The other thing I noticed in the video where the designer is describing the speaker is that he's saying "each driver handles only a narrow frequency band", which leads me to believe it's just a bunch of bandpass filters. He also keeps talking about reproducing "harmonics", which makes me wonder if he really know what he's talking about. A music track contains myriads of harmonics and most likely non-harmonic frequencies as well from noise (as in cymbals and similar), as well as beat frequencies arising from non-linear combination of sounds. Reality is highly non-linear...
The designer started this thread
https://www.audiosciencereview.com/...st-speaker-to-reproduce-a-60hz-sq-wave.50863/
also look here https://www.diyaudio.com/community/threads/ultimate-open-baffle-gallery.123512/page-232#post-7988607
https://www.audiosciencereview.com/...st-speaker-to-reproduce-a-60hz-sq-wave.50863/
also look here https://www.diyaudio.com/community/threads/ultimate-open-baffle-gallery.123512/page-232#post-7988607
Nothing instills confidence like when someone talk about a "sign wave"...The designer started this thread
That is true for a single extended source. But that is not the case in this case. Each frequency range has its own (single) point source.imaging details suffer almost inversely proportional with the individual point source separation distance.
The bandwidth of each loudspeaker array in this case is divided into 20 point sources, each a different distance from the reference listening tuning position.But that is not the case in this case. Each frequency range has its own (single) point source.
The FIR processing can time and phase align each of the 40 initial direct wavefronts at one specific listening position, the stereo image "picture" can be "in focus" there.Stereo format works only in the horizontal plane, and the speakers (sound sources) are located vertically, how should this affect the detail of images in the stereo picture?
The high frequency elements are not vertically located over the lower bands, and the individual dipole radiation patterns of the various frequency bands are widely separated vertically, decreasing correlation of any room reflections to the virtual single point source alignment position.
The term 'Fourier' is definitely a misnomer. To Fourier transform t seconds of an audio signal of with a bandwidth of B hertz, one would require t.B/2 different sources. e.g. 1 sec waveform 10 kHz wide would require 5000 distinct sources, each programmed to produce a signal of given amplitude and phase, and each updated every second.
Its an extreme multiway speaker.
In concept, it does vaguely remind me of the Melotron (any Moody Blues fans out there?) and the Moog synthesiser.
Its an extreme multiway speaker.
In concept, it does vaguely remind me of the Melotron (any Moody Blues fans out there?) and the Moog synthesiser.
Just one sweet spot then.The FIR processing can time and phase align each of the 40 initial direct wavefronts at one specific listening position, the stereo image "picture" can be "in focus" there.
SO it is a 25-way speaker with each way operating in a extremely narrow band?After all is said and done, I believe the system basically behaves as a collection of crossovers.....i.e., a very complex multi-way speaker system.
But the frequencies are spread all over the place, spatially speaking. And the inherent non-linearity of each driver will still be present. There probably would be less intermodulation distortion. But imaging? That's a hard sell.
Once in the digital domain there might be some gains to be had by pre-distorting the signals fed to each driver so their output contains LESS distortion but that would require some pretty good characterization of each driver. Particularly since the distortion could vary with temperature and drive level.....
It's interesting but I think it is impractical......a whole lot of work and money for relatively little improvement in audio quality, if any. It sure looks cool though.
Yup. And I wonder if that’s really such a great idea. A perfect crossover doesn’t exist. You’re always going to have both amplitude and phase non-linearities in the crossover region. Now you have 24 of those regions. I’m just a lowly immigrant from Sweden, so what do I know, but it doesn’t feel like it would warrant the no doubt astronomical cost for such a speaker…SO it is a 25-way speaker with each way operating in an extremely narrow band?
Well, 20 way.SO it is a 25-way speaker with each way operating in a extremely narrow band?
This explains the use of DSP heavily. Time Alignment, crossover, etc... Approximately, what is the bandwidth of each driver or set of drivers?
Approximately 10 octaves divided per 20 is half an octave (on octave covers eg. 160-320Hz)
The basic issue with the loudspeaker is IMO, that the designer doesn't seem to undertand acoustic radiation challenges of loudspeakers
The basic issue with the loudspeaker is IMO, that the designer doesn't seem to undertand acoustic radiation challenges of loudspeakers
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