[HN Gopher] Classic components could be replaced by rubber in ne... ___________________________________________________________________ Classic components could be replaced by rubber in next-gen loudspeakers Author : crousto Score : 73 points Date : 2023-06-03 18:18 UTC (4 hours ago) (HTM) web link (www.polytechnique-insights.com) (TXT) w3m dump (www.polytechnique-insights.com) | _Microft wrote: | These speakers seem to work like this: | | There is a rubber layer, coated with conducting material to serve | as electrodes. The signal is applied in form of a high voltage | which makes the electrodes attract each other and contract the | rubber in between perpendicular to the surface (i.e. the rubber | layer gets thinner). Since the rubber material is relatively | incompressible though (volume of the material doesn't change), | the surface area of the membrane has to increase in return. To | generate sound from that, the membrane is stretched over a cavity | that is under higher than ambient pressure which helps expand the | 'balloon' when its surface area increases. This displaces | surrounding air which means the contraption is emitting | soundwaves. | | (I could only find a thumbnail of the first page of a paper from | that professor and extracted this from it) | | https://www.aes.org/e-lib/browse.cfm?elib=21108 | yummypaint wrote: | This sounds like an "electroactive polymer." there are some | squishy tapes made by 3m that incidentally have this property | out of the box. Make a spot of conductive carbon paint on each | side, apply a few kV, and watch the spots double in area as the | electrostatic forces squish the material. | sandreas wrote: | If you want an affordable, good sounding speaker that you can | build yourself, you might wanna take a look at Tech Ingredients: | | https://www.youtube.com/watch?v=CKIye4RZ-5k | Kapura wrote: | The article mentions the fragility, but seems extremely | optimistic on the ability to solve this, but I'm not sure way. It | just says "once this is overcome" but the things it seems to be | talking about are major barriers to a commercial product. | smnscu wrote: | [flagged] | KennyBlanken wrote: | > I had ChatGPT expand on the paragraphs | | Yeah, don't do that. Nobody wants to read "AI" textspam here in | the comments. | | > so take the audiophile considerations with a grain of salt | lol. | | The understatement of the year. Repeat after me: chatgpt is not | deterministic. | kennywinker wrote: | Just to +1 this, in general nobody wants to read AI textspam | anywhere. I hope the trend is over now but like a month ago | any time somebody would ask a question on the slack I'm on, | someone else would copy-paste 500 words of chatgpt blathering | with a similar "disclaimer". | | We all know about chatgpt now. If someone wants a chatgpt | answer to their questions, they can go get that themselves. | dsr_ wrote: | This appears to be describing an electrostatic speaker. They're | on the market, and have been for decades, using mylar or a | similar material. | vr46 wrote: | I was wondering much the same, except I note that my pal's | massive Quads and the older radiator-like versions at uni were | still crazy heavy due to the power supply (I assume) and they | were a bit short on warm bass, perhaps these "new" speakers run | on a trickle of power and produce bass like a Cerwin-Vega for | all I know? | ilyt wrote: | The power supply problem is not power but voltage, | electrostatic speakers just require high voltage | | Also they are expensive audiophile thing so good chance they | were driven off some super inefficient and/or made on | discrete componentes, hence the size | hristov wrote: | It doesn't. This scheme uses a membrane like the electrostatic | speakers, but otherwise it is quite different. In the | electrostatic speakers, you load the membrane with extra | electrons and then use electro-magnets to apply a varying | electric field across the membrane in accordance with your | sound signal. Since the membrane has much more electrons than | protons, the electric field causes the membrane to move. This | method requires magnets. | | The system in the article does not use magnets. What they do is | they make a membrane that moves when a voltage is applied | between its top and bottom surfaces. Thus, the membrane can | probably be referred to as being piezoelectric, although the | article does not use that term. In this case you can apply the | sound signal directly to the membrane and make it move, and | when it moves it creates sound. Thus, this system does not | require any magnets. | | The lack of magnets will make it much lighter. Also, the fact | that you are applying the signal directly to the thing making | the sound may result in better sound quality. | buildbot wrote: | Yeah I am really nonplussed how this is the top post on HN | right now (I know that is against the rules to mention but | really) | ahahahahah wrote: | This is the response of someone who knows that electrostatic | speakers are a thing and has seen marketing or other images | of them, but has no idea how they work and lacks either the | curiosity or the capability to learn. The speakers described | in this article are nothing close to electrostatic speakers. | coldtea wrote: | Because it has nothing to do with EL speakers -- this is just | the casual HN dismissal | TulliusCicero wrote: | > Yeah I am really nonplussed | | Well this tells me nothing. | | (The two meanings of this word are essentially opposite) | CrampusDestrus wrote: | The wrong meaning is the opposite