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Stretchable, Flexible, Transparent Nanotube Speakers

timothy posted more than 5 years ago | from the buzzword-bingo-now-proven-soluble dept.

Music 76

An anonymous reader writes "Chinese researchers have realised that a sheet of nanotubes behaves like a speaker when you send an audio current through it. The technology opens the way for a range of new versatile speaker systems. A video shows the speakers in action — some are stretched, one has even been sewn into a flag."

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Audio wallpaper? (2, Interesting)

wcrowe (94389) | more than 5 years ago | (#25629063)

I wonder how long before this technology is affordable?

Re:Audio wallpaper? (-1, Offtopic)

Anonymous Coward | more than 5 years ago | (#25629117)

It is the FART which encompasses god and the REASON she stinks!

Re:Audio wallpaper? (2, Funny)

TheRealMindChild (743925) | more than 5 years ago | (#25630007)

Not when you account for how many Monster cables you'd need

Re:Audio wallpaper? (1)

xTantrum (919048) | more than 5 years ago | (#25631063)

But more exotic uses might see nanotube sheets stitched into clothing to create "singing and speaking jackets", Fan's team thinks.

only in china would this seem more exotic, like i don't already have enough noise pollution in the city and dumbass individuals on their cellphones yapping away. Now i need to have dumbass num 2 booming the latest britney pop crap from his jacket.

Rick Roll of Wallpaper (1)

jbezorg (1263978) | more than 5 years ago | (#25633047)

But the thought of someone's clothes Rick Rolling them brings an evil grin to my face.

Re:Rick Roll of Wallpaper (2, Funny)

glittalogik (837604) | more than 5 years ago | (#25633927)

Ooooh never gonna zip you up
Never gonna tie you down
Never gonna twist you round and half-Windsor you
Never gonna make you crease
Never gonna say drip-dry
Never gonna catch in your fly and hurt you!

Re:Rick Roll of Wallpaper (1)

jbezorg (1263978) | more than 5 years ago | (#25642713)

"Run with it, like a small boy in a field." ~ Nigel Tufnel

talking billboards? (1)

eleuthero (812560) | more than 5 years ago | (#25631455)

It seems to me it will start out at a high price for limited exposure advertising whatnot--maybe not as billboards, but certainly we'll be seeing a lot fewer sandwich board guys and more stationary stationery yelling at us to buy company x's product

It's True (-1, Troll)

Anonymous Coward | more than 5 years ago | (#25629073)

McCain sucks and Obama blows!

Re:It's True (1, Funny)

Anonymous Coward | more than 5 years ago | (#25629119)

pics or it didn't happen.

Natural progression (1)

MaxwellEdison (1368785) | more than 5 years ago | (#25629103)

So now we will elevate our American kitsch [wikipedia.org] from Billy the singing Fish to Wanda the singing Fishnets.

Oh fuck!!! (1)

rodrigoandrade (713371) | more than 5 years ago | (#25629137)

Just wait until some obnoxious advertisers (car dealerships) get a hold of this tech...

Re:Oh fuck!!! (0)

Anonymous Coward | more than 5 years ago | (#25634619)

It's going to be HUUUUUUUUUUGE.

Amazing (1)

sakdoctor (1087155) | more than 5 years ago | (#25629141)

This is going to revolutionise the telescreen. They can be made in china, then installed all over America, the UK and China.

Sound Quality/Better speakers (2, Interesting)

phantomfive (622387) | more than 5 years ago | (#25629261)

This is awesome! The problem with conventional speakers is the have huge difficulty dealing with subtle differences in volume. This means the tone color of recorded sound is never as interesting as real sound. It also gives problems when recording orchestras that get loud and soft. Check Beethoven's ninth symphony [youtube.com] for an example, it starts of as soft, like a single instrument tuning, the grows into a deafening roar, whereas the contrast is not nearly as emotional and exciting on a speaker, meaning we miss out if we can't afford our own pocket-orchestra.

In addition, if you click on that link, you will hear violins. However, those violins will not sound like real violins. There is a whole spectrum of musical interest that must be flattened out to get this in a speaker.

Now, however, carbon nanotubes might be the key to unlocking giant sound in your living room. Exciting times!

Wow, I haven't been this excited about new technology since I saw a lazerdisk. And that was just because it was big and shiny.

