Yes, recording techniques are not going to change. That fact also disables wide spread usage of multichannel in home audio reproduction.
Ambisonics is great for storing data. Only 4 channels (1st order Ambisonics) can store the whole sound field at the listening point. In Ambisonics the number of data channels is independent of the number of speakers used in reproduction. When reading pro recording and audio forums, one get's the impression that Ambisonics is much more common in recording and studio work than generally known. But practically no-one is using Ambisonics at home reproduction, though.
Obviously you haven't followed the discussion very closely, or by some reason are dismissing the fact that the side wall room reflections produced by the SSS are in great extend decorrelated compared to the real speakers. This is the reason for the increased spaciousness that conventional stereo is lacking. Another feature of this decorrelation is increased ASW. And still another feature is lack of speaker localisation, which could occur if real speakers were used.
So one cannot say side wall reflections and a real speaker therein are identical without any difference.
- Elias
Sorry but multichannel is in widespread usage.
It just didn't work for me, see http://www.diyaudio.com/forums/mult...-sound-single-loudspeaker-26.html#post2877529
I got better results by simply setting up two additional speakers at 60°. This increased ASW, which in combination with LEV forms "spaciousness".
It's also easier to control the amount of spaciousness with those two wide speakers. Increased ASW isn't appropriate for all types of content.
Power handling might also be slightly better than using smallish fullrange drivers. We also didn't talk about diffraction effects yet...
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I don't know anyone in person who's using multichannel for home audio.
Cannot argue about taste and personal preference.
I would say non existent ASW is not appropriate for most types of music. This is where conventional stereo fails, no ASW.
If I would need more power handling (which I don't at the moment for home use) I would propably try one of these
http://profesional.beyma.com/pdf/6CX200NdE.pdf
About diffraction.. That is exactly the reason I stated earlier of one possible explanation why your miniature proto failed. Too much of diffraction, no baffle gained directivity. The directivity pattern must be steered according the stereo panning. If the SSS speaker is totally an omni it does not work.
- Elias
Most likely the ideal is yet to be discovered.
In my current set up side panels are 40*33 cm. Other sizes could work too, as long as it is not too small.
If you would measure 360 deg horisontal directivity plot in stereo side panned signal condition of your miniature proto, you would propably find out the directivity steering is lacking in the midrange. That could explain your comment "everything is in the middle" because it acts mostly like mono omni.
- Elias
when TV is off I use it for background music in my living room too, and then, funny, people keep asking and asking where are the speakers?
You must stop teasing innocent people !
It may shock their habits on stereo triangle
I think it would work best with large side panels and side drivers located closer to the rear than the front. This would increase side directivity and lower the frequency of baffle step (where it becomes audible in front).
I would make the center panel as narrow as driver permits, unless greater enclosure volume is needed. The enclosure could be as tall as needed to provide interior volume.
Also would recommend either well-rounded corners or absorption on the faces to reduce diffraction off front corners of the enclosure.
This may not address every concern mentioned, but it should work better than incarnations to date.
-- Mark
After the first test, here is a normal and fearless evolution of the "SSS applied on a multi speaker group". Now the central speaker is also a five 12" array, curved baffle, same wiring, same drivers, but horizontal.
I will not enter in the details of the probable finger like lobes, but there is an happy consequence. In despite of the center element and of the matrix that for the common sense would reduce the stereo extension, there is a great increase of the maximal width. For the connoisseurs, this is not because the tweeters excite the reflections during some sharp transients. This comes only from the low mid bass. On some records, a double bass or a male choir can be projected at 60 degs on a side ( the base of the listening triangle is 5 meters and the listener is at 6 meters, it's not because of being the nose on the speakers). In some synthetic productions, this localization can even reach the 90 degs but this time with the help of the high frequencies.
Without the SSS, these extremes are each reduced of 30 degs.
Too wide is not realistic, I know, but this extra width happens for instance on some Haendel oratorios where it is said that the massive choirs are in the sides chapels of the cathedral, then it's not a fantasy but a better restitution.