of the right meaning | samstave wrote: | > _Well this tells me nothing._ | | Well its certainaly not a non negative statement because | its talking about being plussed, which is a positive | statement, so a nonplussed person is truly chaotic-neutral. | falcolas wrote: | I can't tell if serious or sarcastic. Either way, here you | go. | | nonplussed : adjective | | - Bewildered; unsure how to respond or act. | | - Unfazed, unaffected, or unimpressed. | | - filled with bewilderment | flyingcircus3 wrote: | This meets the criteria of Poe's law. It is equally | reasonable to assume _you_ are being sarcastic or | serious. If they didn't just recently look up the | definition themselves, they wouldn't have commented about | the conflict in the two definitions. | flyingcircus3 wrote: | Summarizing dictionary.com: | | 1. Surprised and confused 2. Unperturbed | | "Yeah I am really unperturbed" doesn't make sense in | context of it's parent. | | I'm not sure how you could be nonplussed about this. | coldtea wrote: | > _" Yeah I am really unperturbed" doesn't make sense in | context of it's parent_ | | It's not just unpertrubed, it's also "not impressed". | | In the context of the comment it basically means "I see | this speaker announcement as nothing special, what's the | big deal?". | dist-epoch wrote: | I'm not so sure. Electrostatic speakers have big heavy metal | electrodes. | | They talk about a thin conducting layer on the rubber, quite a | different thing. | aidos wrote: | They definitely look very different. I understand how ESLs | work, but I don't quite get how these move. Can anyone | explain? | falcolas wrote: | As I understand it, the rubber being is forced into the | shape of a dome via air pressure, which makes one side a | bit bigger than the other. The electrostatic charge on the | opposing faces when one is bigger than the other would | cause it to flex - acting as a speaker diaphragm. | | It's a bit of a guess though; its definitely outside my | wheelhouse. | karmakaze wrote: | Like an electrostatic speaker the opposite charges' | attraction generate movement. The difference is in an ESL | one of the charges are stationary. In this new scheme, both | charges are on the membrane but on opposite sides where | attraction compresses/thins the rubber causing it to expand | along its planar directions causing the dome to get larger. | The inner air pressure is to assist the expansion movement. | chrisdhoover wrote: | Magnepan speakers have been around since the 1970s. They do | not have anything heavy. Martin Logan speakers do have a | heavy base presumably the driver. | jakedata wrote: | Don't confuse magneplanar speakers with electrostatic | speakers. Other than them both being flat they are quite | different beasts. | buildbot wrote: | This seems only mildly different than already existing | electrostatic drivers??? In terms of getting rid of heavy magnets | at least. | jeffbee wrote: | Yes, as we know from the history of electrostatic speakers, all | you need to replace those bulky magnets is a sheet of mylar the | size of a billboard, and also a regular magnetic voice coil for | the half of the power spectrum that they can't handle. | buildbot wrote: | These seen smaller than a billboard: https://www.crutchfield. | com/S-Me16Db11xTX/p_839EMESLD/Martin... | | And with lower frequency sound, aren't heavy drivers actually | better? You literally need more mass/energy to push more air, | but at a lot lower frequency so the effect of moving the mass | back and forth at 20Hz does not really matter as much as | 40Khz? | bob1029 wrote: | The weight of the driver is not really a factor so much as | a side effect of the engineering. You want to look at it in | terms of total volume displaced and the sensitivity (if you | are thinking about efficiency). Drivers with more surface | area & excursion typically do have larger magnets and | support structures. | | LFE reproduction is all about moving large volumes of air | by any means necessary. There are relatively featherweight | subwoofers that literally use fans to move volumes of air | and achieve performance that is impossible in traditional | drivers of any weight class. | | Doesn't really matter how you do it as long as things stay | in phase. | ilyt wrote: | > These seen smaller than a billboard: https://www.crutchfi | eld.com/S-Me16Db11xTX/p_839EMESLD/Martin... | | Right... because this one contains a normal magnetic woofer | Puts wrote: | Wouldn't rubber dry out over time? If you pay for a good set of | speakers you probably want them to last for decades. | coldtea wrote: | Couldn't you just replace it? We also pay for good cars, but we | still change their tires every so often... | sublinear wrote: | > Current loudspeakers use a magnet coupled with the movement of | a copper coil to vibrate a membrane. In the future these heavy, | bulky, and expensive components could be replaced by a dielectric | elastomer membrane. | | They mention efficiency, but not power. I don't like how this is | framed as the general future of all speakers when it's really | just the future of midrange drivers. | tapper wrote: | My screen readers reads that site in a verry strange way. It says | that there is soft hyfens in a lot of the words so it reads the | words like reproduce as"repro duce" | gtvwill wrote: | Ehhhh interesting, might go well for tweeters. Can't see it being | great for bass. Can't be arranged in a paraflex horn config. ___________________________________________________________________ (page generated 2023-06-03 23:00 UTC)