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Comment by dsr_ | Hacker News Reader

This appears to be describing an electrostatic speaker. They're on the market, and have been for decades, using mylar or a similar material.

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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.

Electrostatics shouldn't need magnets. The very name implies that; magnets have no appreciable effect on static charges.

Did you maybe mean transformers? IIRC electrostatics use rather high voltages.

You are correct. They do not use magnets but grids of stators. These grids of stators apply a good old fashioned electric field not a magnetic field. But the main difference remains, you still need two latge heavy things that take the sound signal and actually move the membrane.

There are no magnets in an electrostatic speaker. They are near-field quasi-static E-field actuators.

Cone+coil speakers are near-field quasi-static H-field actuators.

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.

They definitely look very different. I understand how ESLs work, but I don’t quite get how these move. Can anyone explain?

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.

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.

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.

Don't confuse magneplanar speakers with electrostatic speakers. Other than them both being flat they are quite different beasts.

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)

> Yeah I am really nonplussed

Well this tells me nothing.

(The two meanings of this word are essentially opposite)

The wrong meaning is the opposite of the right meaning

>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.

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

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.

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.

>"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?".

The commenter specifically used the word nonplussed in reference to the ranking of this post on the front page. The fact that their surprise and confusion stems from the promotion of unimpressive stories does not change the meaning from surprised and confused to unimpressed.

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.

Because it has nothing to do with EL speakers -- this is just the casual HN dismissal

I must have misread, but it seemed similar to me and would love an explanation?

They rather seem to be electrostriction speakers.

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?

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

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