God save the...Matrix !
I will not enter in the details of the probable finger like lobes, but there is an happy consequence. In despite of the center element and of the matrix that for the common sense would reduce the stereo extension, there is a great increase of the maximal width. For the connoisseurs, this is not because the tweeters excite the reflections during some sharp transients. This comes only from the low mid bass. On some records, a double bass or a male choir can be projected at 60 degs on a side ( the base of the listening triangle is 5 meters and the listener is at 6 meters, it's not because of being the nose on the speakers). In some synthetic productions, this localization can even reach the 90 degs but this time with the help of the high frequencies.
Without the SSS, these extremes are each reduced of 30 degs.
Too wide is not realistic, I know, but this extra width happens for instance on some Haendel oratorios where it is said that the massive choirs are in the sides chapels of the cathedral, then it's not a fantasy but a better restitution.
God save the...Matrix !
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Aside / OT -
Radugazon:
I think see something there (unrelated to SSS) I've tried too: Are those mass-loaded vinyl baffles? The curved feature of your arrays is as much happy accident as design . . . I too have done MLV baffles because I have access to a lot of it, and because it gives OB speakers a lot of design flexibility (pun intended
!). I've never posted about it for fear of a debate about a flexible baffle being 'wrong' (the answer: Baffle stiffness is completely moot if all resonance(s) fall below Fs of the system. With all those drivers on there, the system is inherently plenty heavy and well-damped).
I'm also going to try some baffles with recycled rubber mat, as it is more elastic and possibly better damped than MLV.
. . . It also smells good, like a new car.
And now, back to the SSS . . .
-- Mark
Interesting thread! I'm wondering, if one decides to buld such loudspeaker what would be the optimal/suggested implementation of this idea? What would be optimal dispersion characteristics of the speakers at each side? Is there any reason why only fullrange drivers have been used so far? Also what is the optimal bass arrangement? In other words how would you do it if you was to build the loudspeaker from the scratch? thanks!
keep up the good work
martin
keep up the good work
martin
Aside / OT -
Hi Tuba, I think Elias will not call the police, he's an open mind searcher and knows that all roads lead to Rome...
By the smell anecdote, I see that you are experienced. I use truck rear wheels mud guards, very soft rubber with a degree of elasticity, easy to make the holes, 4$ for a 75 x 50 cm plate (in Indonesia). It's also easy to secure them with some screws.
The thickness can be a matter of concern : too much it becomes rigid, too little it becomes almost acoustically transparent. I suppose that 5mm is a good compromise.
The hard structure is just an articulated ladder, I wanted to see what's the influence of concave vs convex (a waste of time and too wide driver inter spacing). Better to go directly to concave. BTW for a specific distance there is a shape that gives the best impulse and Hf extension.
The drivers are not secured hardly to the rubber plates, and not even to the ladder. They are suspended by nylon wires and the rubber dampens very nicely the drivers frames because it's really in forced contact, like a tyre on a wheel. The pictures can help to understand.
It can be considered as ugly and invading, as the ensemble is also suspended, but it's a very easy and fast way to make temporary experiments without hesitating to scrap everything in case of a new luminous idea .
Hi Tuba, I think Elias will not call the police, he's an open mind searcher and knows that all roads lead to Rome...
By the smell anecdote, I see that you are experienced. I use truck rear wheels mud guards, very soft rubber with a degree of elasticity, easy to make the holes, 4$ for a 75 x 50 cm plate (in Indonesia). It's also easy to secure them with some screws.
The thickness can be a matter of concern : too much it becomes rigid, too little it becomes almost acoustically transparent. I suppose that 5mm is a good compromise.
The hard structure is just an articulated ladder, I wanted to see what's the influence of concave vs convex (a waste of time and too wide driver inter spacing). Better to go directly to concave. BTW for a specific distance there is a shape that gives the best impulse and Hf extension.
