Paul.
Well-known member
This is a fun yet slightly biased and gushing summation of Tesla's works...
http://theoatmeal.com/comics/tesla
http://theoatmeal.com/comics/tesla
The_Lhc said:hammill said:steve_1979 said:oldric_naubhoff said:... another example is Tesla's invention. if it wasn't for steel manufacturer's lobbying we would be using wireless electricity long by now...
Erm. What?
http://en.wikipedia.org/wiki/Wireless_energy_transfer
I think he meant the bit about the steel manufacturers lobbying, that isn't mentioned in that Wiki-article.
interesting indeed but the designers will get 0% for aesthetics! unless they incorporate the concept into an existing design....perhapsoldric_naubhoff said:ok. people who know a little my attitude to hi-fi know that I'm no too much fond of box speakers with dynamic drivers. this is not some illogical, emotionally driven, "just because" kind of way hatred. as I was gaining more and more knowledge on how it all works together I came to conclusion that in order to reach my audio nirvana I have to try out other available technologies of sound reproduction. and since speakers are traditionally "the weakest link" I believe the search and research is a worthwhile endeavour. so, I couple of days ago I stumbled upon this thing here:
this rectangular steel frame doesn't look much like a speaker but it is a speaker nonetheless. it resembles nothing that's been invented so far. quite rightly so, it's not working like anything invented so far. I confess that I read the whole part describing how it works and still can't quite comprehend how it actually can reproduce music! I can acknowledge it can make some sounds on its own, but reproduce recorded sounds? but apparently it make quite good job. in fact, if it's as good as it's claimed on the web site this thing may be a bigger step in quality of reproducing music than Western Electric cinema horns from ca. 1930 were over phonograph's sound tube (note that those WE speakers can easily compete with modern designs in terms of SQ)!
there's not much details about its performance know to me yet, but they do attach freq response and phase graph on their web site. I wish they had some more usual speaker performance measurements in order to draw any meaningful conclusions. but this measurement alone inspires some optimism:
freq response from 20 to 20K Hz is simply put flat. and it's flat in good amps' performance terms, not good speakers terms. also there's essentially no phase shift from around 100 Hz to 10K Hz. and even phase shift for the full spectrum is still commendably low compared to most multiway speaker designs. this is always a good sign for perfect spacial resolution - i.e. imaging.
what's the list of strengths? here goes:
- this is a true full range speaker, so no need for any detrimental crossovers networks
- true omnidirectional principle for truer spacial reproduction (no need to spend $$$$$$$ for MBL omins any more)
- no box, so no box colouration nor any box reflections nor any baffle related freq response irregularities
- inherent phase coherence, as noted above an asset for better imaging
- the driver is incomparably stiffer compared to other materials drivers are made of (well it's essentially a steel rod with triangle cross section) so no problems traditionally related with finite driver stiffness like break-up modes or non-linearities at high x-max. this should translate to very good THD performance but let's wait for proofs.
cons? none. well, maybe, for some, the looks. but it's only the prototype so production version may look more WAF friendly.
I encourage you to take a look at the web site (I left the link at the top of the post). and if you don't fancy reading through all that techy flavoured blurb read testimonials at least. very interesting reading indeed...
busb said:Think of a Wankel engine rather than one with pistons! It's design is very simple. The triangular vertical omni-directional radiator doesn't rotate but oscillates or pivots around its vertical axis - a fixed magnet provides centring for the radiator at rest & magnetic damping at its resonant frequency. The angular displacement is proportional to input amplitude. The mass of the spindle would need to be almost zero & very stiff so that tortional forces don't cause phase errors from one end of the radiator to the other that would be frequency dependant.
busb said:Maybe not a hoax but I can't see it being flat in frequency nor very loud.
busb said:I'm also not sure if a 360 degree omni-directional source is a great idea in a room with reflecting surfaces such as walls.
Sliced Bread said:It looks fascinating, though do you recon you'd get phase issues having an open source vibrating? (more a question than an opinion)
Sliced Bread said:I'm guessing this is just a concept at this stage. Hopefully it could be installed quite discreatly (assuming it works well).
oldric_naubhoff said:busb said:Think of a Wankel engine rather than one with pistons! It's design is very simple. The triangular vertical omni-directional radiator doesn't rotate but oscillates or pivots around its vertical axis - a fixed magnet provides centring for the radiator at rest & magnetic damping at its resonant frequency. The angular displacement is proportional to input amplitude. The mass of the spindle would need to be almost zero & very stiff so that tortional forces don't cause phase errors from one end of the radiator to the other that would be frequency dependant.
thanks for explanation.
busb said:Maybe not a hoax but I can't see it being flat in frequency nor very loud.
that's what I'm affraid too.
busb said:I'm also not sure if a 360 degree omni-directional source is a great idea in a room with reflecting surfaces such as walls.
I don't think it's a problem. contrary, I think that's an asset. i have never heard anything bad about MBL's omnis so far (I wish I could listen to what their Radialstrahlers can do one day) and usually they get best sound of the show accolades, wherever they appear.
I think that lobing artefacts are a bigger evil in case of multidriver systems with poor dispersion characteristics. and that's where wall reflections will not contribute anything good.
those Planot speakers seem to work like line source so they should radiate steady wave of sound over the length of the driver into the room. and that means possibly less lobing and definitely less floor and ceiling reflections.
oldric_naubhoff said:... another example is Tesla's invention. if it wasn't for steel manufacturer's lobbying we would be using wireless electricity long by now...
Paul Hobbs said:This is a fun yet slightly biased and gushing summation of Tesla's works...
http://theoatmeal.com/comics/tesla
OneBoxSystem said:See http://www.planotspeaker.com/Planot/Home.html
OneBoxSystem said:See http://www.planotspeaker.com/Planot/Home.html
Planot said:I am the inventor of the Planot loudspeaker driver; more specifically a new class of acoustic transducers.
I would welcome questions. I will answer then as best as I can.
John
Planot said:I am the inventor of the Planot loudspeaker driver; more specifically a new class of acoustic transducers.
I would welcome questions. I will answer then as best as I can.
John
Planot said:The efficiency of the current prototype is not high. Future prototypes will have higher efficiency. The motor is a limiting factor and magnet strength is critical; it is expensive to have custom magnets made. China has been artificially raising the price and availability of the rare earth metals used in exotic magnets.
Planot said:Specifications and measurements will not mean a whole lot in the scheme of things because different manufactures will implement my diaphragm design, differently. Each engineer has his own idea of the best way of achieving a design goal. So as far as the public is concerned wait for real consumer and professional products to appear before being too concerned over measurements.
Planot said:The current potor "voice coil" has a 4 ohm rating.
Planot said:Yes, it occilates