Re:Sound Quality/Better speakers (3, Informative)

pz (113803) | more than 5 years ago | (#25630363)

Sigh. It's great that you're excited and all, but just because there's a new technology for turning electrical input into mechanical work doesn't mean it is an advance in speakers. For example, piezoelectrics were touted as the be-all-end-all for speaker design when they came out. But, it turns out, they are rather bad at being designed into speakers, and even then, they aren't that accurate (although there are certainly exceptions).

The fundamental problem in speaker design is the inescapable mismatch of mechanical impedance between the relatively solid (ie, low mechanical impedance) speaker and the relatively non-solid (ie, high mechanical impedance) air. Using horn loading helps this a lot (the best speakers I've ever hear were horn loaded) as this serves as a mechanical transformer between the speaker and the room air. But what helps more than anything else for a given amount of engineering effort and cost is doing all of the bandpass filtering well before the final amplification stage and having exactly one acoustic driver per amplifier output stage. (If you don't already understand the reasons for this, just ask, I'd love to tell you about them!)

Now, will a curtain of this nanotube stuff work as a speaker? Sounds probable. Will it work well? I doubt it, since to accurately reproduce sound, the actuating mechanism (ie, the cone in a conventional speaker) needs to be as rigid as possible so that the acoustic wave it produces accurately corresponds to the electrical signal delivered to it. Internal distortions in the actuating surface (waves on the cone of a conventional speaker, or on the surface of this nanotube stuff) distorts the output. The larger the actuating surface, the more important its rigidity (read: it needs an extremely low internal mechanical impedance).

The ideal sound source for reproduction is a physical point, not a sheet. The reason speakers have physical extent, rather than being points, is the coupling issue touched upon above: they need to have extent that is comparable to the wavelength they are trying to reproduce in order to have sufficient coupling to the atmosphere -- unless an acoustic coupling mechanism is used, like a horn.

Re:Sound Quality/Better speakers (3, Informative)

phantomfive (622387) | more than 5 years ago | (#25630713)

That was an extremely interesting post, but these carbon-nanotube speakers are not vibrating at all! Read the article, they put a laser vibrometer on the thing, and didn't detect a single movement. Now, you have to admit that's pretty great. They think it is happening because of rapid oscillation of temperature, which is what happens with a thermophone. [answers.com] Which is an obscure little thing I had never heard of. They unfortunately don't mention anything about sound quality, but it at least matches youtube's! The idea of carbon nano-tube speakers is something I had not considered, but is definitely cool. I was actually, believe it or not, daydreaming about better headphone speakers last night. Not that I actually have any clue how to do it.

Re:Sound Quality/Better speakers (2, Informative)

ceoyoyo (59147) | more than 5 years ago | (#25630795)

While it doesn't necessarily mean it will make a good speaker (the sound on the video sounded pretty bad, but that could be because of the music chosen, the recording, or the video player), but according to the article the mechanism of sound production is not mechanical. Most of your points are quite true when you're actually vibrating a solid to produce the sound, but don't apply otherwise.

Re:Sound Quality/Better speakers (1)

Falconhell (1289630) | more than 5 years ago | (#25633647)

Quite so,

With you 100% on the active xover thing.

In horn loaded systems, an actice xover, combined with a design that keeps the drivers in their pistonic motion range is excellent.

Many years ago I had the pleasure of using Martin audio horn loaded system and it was stunning. The spread was excellent. you could het he same tonal balnce in most of a room.

Just bi-amping a 2 way system brings ahuge improvement!

Re:Sound Quality/Better speakers (1)

Velocir (851555) | more than 5 years ago | (#25636165)

WTF

Re:Sound Quality/Better speakers (2, Insightful)

4D6963 (933028) | more than 5 years ago | (#25630393)

Huh... aren't you basically just complaining about a lack of dynamic range which you can blame on the fact that you don't actually play CDs at 110 dB as in concerts? Excuse my ignorance, I'm not an audiophile, just a software engineer specialised in sound processing.

Re:Sound Quality/Better speakers (1)

ceoyoyo (59147) | more than 5 years ago | (#25630757)

Not to mention YouTube isn't exactly the paragon of high fidelity audio (or video). Plus most recordings take into account that you're unlikely to want a full orchestra playing in your living room, so they compress the loudness range so you can still hear everything and your neighbors don't have you arrested.

