Are the 'boom boxes' any good ?

Hello, i bought one of those Stereo-Mini Home Theaters (AIWA) and noticed that it has a
'Dolby Surround' logo and a 'Dolby Surround Mode'... so i connected my DVD player (PIONEER 515) to it. Now, i am not an expert in sound systems but quite honestly, i was not impressed with the sound quality offered, the boom box has 5 Speakers (Right,Center,LEft,RightSUr,LeftSUR) and most of the sound seems to come out the front speakers, and very little out of the rear surr speakers.I know that DVD offers 5.1 Dolby Digital Channels wich is more than the boom box can handle (only Dolby Surround) so my question is:

Is there a BIG difference between the sound quality i am getting than the one i would get with a proper 5.1 Digital decoder/amplifier ? in other words... am i missing a lot of the fun ?

Thanks !

Yes....Tried one of those setups for awhile and the sound of a properly configured 5.1 is way better.

Plain Dolby Surround...is notorious for lack of rear speaker use. (At least in my opinion)

[This message has been edited by Ma$ter-V (edited 01-17-2000).]

[Chromy]

On some movies, like action movies, you will find a huge difference. However, with other types of movies (chick flix come to mind ), while the difference is still there, it is more sublte.

Remember also that there shouldn't always be stuff coming from the surround speakers. Calibrate the system properly with test tones and you'll get to as close as it can get to a real theater.

Chromy

[Frankie]

You should also keep in mind that some movies default to plain surround or even mono. Make sure you go the setup or options at the beginning of the movie and select the appropriate sound field.

Ultimately you'll only get sound as good as your system can produce. A true DD system will make a big difference. Especially the new films.

[Taxi]

I have to agree with my compatriots. The difference between Dolby Pro Logic (Dolby Surround) and Dolby Digital and DTS is astounding.

[DJRobX]

Yep, the problem you describe has little to do with the Aiwa system's performance, but rather the limitation of the Dolby Surround encoding system.

Dolby surround works by performing special logic operations on the stereo signal to extract 4 channels. This system has major limitations. The channels are not discrete. Anything coming out of the rear will also be coming from the front two speakers. The rears will also pick up all sorts of noises intended for the front speakers. To compensate for that problem, the sounds are dulled down with a low-pass filter. Also, both the rears are attached together, so you won't hear things flying away in different directions. All of this spells lackluster and infrequently used surrounds.

Dolby Digital 5.1, on the other hand, has 5 dedicated, full-range channels. When something comes out those rear speakers, it was MEANT to be there, and will be there in its full glory. Since the rears won't muck up the sound from the front, they're used much more frequently in dedicated 5.1 soundtracks.

Once you go 5.1 you'll never go back.

The problem you are experiencing has very little to do with the limitations of the Dolby Surround system, which up until a few years ago was state of the art for cinemas the world over. Rather it is the electronics you have purchased. Any 'boom' box will not be able to offer the same level of control, seperation and indeed integration of a properley calibrated seperates system. I must take issue, again, with some of the above post in that although not discrete Dolby Surround does offer seperation between the channels and that information recorded in the rear surrounds should not be 'bleeding' to the front channels. This is a symptom of poor quality eqiupment rather than the encoding itself. Dolby Surround offers three seperate front channels and a mono rear channel reproduced through two stereo speakers for an even spread behind the listening position. Properley calibrated Dolby Surround can sound surprisingly good I can assure you. The difference between Surround and 5.1 and Dts is remarkable however, as has already been pointed out. The level of dynamics, detail, seperation and sheer control from all channels is astounding and something of which we are very proud. This is why it is necessary to have full range speakers on all channels and why Dolby will not licence Dolby Digital to be used on 'boom' boxes - they simply wouldn't cope! Hope that helps.

Justin Pledger
Dolby Laboratories

[DJRobX]

I do not challenge that Dolby Surround was the state of the art at one point. But to anyone who's heard 5.1 sound (which would likely be anyone who's been in the theater within the last decade), Dolby Surround will probably sound lackluster.

I do stand corrected on the front/rear separation issue (specifically the front speakers reproducing what the rears are outputting), the documents I had read were on Dolby Surround and not Pro-Logic decoding.

However, the surrounds are still limited in range, and do pick up unintended signal, even on good quality consumer equipment. And, in general, movies that employ Dolby Surround just aren't as active as 5.1 mixes, which is probably why he's so unhappy with his Dolby Surround setup, regardless of whether it's coming out of a "Boom Box" or a $2000 receiver.

This isn't to say that Dolby Surround is bad; it's a marked improvement over flat stereo. But if active surrounds is what he's looking for, he needs to be looking into a 5.1 system.



[This message has been edited by DJRobX (edited 02-01-2000).]