That's right. But like "realism" or "natural", "spacious" is a highly subjective term, which means very different things to different people. For someone it is simply immersion (sound from everywhere), which can be had perfectly even in the bathroom. For another one spaciousness is the decay of an organ sound, literally crawling down the aisles of a big church for seconds - which is almost impossible to reproduce in a small room.
The word "omnipolar" is as arbitrarily used in this discussion. I could easily build dipoles which are more omnipolar in the upper decade of their power response than the Pluto. And listening to "real" omnipolar speakers from a short distance against an highly absorbing front wall will make no practical difference compared to more directive speakers.
It is this uncertainty of terms which makes this discussion rather fruitless, imho.
I agree with your comments Rudolf. In case we need definitions, this paper might be interesting..
http://www.icad.org/websiteV2.0/Conferences/ICAD2002/proceedings/Morimoto1.pdf
http://www.icad.org/websiteV2.0/Conferences/ICAD2002/proceedings/Morimoto1.pdf
Nice logical mod to the Pluto to add a rear FR driver. I guess this rear driver on the Pluto would qualify it as a true omnipole for the entire frequency range, at par with the new LX521.
I find the spacing b/w the 2 FR drivers quite large, likely 8". Did you wire them out of phase to simulate dipole radiation to prevent early sidewall reflections or wired in phase like a bipole...in which case how did you mitigate the bipole dip without any real "wide" baffle separating the 2 FR drivers.
Most importantly, does the addition of this second 2" FR driver to the Pluto, make it sound better ??
Thanks.
But still you should build it acoustically small and avoid diffractionahh, like low mounted drivers tilted 45degr
In general I would suggest that people, who want to try omnis check if their room (e.g. placement and listening distance) can cater for them and then let them judge themselves.
I'd say the reverse, my omnis sound basically the same independent of where in the room I put them or where I listen. Assymetric listening positions where I'm closer to one of the speakers isn't a problem either except for the volume difference.
for my part and from my experience I have to say that OllBoll is 100% right
perhaps the devil is in a detail and sth is wrong with some "omnis" or some rooms are too live (which affects clarity with "omnis") or too asymmetrical in themselves
I say "omnis" because we all know that we are not talking about real omni directional characteristics which in fact are not desirable at all
In case we need definitions, this paper is of limited use. The paper describes primary source emulated by speaker in large spaces, perhaps via anechoic chamber. It describes Auditory Source With, ASW in terms of small source width being perceived as wider due to lateral reflections. The author lumps reflections from 20ms-80ms as early reflections, completely ignoring directional processing that occur in <3ms range.
Aurthor suggest a basic grasp of underlying principles:
But goes off and gets confusing language and symbol assignment into play: What is difference of
"ΔLsp" and "ΔLasw", taken from these two lines:
So author is he saying more lateral reflections improve source width, and more reflections in general improve envelopment?
Regards,
Andrew
Aurthor suggest a basic grasp of underlying principles:
But goes off and gets confusing language and symbol assignment into play: What is difference of
"ΔLsp" and "ΔLasw", taken from these two lines:
So author is he saying more lateral reflections improve source width, and more reflections in general improve envelopment?
Regards,
Andrew
Andrew, that Morimoto is a knowledgeable guy, he was president for the Japanese Acoustical Society and has done acoustical research for 30y at a high level, not really a beginner..
The reason for posting the paper was to help in a definition for "spaciousness" which is clearly made of two components and yes, <80ms for music qualifies as early reflexions, as still in the limit of the precedence effect.. nothing new there.
Reading it one realizes how difficult it is to get true envelopment from small rooms, as 80ms relates to a 25m+ sound path. Wouldn't an active solution on a dead wall work better?
The reason for posting the paper was to help in a definition for "spaciousness" which is clearly made of two components and yes, <80ms for music qualifies as early reflexions, as still in the limit of the precedence effect.. nothing new there.
Reading it one realizes how difficult it is to get true envelopment from small rooms, as 80ms relates to a 25m+ sound path. Wouldn't an active solution on a dead wall work better?
yes, multichannel, be it 5/7.1 or matrix decoded from stereo. The problem is you can easily end up with a sort of "reverb coating" that sounds the same on every recording, or just plain wrong because you still get early cues and spectral density that signs the room as "small" for the brain. Going from 2 til 4 surrounds didn't bring more for me, and 80ms delay was way too much but it was a very flimsy and cheap setup I admit.
It's definitely a very interesting venue to pursue. Will surely keep me busy for the winter!
It's definitely a very interesting venue to pursue. Will surely keep me busy for the winter!
I don't see a definition for "spaciousness" in psychoacoustics. Toole and others "explain" it as a summation of ASW, LEV and IAAC. All three are surely parts of "spaciousness", but isn't the common understanding of spaciousness much wider?
lolo, thanks for the Morimoto link.
It took me a while to absorb it. But no, I can't follow your "help in a definition for "spaciousness" which is clearly made of two components". To me it is like defining "car" as "four wheels driven by an engine". Makes sense, but is only scratching the surface of the real thing.
Rudolf
The common understanding is wider without the understanding, yes
Spaciousness is ASW and LEV.
Best sounding omni I've heard is the B&O with the S.A.W. lens:
An externally hosted image should be here but it was not working when we last tested it.
If you don't want to build a lens, there were some speakers at the 2012 CES that use a similar arrangement, but without the lens.
I can dig up the URL if you want, don't remember the name offhand. The patent on the latter speakers cites the former, so they're clearly 'inspired' by the B&O
Another easy way to do an omnipolar speaker is to take four of the JBL Control Now speakers and set them up in a 'donut'
I have some threads with measurements and commentary on those speakers also
The common understanding is wider without the understanding, yes
Tsk, tsk..
I'm going to have to give you a citation for using an ACOUSTIC term in a REPRODUCTION context. 
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