Re:Sound Quality/Better speakers (1)

4D6963 (933028) | more than 5 years ago | (#25637203)

I didn't even pay attention to that detail. YouTube has the worst sound ever, i.e. an awful automatic gain, plus bad compression.

Re:Sound Quality/Better speakers (1)

phantomfive (622387) | more than 5 years ago | (#25631011)

Nope. It is not a matter of volume, I can easily destroy my hearing with headphone speakers. I was actually complaining about the lack of dynamic sensitivity.

If you pay attention, a lot of dynamic subtlety is lost in recording. Listen to the fourth movement of Beethoven's ninth, and listen to how the bass solo is almost completely impossible to hear, unless the volume is turned up. If it were live, you would be able to hear it still, although softly. And you would be able to hear the expression as the bassist played, slightly louder and slightly softer. It is known that speakers have trouble reproducing this effect.

It is still there, though less noticeable, in louder passages when the tone color of different instruments is lost. The trumpet just sounds kind of flat. This is because what gives an instrument 'color', what makes it sound different than a Basoon, for example, is subtle differences in the sound wave, which gets flattened out somewhat in recording. If you want to notice this effect, listen to recordings of trumpets and other brass for a week. Then go to a live concert: even if it is just a high school concert, I guarantee you will notice a difference.

hope that clarified a bit for you.

Re:Sound Quality/Better speakers (0)

Anonymous Coward | more than 5 years ago | (#25632257)

This is mostly due to the quantization of the audio into digital recordings (or similar inherent noise in analog systems) and complicated even further by lossy compression measures common to almost anything you will find on the web.

Try finding a LPCM 24 bit recording (proper DVD audio) of that solo on same speakers and see if it makes a difference. If you use a decent set, I bet those speakers arent the weak point.

Re:Sound Quality/Better speakers (1)

4D6963 (933028) | more than 5 years ago | (#25637263)

Utter bullcrap, regarding quantisation, as the noise it brings is -96 dB (for linear 16-bit sampling). There's more noise brought it at any other point between the CD and your brain. And anyone who says they can hear the difference between a DVD audio and a CD audio lies, is a fool, or a bat.

Re:Sound Quality/Better speakers (1)

4D6963 (933028) | more than 5 years ago | (#25637233)

I was actually complaining about the lack of dynamic sensitivity.

What on Earth is 'dynamic sensitivity'? Sounds like a BS term to me.

If you pay attention, a lot of dynamic subtlety is lost in recording.

Again, a BS term. What you seem to be talking about regarding the bass solo is a poor mastering, i.e. a poor equalisation or a poor capture of the bass solo to begin with. Anything else you complain about can be blamed on a poor mastering. It has nothing to do with speakers, unless you have shitty ones.

Re:Sound Quality/Better speakers (1)

phantomfive (622387) | more than 5 years ago | (#25637637)

What you seem to be talking about regarding the bass solo is a poor mastering

I know what I'm talking about. I am not talking about a single bass solo, I am talking about more than 20 years of experience listening, experiencing, and playing classical music. I am talking from experience with hundreds of different speakers, mikes, and amplifiers, in and out of recording studios. I am not talking about just myself, I am talking about the shared experience of many technicians in the field.

Now look, I gave you an experiment you can use to begin to develop your own sound awareness, and you can either take it or leave it, but calling my stuff BS isn't an option.

It has nothing to do with speakers, unless you have shitty ones.

The speaker is one link in the line of sound reproduction. An extremely important one, and better speakers would definitely be a cause for great rejoicing. And of course we don't know the potential of this stuff, but imagine if even the cheapest car stereo had awesome speakers.......wouldn't that be the coolest thing ever? Absolutely. It would do marvels for the recording industry.

Re:Sound Quality/Better speakers (1)

4D6963 (933028) | more than 5 years ago | (#25648813)

Like I said I'm a software engineer. Only phenomenons that can be described mathematically interest me, I'll dismiss anything else as psychoperceptive bullshit. You can swear you can hear what you're talking about as hard as other audiophiles swear that putting an audio CD in the freezer gives the music a softer sound or that they can hear the difference with DVD audios, that's not going to convince me.

