This goes onto the list of awesome Graphene things I'll likely have to wait for for some time, along with:
Graphene Supercapacitors [<a href="http://www.kcet.org/news/rewire/science/more-good-news-on-those-carbon-supercapacitors.html" rel="nofollow">http://www.kcet.org/news/rewire/science/more-good-news-on-th...</a>]
Graphene Antennas [<a href="http://bgr.com/2013/03/06/graphene-antenna-research-terabit-361954/" rel="nofollow">http://bgr.com/2013/03/06/graphene-antenna-research-terabit-...</a>]
and other things I'm most likely missing here. But seriously, the technological possibilities of this stuff baffle me. Hopefully they become the next light emitting diode (in terms of price, availability, flexibility and output compared to previous technology).
I should note that the Sennheiser MX400 headphones in question are a $10 unit. Definitely not the worst you can get for the price, but by no means high-end units. Just something to keep in mind when thinking about this.
Here is a frequency response graph for a pair of HD800s which are sennheiser's top of the line head phones<p><a href="http://cdn.head-fi.org/4/43/43663901_HD800graph.jpeg" rel="nofollow">http://cdn.head-fi.org/4/43/43663901_HD800graph.jpeg</a>
Good on the original article to show the "Vdc" bias voltage (battery symbol) required to charge the diaphragm relative to the surrounding electrodes, and to show (conceptually) an inverting unity gain amplifier for one electrode of the signal ("Vin") so that balanced (opposing) electric signals drive opposing sides of the diaphragm.<p>Without the bias voltage, there would be no electric bias field between either electrode relative to the diaphragm, against which bias fields the signal adds or subtracts in order to move the diaphragm bidirectionally.<p>The required bias voltage of an electric field headphone element (or speaker) is very much akin to the permanent magnet of a conventional electromagnetic loudspeaker -- both provide a fixed field against which the signal works to produce proportionate mechanical motion.<p>Whether this bias voltage requirement will eventually result in "phantom power"[1] on analog "headphone outputs" as it has [optionally] for professional analog microphone inputs[1] -- or small power cells and inverting electronics in the headphones or on the headphone wires (perhaps supporting other analog or DSP functions such as active noise cancellation, equalization for flatter response, or decryption of an encrypted digital headphone signal) -- may be up for the market's consideration in a few years.<p>[1] <a href="https://en.wikipedia.org/wiki/Phantom_power" rel="nofollow">https://en.wikipedia.org/wiki/Phantom_power</a>
That response is far from "superb"! If I'm reading the scale right, there's a 30+dB difference between 200Hz and 20kHz. The article explains how a "flat" frequency response is the ideal target, then claims that a graph that is <i>anything but</i> flat is "superb"?
Earphones, or rather speakers, are fascinating things. How simple they are in comparison to the many technological leaps necessary to recreate visual input.<p>(We still don't have decent displays; all of them are flat, and most of them look terrible)
i don't have the greatest understanding of how speakers work, so correct me if i'm wrong, but wouldn't an increase in energy efficiency (making the speakers easier to drive) mean that for the same volume level on a source, the graphene speaker be louder?
i sometimes find that at lowest level my headphones can be a bit to loud in some quiet environments, so graphene headphones would be even worse