The drivers are not secured hardly to the rubber plates, and not even to the ladder. They are suspended by nylon wires and the rubber dampens very nicely the drivers frames because it's really in forced contact, like a tyre on a wheel. The pictures can help to understand.
It can be considered as ugly and invading, as the ensemble is also suspended, but it's a very easy and fast way to make temporary experiments without hesitating to scrap everything in case of a new luminous idea .
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Currently my front panel is 20*40 cm. Side panels are 33*40 cm.
An externally hosted image should be here but it was not working when we last tested it.
Obviously the size of the element (directivity) is important as well as the size of the box.
There are two freq ranges where operation is different:
- at low freq it is based purely on vector steering due to the matrix
- at high freqs the vector steering become ambiguous due to very short wave length, ans so box dimensions and the baffle effect become critical. However the matrix still works at high freqs but it is based rather on 'power' steering than vector steering.
Once I tried 8" full ranges with SSSx5, but it sounded dull. Too much of beaming of the drivers.
So, I think side drivers should have wide dispersion, but not too wide because then they will leak directly to the front. However, the leaking is only a problem in the freq range where wavelength is too short for vector steering to operate but where the directivity of the element has not taken the control.
The ideal size of the box / drivers is ...
- Elias
The reason for full range elements at this point.. They are a good way to achieve exellent results fast and with moderate cost and design simplicity !
Other than that, they do provide useful characteristics like close to ideal vector summation from one point, and purposeful directivity if chosen right with the box dimensions.
The bass.. Currently I'm using normal stereo dipole bass with the SSSx5 crossed at 200 Hz. Of course the full ranges do not provide bass alone, have to add something there for support.
- Elias
Something I've been trying to work out in my head: If one wants to do a really minimalist full-spectrum SSS - using just 3 speakers and 2 channels of amplification, how do we deal with the bass?
I've got some bass-capable coaxes that I want to try SSS . . .
It seems that the L vs R level and phase shifts would make bass very challenging. 3 drivers won't play together well in a common bass enclosure. Creating a (non-matrixed) Lowpass and successful highpass into a matrix would get pretty complicated due to interaction thru the passive crossover region, etc.
Would everything work just fine if we make M = .33 in the bass range? , L-R bass is rarely very far out of phase on most recordings . . .
Waiting for a 'light bulb'
in my head to come on, -- Mark
Hi, I just noticed this thread, and am going through it. It's an interesting idea, and has me thinking. I haven't had a chance to read everything yet, but my impression is that the single speaker would have to be located in the ideal center of one's position in order to achieve stereo sound.
Unfortunately, speakers don't work well in the center of one's listening area be it near the walls or in the middle of the room. Its just not practical, especially if a TV is entered into the mix, or one has a wife. It simply will not make it beyond the 'spouse factor' IMO.
Anyway, I thought I would get myself established on this thread and receive notifications as it becomes active.
Unfortunately, speakers don't work well in the center of one's listening area be it near the walls or in the middle of the room. Its just not practical, especially if a TV is entered into the mix, or one has a wife. It simply will not make it beyond the 'spouse factor' IMO.
Anyway, I thought I would get myself established on this thread and receive notifications as it becomes active.
Hi, I just noticed this thread, and am going through it. It's an interesting idea, and has me thinking. I haven't had a chance to read everything yet, but my impression is that the single speaker would have to be located in the ideal center of one's position in order to achieve stereo sound.
Unfortunately, speakers don't work well in the center of one's listening area be it near the walls or in the middle of the room. Its just not practical, especially if a TV is entered into the mix, or one has a wife. It simply will not make it beyond the 'spouse factor' IMO.
Anyway, I thought I would get myself established on this thread and receive notifications as it becomes active.
What do you mean by "ideal center of one's position" ?
The location of SSs is not a problem, I have experimented placements in various configurations. It works when placed on the front wall and also 1 m from the front wall. I also succesfully placed it above a TV set.
- Elias