But if you can't explain what you're talking about any better and have to resort to boasting your credentials instead... The thing you said about "conventional speakers [having] huge difficulty dealing with subtle differences in volume" is bs, and you won't get anything much better than the best speakers you can get now, no matter what. If there's anything wrong that's not the speakers.

Re:Sound Quality/Better speakers (1)

phantomfive (622387) | more than 5 years ago | (#25657031)

Like I said I'm a software engineer. Only phenomenons that can be described mathematically interest me, I'll dismiss anything else as psychoperceptive bullshit.

Do you believe in love? Have you heard of Godel? [wikipedia.org] There are things that are true that can't be proven, and things that don't necessarily fit in a mathematical format.

You can swear you can hear what you're talking about as hard as other audiophiles swear that putting an audio CD in the freezer gives the music a softer sound or that they can hear the difference with DVD audios, that's not going to convince me.

You don't have to take my word for it, you can hear it for yourself. Try it.

The thing you said about "conventional speakers [having] huge difficulty dealing with subtle differences in volume" is bs

What makes one instrument sound different than another? Why does a clarinet sound different than a coronet, even when playing the same note? It is because they play the overtones of the pitch come at different intensities in different instruments. Sure, if a coronet is playing an A, you can tell it's an A on any speaker. But it is the subtle differences in overtones that makes such a huge difference between instruments, that gives them color, and it is unfortunately not accurately reproduced by any of today's speakers. Listen, you can hear.

Re:Sound Quality/Better speakers (1)

4D6963 (933028) | more than 5 years ago | (#25661629)

Like I said, psychoperceptive bullshit. "Listening to it" is not an answer, because you can hear whatever you want. That's why there's a difference between blind tests and what people claim for their own observations. And there's nothing about sound that isn't mathematical, invoking GÃdel is completely out of place.

What makes one instrument sound different than another?

Very generally and basically, harmonics, envelope, or when there is noise then frequency profile (or "colour") of the noise. Pretending that speakers affect these in any other way than by bringing in their frequency response (which can be alleviated by calibrating the speaker), noise or non-linear distortions (which are negligible on good quality speakers provided you stay within specs) is utter audiophile bullcrap. You sir must be a kook, but don't worry, so are all your colleagues.

Re:Sound Quality/Better speakers (1)

phantomfive (622387) | more than 5 years ago | (#25663447)

Like I said, psychoperceptive bullshit. "Listening to it" is not an answer, because you can hear whatever you want.

Any true scientist is not afraid of an experiment. Suit yourself.

Re:Sound Quality/Better speakers (1)

4D6963 (933028) | more than 5 years ago | (#25665499)

Wow, you really don't get it do you. Non-blind tests (i.e. yourself listening and looking for what you want) are worthless. Besides even if you did a real blind test it would be worthless, because it would prove that what you're talking about is an inherent limitations to speakers. I'm sure that you hear what you say you hear, the problem is that you can't explain it, and resort to blaming it on the nature of speakers, which is baseless and not even an explanation.

Re:Sound Quality/Better speakers (1)

phantomfive (622387) | more than 5 years ago | (#25671515)

You are right, there are many places in the recording and reproduction process where things can go wrong. If you tell me the microphone causes problems, I will believe you, and agree with you. If you tell me the digital audio converter is causing problems, I will believe you. I personally cannot distinguish between 16 and 24 bit audio, so I suspect that the file formats we use are not causing problems (although a poorly encoded mp3 can be hell; listen for a crisp, clear cymbal....they quickly become muddy in bad mp3s).

The speaker is the end of the line (unless you are deaf). It's an extremely important component, and if you are doing MIDI, which is computer generated sound, it is probably the most important part (yeah, yeah, amplifiers, wires, etc). Doing a better job on the miking is important too. If this makes better speakers, heck, if it even makes the low end speakers better, so that every dude has high quality sound reproduction in his pickup, then who could not be happy about that?

Re:Sound Quality/Better speakers (1)

4D6963 (933028) | more than 5 years ago | (#25684267)

That is all very true! And yes, unfortunately in the real world speakers are hardly ever calibrated (that is their frequency response is compensated for so that it's flat) and even if they were their environment plays a big part, as well as where the listener is in that environment.

