9.1, 11.1, 13.1 (or .2)

[Colin Dunn]

I'm curious about some of the developments with home theater receivers offering up to 13.2 channels:

9.1 = 7.1 + front-height
11.1 = 9.1 + front-width
13.1 = 11.1 + rear-height

I haven't seen anything about updates to Blu-ray to produce a discrete signal above 7.1. So "height" and "width" has to be derived through a matrix decoder approach. Much has been written about out-of-phase information in stereo recordings being recovered into surround channels, but how do you get "height" or "width" out of 7.1 to derive between 9-13 channels?

It also seems that only mini-monitor type speakers would be practical if you need to fit 13.2 channels into a listening room! Planar fans like myself may never get beyond 7.1 due to the space and amplifier power those things take.

 

[proufo]

It also seems that only mini-monitor type speakers would be practical if you need to fit 13.2 channels into a listening room! Planar fans like myself may never get beyond 7.1 due to the space and amplifier power those things take.

Other than the front three speakers, the rest are "effect" speakers that, in general, are cheaper and smaller than the LCR ones.

Of course you'll need five main speakers for modern multichannel audio (except the ambiance kind, akin to movie surround).

 

[leevitalone1]

The extra channels are great in theaters, but home? admit I never heard 7.1 but 5.1 or 5.2 is plenty enough. I think speaker makers invented anything over 5.1 anyway. Most movies are max 7.1, music? 5.1, enough.

 

[ssully]

Tomlinson Holman, who should know, says 10.2 is the way to go. I would not doubt him.

 

[zabble]

I'm sure that 10.2 has the potential to sound amazing. However, with record labels only trickling out 5.1 releases as it is now, how many titles can we expect to be issued newly mixed in twice as many channels? That and the fact that the end users will have to buy six more speakers, six more channels of amplification and a new player seems to be a recipe for format failure right from the start.

I'm not trying to be pessimistic, only realistic. I'm perfectly content with 5.1.

 

[proufo]

I'm sure that 10.2 has the potential to sound amazing. However, with record labels only trickling out 5.1 releases as it is now, how many titles can we expect to be issued newly mixed in twice as many channels?

Ambiance channels can be derived from the source channels.

Sadly, that approach hasn't been followed much for music beyond 7.1, except for one or two ultra-expensive ($20k) processors. Audissey is expressly for movies.

 

[proufo]

Tomlinson Holman, who should know, says 10.2 is the way to go. I would not doubt him.

Let's hope he's working on music systems at Apple, not just home theater.

 

[Colin Dunn]

The closest thing to Tomlinson Holman's proposal is 11.1(2).

Audyssey DSX synthesizes 11.x from a 5.1 or 7.1 source, adding front-height and front-width speakers: http://www.audyssey.com/technologies/dsx

Looks like the idea of going beyond two surround back channels is falling out of favor, due to psychoacoustic research that indicates human hearing is more sensitive to placement within the front hemisphere. In fact, 10.2 goes back to a single rear-surround channel, much like 6.1.

But what I'm curious about is - how is "height" information extracted using matrix-type techniques? I could see width as looking at sounds with extreme separation in the front stereo pair; that makes more sense as being possible to derive from a stereo or 5.1/7.1 signal.

 

[proufo]

Some may find this interesting:

Yamaha - Method and device for improved sound field rendering accuracy within a preferred listening area

"The Invention relates to a method and a device for sound field reproduction from a first audio input signal using a plurality of loudspeakers aiming at synthesizing a sound field within a preferred listening area in which none of the loudspeakers are located, said sound field being described as emanating from a virtual source, said method comprising steps of calculating positioning filters using virtual source description data and loudspeaker description data according to a sound field reproduction technique which is derived from a surface integral, and applying positioning filter coefficients to filter the first audio input signal to form second audio input signals".

 

[britmarc]

NHK here in Japan were talking about 22.2 surround for their 'Ultra-HiVision' / ultra HD system....