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Single Speaker Unit Delivers Surround Sound
Makarand writes "A one-speaker home theater system that is able to deliver surround sound
has been unveiled by Nirotek America (Torrance, CA).
The single speaker unit actually contains five individual speakers packed
horizontally into a single case. The surround sound effect is achieved
by playing some sophisticated psychoacoustic trickery on the human brain.
Realistic surround sound from movies and stereo CDs can be obtained as long as listeners
are
at least six feet away from the speaker unit and the unit stands near the front edge of
whatever surface it is placed on. The unit is priced at around $799 and USA Today has a
review."
However, you'd have to have fairly long arms to work a handheld gaming device that must be a minumum of six feet away, wouldn't you?
I'm surprised no one ever seems to mention the binarual method of recording and playback when it comes to surround sound.
The main techniques used by humans to locate the direction of sound are: the volume of the sound, the phase difference between the sound hitting each ear at slighlty different times and the effect that the head, ears, body have on altering the frequency makeup of the sound.
The way to recreate this is to use a dummy head with miniature microphones placed in each ear of the dummy to record whatever sounds you want and then to play that recording back over headphones.
The dummy head recreates all the subtle phase and frequency effects that a real human head would in the real environment and the headphones allow that recording to be delivered to each ear free of the distorting effects that loudspeakers are prone to have(room effects, cross channel problems, phase problems etc).
Checkout http://www.binaural.com/ for MP3 samples of this technique.
The realism of binaural is simply staggering when used with the right headphones. No multi-channel surround sound that I have ever heard comes anywhere near close. It is so realistic that it can have you looking around to locate the source of the sound to make sure it wasn't really something in your immediate environment. The problem is that most people don't want to wear headphones when watching movies I suppose.
Yeah, and what's sad is a lot of audio rags promoted these snake oil products, claiming there was a noticeable difference. I once did a comparison between using a thick cable, a thin cable and UTP cable (!) to my speakers, and I found no difference. Perhaps there was a small difference in sound quality, but I couldn't hear it, and Joe Sixpack probably wouldn't notice either. Probably because, like many people, I was using relatively low power, a mediocre amp and mediocre speakers. I cancelled my subscription to some audiophile magazine when they tried to pull the same crap with [fiber]optical connections, claiming that a bad cable would "reduce the dynamic range of your sound". While I can understand the problems caused by a bad digital link-up, I think I would describe it as "abrupt end of data stream and therefore a lack of sound." A bad optical connection would immediately be obvious.
Many suround sound systems would also benifit GREATLY from a simple user adjustable delay on each channel to help compensate for an odd speaker placement
Many mid- to high-end AC3 and DTS decoders already do allow you to adjust the delay on each channel. Not many people ask for this feature in low-end home theater set-ups, because they have no idea what it's supposed to sound like. Joe Sixpack doesn't know or care about seating position or speaker placement.
I know I'm glad I've worked with pro level equipment running concerts and such. Really opens your eyes to what needs to be there for a good clear sound.
I think that they majority of low- and mid-end home theater set-ups would get an immediate benefit from improved speaker design, probably more immediately noticeable than with balanced signal cables (although that would certainly be nice). Most of the speakers I've heard are built like this:
With "reflex" ports to increase low-end efficiency and "flatten" out the peak a little.
With mismatched mid-range and tweeters (with regard to efficiency).
Thin platic enclosures, or fiberboard lacking the appropriate amount of internal support.
Bass reflex ports are a way to flatten the response curve and extend the low end (just putting it out there; I'm sure you know all this already), but most cheap speakers aren't designed correctly (or can't be due to the size of the speaker), and the resulting sound is boomy and annoying. I guess it's just cheaper to use as little material as possible in the cabinet, then glue a tube to it.
A lot of speaker manufacturers seem to purposely mismatch higher-efficiency tweeters (or midrange drivers) with the other drivers in the cabinet. Due to the limiting factor of size, they'll never get it exact, since woofers need so much precious real estate (and air volume). But manufacturers aren't even trying to get close. The recent popularity of horn-loaded drivers makes the situation worse. Even though the resulting sound is not so great, it raises the average peak efficiency of the speaker system, and it makes for a nice number to print on a color brochure.
Many low-end home theater speakers are made of relatively thin plastic with no internal support. The surface area of the cabinet is probably radiating sound more efficiently than the drivers attached to it. Too bad the cabinet isn't designed to accurately reproduce this sound. It's big bucks before we get into enclosures with internal support or better materials.
***
Sellers need comparable figures to sell against their competition. Unfortunately, power output is the easiest one for consumers to understand. Some consumers have become mindful of speaker efficiency as well, but not too many really understand that the efficiency varies between drivers and depends on the frequency of the sound being reproduced, and they don't understand that the quoted figures for efficiency ar
Fred
"A fool and his freedom are soon parted"
-RMS
Did everyone fail to notice that Niro Nakamichi is behind this? Even if you haven't studied precedence and psychoacoustics, you should at least give the benefit of the doubt to a company founded by audiophiles, and that has always catered to audiophiles.
/., so it would behoove you to listen to it before you dismiss it out of hand. Don't just read the articles, read about the technology and the company behind the product.
/.
These aren't garage mechanics that had a paper-napkin idea. This is similar to what Polk delivered with the SRS series, but is done electronically. And while it's true that everyone's head and ears are shaped differently (and therefore respond differently to psychoacoustic phenomena), most serious research has shown that only people whose heads are dimensionally way outside of the norm hear "bizzare effects." 90% (or more) of the general population will be astounded, and will have a dramatically simpler system to set up.
Mr. Nakamichi's knowledge of psychoacoustics rivals that of EVERYONE reading
But wait... this is
Tim