So basically it's not so much the speaker itself the problem, but calibrating it (and you'll have a hard time to find any automated process to do it) and using the calibration data. I looked into it a couple of years ago and implemented some stuff but it's not simple. Because a microphone isn't calibrated either, in order to get the frequency response for your speakers in the setup you want from the position you want you basically need to do a bunch of recording using the microphone, your speakers to calibrate and something else that in a recording acts like the microphone and in another acts like a speaker. Then do some frequency domain equation based on the recordings, and then you get an impulse response that you should theoretically deconvolve your sounds to be played through your speakers with, how is the question ;). A sad thing that the reality of the necessity of calibrating speakers is so unknown and hard to achieve..

So like I said calibrating speakers depend on too many different things, however theoretically you could have headphones that are already calibrated, because the environment there (your head/ears mainly) varies little, but I don't think any such thing exists. If I wanted to find out if it does I'd ask in relevant USENET forums like rec.audio.* or comp.dsp. I know more about theoretical aspects than about what's out there to be honest. If you find anything interesting let me know ;).

Re:Sound Quality/Better speakers (1)

phantomfive (622387) | more than 5 years ago | (#25743439)

Yeah, I've been thinking that really the best chance at good sound quality is headphones.....I've heard these are really good, [amazon.com] but I haven't gone around trying every earphone available. Still, if this technology makes good sound cheaper, available for everyone, then that will make me happy. What is the point of recording great sound if most people can't even hear it?

Re:Sound Quality/Better speakers (1)

phantomfive (622387) | more than 5 years ago | (#25671873)

Oh, and incidentally, there is always the possibility that somewhere there is some super-awesome speaker that I haven't heard of, that totally rocks your socks. If that is the case, I humbly apologize and if you happen to know of it, would love to know which one it is.

Re:Sound Quality/Better speakers (1)

Mprx (82435) | more than 5 years ago | (#25630709)

Thin film speakers already exist, although the film is held between rigid electrodes:

http://en.wikipedia.org/wiki/Electrostatic_speaker [wikipedia.org]

The low mass is an advantage for accurate sound reproduction, but these speakers are impractical in most cases. I expect the nanotube speaker will have similar characteristics.

Re:Sound Quality/Better speakers (1)

rcw-home (122017) | more than 5 years ago | (#25630949)

The problem with conventional speakers

You misspelled "dynamic range compression" [wikipedia.org] . The CD format has >90dB of dynamic range - more than your ear can hear in most environments. And if everyone was listening to CDs in their own private listening room, and didn't knee-jerk judge louder music to be better than quieter music, then that's how music might still get produced today. But they're not - music is listened to by people like your coworker, trying to play it just loud enough so they can hear the song in their cube but so that you're not bothered by it in yours, or in their cars over the sound of traffic, or at a rock concert where you can't hear yourself yell, etc. None of those people would be able to hear that single instrument tuning at the start of Beethoven's ninth in a reference recording.

It's certainly not a problem with speaker technology!

Re:Sound Quality/Better speakers (1)

phantomfive (622387) | more than 5 years ago | (#25631521)

No, you are wrong. I may have not written clearly enough, though.

There is a whole community of people, who tend to listen to classical music, that is EXTREMELY interested in precise musical reproduction. They know what an orchestra sounds like, and they know a CD doesn't reproduce it very well. They will get annoyed if the sound is bumped up just to sound louder.

Recorded violins just don't sound like real violins. There are a number of reasons for this, but I will give you the same experiment I gave the other guy to verify this:

spend a week listening to brass music. Trumpets, horns, etc. Then go to a real brass concert. You will hear a clear difference. The live instruments will sound so much more colorful and alive, even if they are just played by high school students. Try it.

Re:Sound Quality/Better speakers (1)

rcw-home (122017) | more than 5 years ago | (#25631783)

Recorded violins just don't sound like real violins.

That's a waveform problem, not a "subtle differences in volume" problem. Address the individual links in the chain until the quality problem is solved. It will probably be expensive.

And yes, of course I've attended live classical music.

Re:Sound Quality/Better speakers (1)

phantomfive (622387) | more than 5 years ago | (#25631899)

Good, glad to see you know what I'm talking about. The thing is, every wave is just a series of different pressure levels, or volume levels. To see what I mean, try experimenting inserting values into to /dev/audio. You probably already know, though.

And yes, the speaker is just one link in the chain, but a very important one, and honestly, I am quite excited about the prospect of better speakers. If this works out, it will be, if you allow me the colloquial expression, awesome!

