psg Posted October 24, 2006 Share Posted October 24, 2006 This came up on AVS, linked from yet another forum. I'll dig up the references if there is interest. The real reason to have a center channel, and not use phantom mode, is the crappy design of Dolby Digital. You all know Dymanic Range Control (DRC), commonly known as midnight-mode. It's the setting that you use if you don't want to disturb your sleeping family, or neighbours in an appartment building. It reduces dynamic range considerably (from 6 to as much as 18 dB, I think). It appears that DRC is enabled automatically, in spite of the user not having set it, when any downmixing occurs on Doldy Digital content on the vast majority of receivers (it's in the Dolby spec). This downmixing includes 5.1 to 4.1 (e.g. phantom mode for no center speaker)! So if you use phantom-mode, then you are robbed of the great dynamic range we Klipsch owners so enjoy. This seems like a major flaw in Dolby Digital (it doesn't happen for DTS), since all they needed to do to prevent digital clipping when summing signals was simply to start off by lowering them all by the required number of dB. But it appears to be true. I ran a small test myself, playing the opening scene of Scooby-Doo 2 in 5.1 and then again in phantom mode. The dialog was the same level in both cases, but action peaks were nearly 10 dB lower in phantom mode. Interesting huh? Quote Link to comment Share on other sites More sharing options...
Moderators dtel Posted October 25, 2006 Moderators Share Posted October 25, 2006 That could easily explain why when I went from phantom to a real center the whole setup sounded so much better , had no Idea. Now if they could mix the voices to a more reasonable level that would help. On most movies when someone talks at lower than normal level you can barely make out what the are saying. My speakers are all set with a db meter and are the same model Forte ll. If you have the volume set where you can easily hear a voice whisper when some action happens even just a door slamming people jump off the sofa, and if there was an explosion or gunshot people freak. Sometimes I do it on purpose if I know what scene is upcoming , I have actually had tears from laughing when someone actually jumps off the sofa, my wife refuses to watch scary movies period. They keep bringing movies to watch though, must be something to it ![] Quote Link to comment Share on other sites More sharing options...
jacksonbart Posted October 25, 2006 Share Posted October 25, 2006 For the same reason why I don't have Phantom front left and right speakers. Quote Link to comment Share on other sites More sharing options...
JJkizak Posted October 25, 2006 Share Posted October 25, 2006 I believe the "low voice volume thing" started in the THX era. If you are hard of hearing and crank up the volume everybody else with normal hearing has to wear earmuffs. JJK Quote Link to comment Share on other sites More sharing options...
psg Posted October 25, 2006 Author Share Posted October 25, 2006 I thought this topic would have sparked a bigger interest. Well, this was news to me. I was quite surprised. It's quite a good reason to have a complete 5.1 system. I wonder if the news HD Dolby Digital has the same drawback... Quote Link to comment Share on other sites More sharing options...
TheEAR Posted October 25, 2006 Share Posted October 25, 2006 It is some news for sure PSG,but as it stands Dolby Digital satisfies the masses. And is optimised for the masses,masses who own less than stellar gear. As long as it sound good,close your eyes and listen,sometimes not knowing is best [] Quote Link to comment Share on other sites More sharing options...
Zen Traveler Posted October 25, 2006 Share Posted October 25, 2006 I thought this topic would have sparked a bigger interest. I think it is interesting, but I agree with Ear--Sometimes you don't care how sausage is made.[] Quote Link to comment Share on other sites More sharing options...
DrWho Posted October 26, 2006 Share Posted October 26, 2006 So how does one go about bypassing the compression? I wonder if it wasn't intentional to make a more drastic difference between LR and LCR front arrays...thus inducing more speaker sales. Quote Link to comment Share on other sites More sharing options...
psg Posted October 26, 2006 Author Share Posted October 26, 2006 So how does one go about bypassing the compression? I wonder if it wasn't intentional to make a more drastic difference between LR and LCR front arrays...thus inducing more speaker sales. A few high-end receivers allow you to specifically override it AFAICT. But it would likely be cheaper to buy a center speaker than such a receiver. [] I guess it means that if a friend is serious about HT sound, you should recommend a hard center speaker even for single-person viewing. Phantom-mode won't cut it. (I'm assuming that forum members already all have a center speaker! Ha ha!) Quote Link to comment Share on other sites More sharing options...
DrWho Posted October 26, 2006 Share Posted October 26, 2006 One of the things I would like to experiment with is running the reciever in phantom stereo mode and then implementing a 3rd channel stereo minibox thing...but with the compression that kinda defeats the purpose. Quote Link to comment Share on other sites More sharing options...
el jopez Posted October 26, 2006 Share Posted October 26, 2006 Now would this codec limitation be limited to only big box retail receivers or to all receivers/processors? Quote Link to comment Share on other sites More sharing options...
jacksonbart Posted October 26, 2006 Share Posted October 26, 2006 How can I run 5.1 in phantom with no speakers? I sure Bose will have a product for that. Quote Link to comment Share on other sites More sharing options...
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