Seriously though, I can see a bigger market in the home theatre market rather than in the laptop computer market. Really, when is the last time a laptop user has complained about the huge speakers on his/her laptop that are taking up valuable space and weigh a ton?
I love the smell of Karma in the morning
I love the smell of Karma in the morning
Careful what you say....
I Browse at +4 Flamebait
Open Source Sysadmin
For something really cool, sometimes you have to look at older technology, like the plasma speakers described here.
The idea is that the shape/size of a flame can be influenced by a high voltage signal, and the resulting changes in the flame are broadcast as a high fidelity sound. Here's a quote from the above site
There's not much bass to these, but boy are they cool looking!And, as an added bonus, you get to play with nifty Tesla coil technology.
These are true Geek Speakers.
Help find a cure for Gidget.
Using transparent speakers is a backward aproach. Better to use acousticly transparent projection screen, and place your choice of speakers behind it. This product is available now. Don't remember manufacture, but I believe that it showed up in Auido Visual Interiors issue that featured Fabio's system.
Many a long talk since then I have had with the man in the moon; he had my confidence on the voyage. Joshua Slocum
Paper thin material that is good for base rumbling. I see the condom industry latching on to this one.
But Yogi, the RIAA won't like that.
I've seen a whole pile of posts and people thinking that you can "wallpaper" your room or put it on your screen. Think for a second about how sound is made from speakers (or anything for that matter): by vibrations. If things vibrate, it means that they cannot be attached directly to anything except at the edges. You cannot "wallpaper" your room because all of the vibrations would be absorbed by the wall. You could however hang a sheet of this slightly away from the wall, thus giving it room to vibrate. The same thing would happen with a TV screen or your computer monitor. I don't know about you, but the thought of the glass of my screen vibrating at 12,000+ Hz as someone hits the high notes doesn't sound like a very bright idea.
Also, I have here with me a set of Monsoon MM1000s, which are flat panel speakers. Compared to my ($1400, not the best but good IMHO) stereo system at home they sound like crap, however I'm currently in France and I wasn't going to bring my huge towers with me. The flat panels are great for portibility, and considering their size they're really good sounding too. The problem is that you still need an amp for all of this, and the flat panels cannot produce low notes very well at all, so you'll also need a subwoofer.
In any case, speaking as a pseudo-audiophile, in my experience real speakers are still FAR ahead in the game when it comes to raw sound quality. If you want something easy to hook up to your TV or computer to play quake or listen to MP3s, then you can get by on something like this. However if you want quality then you still have to use conventional speakers, and I can't see that changing any time soon, but then again, what do I know?
I saw 21 U.S.Marines, in full dress, with rifles, fire a gun salute to the outgoing president, and every last one of them missed!
If God gave us curiosity
This is no technological breakthrough. I worked with a stereo manufacturer in the mid-1970s that manufactured thin film speakers. The speakers were a thin film of mylar with a metal surface that was applied by vapor deposition. They got the technology from NASA, as part of the FedGov's technology transfer program. The speakers had good bass response too. The manufacturer went out of business, but I know a couple of public places that still have the speakers installed and working, 20+ years later. The best thing about these speakers was that you could make a speaker 6 feet long and 0.5 inches wide, instead of a point source like a speaker cone that radiates in a spherical pattern, the sound radiated in a cylindrical pattern. Channel separation was excellent, as was spatial accuracy.
The koreans are making one huge misrepresentation, though. These speakers will never roll up, then unfold and just tack to the wall. You MUST keep the film taut in order to produce optimal sound. If you bend the films, the surface coatings break. And read the article closely. They haven't "invented" any new speaker technology, they've invented a new way to bond the electrodes to the surface. Whoop de doo.
you mean you can make clothes that act as a loudspeaker
riding the subway is hard enough already!!
that said, think of the applications for screwing with people if you could make your sweater talk... or a window... or a mirror.... oh my.
sorry, need to go make devilish plans...