Re:Sound Quality/Better speakers (1)

mikiN (75494) | more than 5 years ago | (#25633617)

$ cat vmlinux > /dev/dsp

and hear what Linux really sounds like :-)

(You probably know that /dev/audio by default puts audio through a really ugly mu-law decompressor that makes anything sound horrible, even proper Sun .au files.)

Audio debugging is a fine art and can be quite a rewarding experience (if your musical taste permits), in paricular for loop optimization, distinguishing freezes from loops and such.

Re:Sound Quality/Better speakers (1)

mikiN (75494) | more than 5 years ago | (#25633751)

*Audio debugging: Sending specially crafted debug messages from your software into /dev/dsp. Sometimes more useful than wading through tons of debug messages, in particular when dealing with a large number of iterations or timing constraints.
*Alternative: video debugging: Sending debug output directly to the framebuffer or certain video registers.

Re:Sound Quality/Better speakers (2, Insightful)

blincoln (592401) | more than 5 years ago | (#25632027)

There is a whole community of people, who tend to listen to classical music, that is EXTREMELY interested in precise musical reproduction. They know what an orchestra sounds like, and they know a CD doesn't reproduce it very well. They will get annoyed if the sound is bumped up just to sound louder.

The problem with most of that type of person is that they refuse to participate in and/or accept the results of double-blind tests to see if they are perceiving something that's actually different or it's a psychological effect.

Anyway, the main issue I'm aware of in terms of dynamic range isn't related to speakers or microphones. It's that all of the standard digital audio systems I'm aware of use linear instead of logarithmic encoding. Digital cameras are the same way. Our ears are logarithmically sensitive, and the exposure model retained from film cameras is too.

For whatever reason (simplicity, I assume?) digital audio and imaging systems use a linear model. This means that in the case of digital audio, half of the bits in each sample are allocated to the top decibel of loudness, just like half of the bits in each pixel of an RGB image are allocated to the top f-stop of brightness. So either the recording is compressed to make the most use of those bits, or a ton of fidelity is thrown away.

If you'd like to experiment with the results of this type of encoding, you can easily simulate an exaggerated version by opening a digital audio file in Audacity (or some other app), reducing its volume to 0.1% (or 0.01%, etc.) and then normalizing it. The sample quantization (and associated added noise) that results is the same thing.

I've heard of experimental systems based on logarithmic encoding, and I'm really not sure why they haven't caught on. The difference in processing difficulty must be negligible with today's technology.

Re:Sound Quality/Better speakers (1)

phantomfive (622387) | more than 5 years ago | (#25632265)

The problem with most of that type of person is that they refuse to participate in and/or accept the results of double-blind tests to see if they are perceiving something that's actually different or it's a psychological effect.

Give me a break, who are you even talking about? I'm not talking about mythical 'audiophiles' who are 'experts' and hear things no one else can hear, I'm talking about real differences in sound, that anyone who cares about can hear. If you want to hear it, I gave you an experiment you can do yourself to develop that ability. I am not imagining this.

I have wondered the same thing about audio encoding, and I think the reason is because anyone who cares uses 24 bit encoding, and really 16 bit encoding is nearly enough to represent the entire capability of any real-life speaker currently. It doesn't matter if there is more fidelity low range of the file format, because the speaker would be unable to do anything with it. Tweak [tweakheadz.com] has a good page talking about such things.

Re:Sound Quality/Better speakers (0)

Anonymous Coward | more than 5 years ago | (#25634011)

As a recording engineer with over 30 years experience, I have found the flaws are as follows. (In order of audibility).

The speakers.
The room the speaker are in.
The microphone.
16 bit 44.1Khz Digital recording.

"It doesn't matter if there is more fidelity low range of the file format, because the speaker would be unable to do anything with it"

This is entirely true, but no one will listen to you. An no one will even think of mentioning the room the speakers are in, which will often exhibit +-10dB nulls and resonances!

Re:Sound Quality/Better speakers (1)

blincoln (592401) | more than 5 years ago | (#25662559)

and really 16 bit encoding is nearly enough to represent the entire capability of any real-life speaker currently.

I think you are thinking of the Nyquist frequency, which is related to the sample rate and not the bit depth. Either way, you're right that 16-bit, 44KHz audio theoretically can represent anything that most speakers can reproduce, but I'm talking about something else.

