Center Channel Frequency Response


I have to go with one system for all -- don't have the luxury of one system for movies and another for music. I found this response in an old thread:
A center channel speaker that is expressly designed for HT will have a restricted and taylored frequency response which makes speech more easily intelegible. However, such a speaker is not good for multichannel music, where the center (and surrounds) should be the same as the left and right fronts.

First question: Is the underlying premise correct? Are HT soundtracks and multichannel music formats mixed differently with respect to the frequency range of the center channel?

Second question: If the answer to the first question is "yes," why would a more restricted frequency range on the center channel make dialog clearer? Seems to me a clear midrange is a clear midrange. Am I missing something?

Thanks,
Lou
lhf63
>First question: Is the underlying premise correct?

Anecdotally, 60% of a motion picture soundtrack's energy ends up in the center channel. It gets more than its fair share of the musical score and effects.
Thanks, guys. Makes sense to me to have as full-range a center speaker as funds and space permit. And, Kal, yeah -- ditto for "intelligible."

Lou
I thought "taylored" was more egregious. I do not understand anyone posting without an active spell-checker.

Kal
That quote was from me. OK, OK, so I don't always spell correctly. I'm sure you guys never make a mistake.

You guys really need to do some research about reproducing speech for best intelligibility. Much research has been done on this subject, particularly in context of hearing impairment and high noise environments. Note that I referred to dialogue in movies, not singing.

Here is a sample quote from one paper...

"High-quality speech systems need to cover the frequency range of about 80 Hz (for especially deep male voices) to about 10 kHz (for best reproduction of consonants, which are crucial to intelligibility). Response below 80 Hz must be eliminated to the extent possible: not only do these frequencies fall below the range of the speech signal, but also they will cause particularly destructive masking at high sound levels."
"High-quality speech systems need to cover the frequency range of about 80 Hz (for especially deep male voices) to about 10 kHz (for best reproduction of consonants, which are crucial to intelligibility). Response below 80 Hz must be eliminated to the extent possible: not only do these frequencies fall below the range of the speech signal, but also they will cause particularly destructive masking at high sound levels."

So, 80 to 10kHz is necessary, OK. However, eliminating response outside that range is either irrelevant (if there is no signal content outside the range) or a big mistake resulting in loss of program material (if there is signal content outside the range). So, if it is the latter, one may achieve some advantage in voice intelligibility but at the cost of loss of other content. IMHO, a bad trade-off.

Kal