The quality of the speaker doesn't have a whole lot to do with the quantization of the data encoding. Quieter audio (when recorded digitally) will sound worse than louder audio because fewer bits are being used to represent each sample. So when the digital data is converted back to analogue, its harmonics will be less like the original sound than if it had been recorded at a higher volume.

An extreme example would be a waveform recorded at such a low volume that the difference between the peak and trough is only one bit. When that digital data is converted back to analogue, the DAC is going to more or less smooth it out into a sine wave no matter what the original shape was.

Re:Sound Quality/Better speakers (1)

phantomfive (622387) | more than 5 years ago | (#25663555)

An extreme example would be a waveform recorded at such a low volume that the difference between the peak and trough is only one bit. When that digital data is converted back to analogue, the DAC is going to more or less smooth it out into a sine wave no matter what the original shape was.

Exactly. You said it much better than I have in this thread. But, the unfortunate thing is, even if the audio at that level weren't smoothed out to a sine wave by the DAC, the speaker would do the same thing at the physical level.

Re:Sound Quality/Better speakers (1)

MadKeithV (102058) | more than 5 years ago | (#25638091)

This means that in the case of digital audio, half of the bits in each sample are allocated to the top decibel of loudness

Each additional bit adds 6.02dB of dynamic range (http://en.wikipedia.org/wiki/Signal-to-noise_ratio#Fixed_point).
That's 6dB for one bit, not 1dB for half of the bits.

Re:Sound Quality/Better speakers (1)

blincoln (592401) | more than 5 years ago | (#25662433)

Sorry, maybe I worded my post badly - maybe I shouldn't have used the decibel unit? Or maybe the equations on Wikipedia give an "average" value (like the ones that tell you how much data can be stored in half a bit or whatever?).

There's a good explanation of the imaging equivalent of what I meant here: http://www.luminous-landscape.com/tutorials/expose-right.shtml [luminous-landscape.com]

Re:Sound Quality/Better speakers (1)

MadKeithV (102058) | more than 5 years ago | (#25673191)

What's important is how the sampling is done - in the case of PCM audio this is a linear sampling of the voltage of the input signal.
The "decibels" are relative to "full scale" i.e. maximum voltage. The actual power levels are linear. The "last bit" is a difference of 6dBFS with the "next bit".
I suspect that the sampling for imaging is rather different, and also as far as I know the human visual range is larger than can be captured with any one optical system. I am very wary of comparing the two unless I really research both, and I don't have time to do that :).
Still, it's a great discussion and it's teaching me a lot about audio and video sampling.

Re:Sound Quality/Better speakers (1)

Yoozer (1055188) | more than 5 years ago | (#25637725)

Now, however, carbon nanotubes might be the key to unlocking giant sound in your living room. Exciting times!

But that's not what I want. I want the sound piped directly into my brain, bypassing my ears - my brain goes up to 20khz without a problem, my ears don't anymore. Convolution reverb would allow you to add any "room" or ambience afterwards, plus you wouldn't be distracted by anything while listening to music - the perfect monitoring system.

Dick Tracey (1)

arizwebfoot (1228544) | more than 5 years ago | (#25629317)

Dick Tracey's TV/Phone watch is just around the corner at your nearest ________ store.

Imagine how this will help the medical community with diagnosis's. Send in the nanotube clowns and listen, watch, use sound to pound away at those nasty kidney and gall stones, etc.

Singing or speaking jackets? (2, Funny)

lumpenprole (114780) | more than 5 years ago | (#25629407)

As if ringtones weren't annoying enough. Welcome to hell.

Re:Singing or speaking jackets? (4, Funny)

pushing-robot (1037830) | more than 5 years ago | (#25629661)

There goes a man with his own theme music.

Re:Singing or speaking jackets? (0)

Anonymous Coward | more than 5 years ago | (#25630805)

"You know what the trouble about real life is? There's no danger music."

And he's never gonna' give(!) it(!) up(!) (1)

jonaskoelker (922170) | more than 5 years ago | (#25641135)

Imagine walking down the street being rick-rolled all the time. Or having to listen to 14-year-old girls' favorite boy band all the time. [the two may be identical]

On the other hand, imagine sneaking up on them from behind and tapping their shoulder while playing the imperial march and the hissing mask noise.

Or, better yet, the music from the murder scene from psycho.

Re:Singing or speaking jackets? (2, Funny)

pavon (30274) | more than 5 years ago | (#25631669)

And I thought my coworker wore loud shirts now.

Re:Singing or speaking jackets? (0)

Anonymous Coward | more than 5 years ago | (#25637191)

that's nothing in comparison to a ringing condom!

"oooh honey wait, I have to get this".

Waterproof, durable, flexible... (2, Interesting)

MadCow42 (243108) | more than 5 years ago | (#25629875)

To me it seems a natural fit to help "ruggedize" consumer electronics. One of the hardest things to seal on your phone is the speaker (and mic... which this probably wouldn't address in itself).

No more need for a speaker - just put the candybar up to your ear.

OT: Fixing /. displays? (2, Interesting)

Maury Markowitz (452832) | more than 5 years ago | (#25630035)

No matter what I try, certain articles are collapsed in the main-page view - including this one in Technology. Can someone tell me how to ensure that ALL articles are expanded?

Re:OT: Fixing /. displays? (1)

shot151 (1388155) | more than 5 years ago | (#25633485)

I have this issue as well...

Re:OT: Fixing /. displays? (1)

ZERO1ZERO (948669) | more than 5 years ago | (#25633789)

Slashdot front page has loads of display problems. The days of the couple mm left column overlap seem like the good times in comparison.

Re:OT: Fixing /. displays? (0)

Anonymous Coward | more than 5 years ago | (#25637183)

I think that's caused by voting, all the stories have +/- arrows and a small colored patch next to them, when the color isn't red, the story collapses presumably because it's unpopular.

The scale seems to work something like:

  • red - shown
  • yellow - collapsed
  • green
  • blue

Of course, I may be wrong though.

Re:OT: Fixing /. displays? (1)

pavon (30274) | more than 5 years ago | (#25654285)

Yes. Click on Help&Preferences on the top tool bar. First go to Index/General and uncheck "Use Beta Index", if it is checked and click save. Then go to Index/Sections and select which sections you would like to see on the index - the far right option is to always display the full summary.

The beta index has some nice features like voting, but currently ignores your settings when deciding which stories to collapse.

Bicycles (1)

sugarmotor (621907) | more than 5 years ago | (#25630331)

Should be good for playing music on bicycles!

Stephan

efficiency, frequency range (0)

Anonymous Coward | more than 5 years ago | (#25630413)

Nice use of nanotubes. Would be great to be able to replace cell-phone speakers with something new.
Anybody care to guess what kind of low frequency response these kind of speakers would have?
And what about power efficiency?

A nano-internet? (0)

Anonymous Coward | more than 5 years ago | (#25630461)

Chinese researchers have realised that a sheet of nanotubes behaves like a speaker when you send an audio current through it.

At first I read that as a series of nanotubes

Apple, jump on it (0)

Anonymous Coward | more than 5 years ago | (#25630483)

Apple please, jump on it and add it to your iPhone, so that at last my misconceptions about the first time I saw an iPod in a magazine in 2001 and thought the click wheel was an ultra-flat speaker can come true!

Those crafty Chinese (1)

robo45h (660508) | more than 5 years ago | (#25631049)

"Chinese researchers have realised that a sheet of nanotubes behaves like a speaker when you send an audio current through it. ...

None of that boring old electrical current for them.

No more earpieces? (0)

Anonymous Coward | more than 5 years ago | (#25631213)

Could this be an end to the ridiculous looking bluetooth earpieces people wear? Can they have them sewn onto their eardrums?

Who remembers... (0)

Anonymous Coward | more than 5 years ago | (#25631467)

the self-drying, speaking jacket in Back to the future II?

Re:Who remembers... (2, Funny)

boarder8925 (714555) | more than 5 years ago | (#25633237)

Who remembers the self-drying, speaking jacket in Back to the future II?

Come on, this is Slashdot, man. The right question is, who doesn't?

Endless Applications (1)

Serilleous (1400333) | more than 5 years ago | (#25632145)

One step closer to a nigh-untraceable Annoy-a-tron [thinkgeek.com]

Back to the Future. (1)

liquidMONKEY (749280) | more than 5 years ago | (#25636231)

The talking jackets statement reminded me of Michael J. Fox's 2015 in Back to the Future.

"Your jacket is now dry."
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