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Hoho
01-05-2004, 04:28 PM
What is known - and how much is known, about what would make one speaker or system better than another at intelligibility (hearing spoken or sung words as clearly enunciated)?

I would think that vocals would come across better if the music or sound effects were attenuated. So high fidelity and flat frequency response might actually not be good for making out television dialogue and the like.

I would also guess that diffusion of sound, such as from a dipole or bipole speaker, while it has its virtues, might also make words harder to discern.

Woochifer
01-05-2004, 05:16 PM
I don't see any reason why a speaker with more accurate frequency response would be less intelligible than one that has more fluctuations throughout the frequency range. The key to dialog intelligiblity in a home theatre system has a lot of to do with having the correct levels set for all channels (using a SPL meter to verify the settings), minimizing room echo and reverberation, and how well matched all of the speakers are. Changing from one brand to another if you're talking about any kind of midpriced speaker will not have nearly as much effect with regard to intelligiblity as those factors will.

Sir Terrence the Terrible
01-06-2004, 12:39 PM
What is known - and how much is known, about what would make one speaker or system better than another at intelligibility (hearing spoken or sung words as clearly enunciated)?

I would think that vocals would come across better if the music or sound effects were attenuated. So high fidelity and flat frequency response might actually not be good for making out television dialogue and the like.

I would also guess that diffusion of sound, such as from a dipole or bipole speaker, while it has its virtues, might also make words harder to discern.

Just to add to the great comments of my pal the Wooch man, Intelligibility is also a function of dispersion. Speakers that actively interact with the walls and floor of a room have a reduction in clarity factor according to tests performed by Tomlinson Holmann formerly of THX. This is the very basis of THX requirements for narrow vertical dispersion and wide horizontal dispersion. Since the center speaker is the furthest from the walls, it pays no penalty for wide dispersion.
What is clearly understood is the three front speakers MUST be matched, or dialog intelligibility will suffer in the face of music and effects
This is why it is BEST to have three matched(or identical) speakers in the frontal hemisphere.

Bipolar or dipolars are not recommended for placement in the frontal hemispheres of hometheaters. Their interaction with the rear, side, floor, and ceiling makes their clarity factor far below what is desireable for dialog intelligibility. They also create excess reflections which harm precise imaging, and changes the frequency response of signals designed for more directional(and less interactive) speakers.

As far as making television dialog more clear you must understand that television sound in general goes through a tremendous amount of processing not only during the mixing stage, but in transmission to avoid overloading the transmission system itself. From the time the soundtrack leaves the post production stage and starts throught the transmission system, compression and limiting will have altered the tonal structure of the mix. In this case, the system itself may pose more of a problem on dialog intelligibility than any speaker could.

Kursun
01-06-2004, 01:02 PM
I would say that a bright speaker with accentuated upper-midrange and a well controlled mid-bass with no boom surely would increase intelligibility.

topspeed
01-06-2004, 03:39 PM
Along with the great points being made regarding room reflections/interaction is the speaker itself. Driver choice, box colorations, diffusion patters, crossover, etc. will all play a part. As Sir TT noted, your source is also going to contribute mightily, perhaps more than anything else on highly accurate systems (garbage in=garbage out). Let's not forget personal preference while we're at it. Some people may feel that dialogue is more accurate with a mid-bass hump thereby giving the voices more weight while others may consider the more sibilant nature of a bright/hot tweeter to equal clarity. Unless you're in the studio hearing the recording live and unmiked, do we really know what the artist's sound like?

Just a thought...

Sir Terrence the Terrible
01-06-2004, 04:22 PM
I would say that a bright speaker with accentuated upper-midrange and a well controlled mid-bass with no boom surely would increase intelligibility.

Maybe it would at the expense of balance for other effects and music that are also found in the center channel. Also you still have to deal with the center speaker matching the L/R mains, or that center speaker with the bright accenuated midrange would stick out like a sore thumb during panning accross the front three channels. You are looking at things from a slightly smaller perspective than should be. You must look at the whole system rather than a single speakers frequency response. Also, bright sounding speakers have the distinction of being very fatiguing during long listening sessions. That would be somewhat undesireable when watching a 2.5 hour movie.

nick4433
01-06-2004, 05:01 PM
"I would think that vocals would come across better if the music or sound effects were attenuated. So high fidelity and flat frequency response might actually not be good for making out television dialogue and the like"

My question to HoHo is since you feel the need to attenuate certain frequencies, What source is it exactly that seems to render dialog intelligible? Is it Television only or DVD, etc.?
Wooch and Sir TT have already made great points with respect to this but I want to add that if you are feeding line outs from your TV directly to your receiver or prepro then that is a mistake as that sound quality is total garbage as someone above noted.
If you have a satellite receiver or a cable box or even a VCR, I'd go that route. I am also assuming that you have a multi speaker setup in which you also have a center speaker. Weak dialog in the center channel could be all those reasons Wooch mentioned but it could also mean weak power to the center speaker. My center channel speaker sounds great when connected to an external amp as opposed to a receiver powering it. When using an amp, the dialog is much more crisper and easy to understand and I'm not necessarily suggesting its loud but its very intelligible. I had a Denon 4802 and no matter how much I adjusted with an SPL meter, I had to bump up the center channel a few DBs higher than the others.

kelsci
01-06-2004, 05:53 PM
Speech intelligibility from the center channel has been a great topic of concern for us hobbyist particulaly since the oncome of the surround formats matrix and in particular descrete.

Some 10 years ago or perhaps longer than that, in a sound room at a local higher end store, I demonstrated to my salesmen friends the 5 channel dynaquad system I used in a smaller version with smaller speakers. Now at that time, the Lexicon CP1 Pro-Logic processor was hooked up to equipment of all sorts in that same room. My sales friend who had sold me my NAD receiver listened to this concoction that I hooked up in the store work. The main comment he had was that my system beat the CP-1 in dialogue reproduction. In a DPL system, of course the dialogue was steered to the center channel. The main left and right speakers only contain sound effects and off stage dialogue with virtually little or no leakage of center channel dialogue. DPL was created not to be a true sweet spot system so more than one listener could have the surround effect something resembling the movie theater. The system I deployed however was a SWEET SPOT SYSTEM. The most people that could listen to it was two people. The left and right main speakers were still reprocuing dialogue for the center. However, the nature of the 3 speaker dynaquad decoding circuit created rear surround effects with its final effect funneling a FILL-IN dialogue channel into its center speaker. A kind of focusing took place in the sweet spot from that fill in center channel. So three sets of speakers in the front were reproducing dialogue and as a result the dialogue maintained its intelligibility but sitting in the sweet spot kept this intelligent dialogue reproduction centered.

The discrete systems we use today like DPL also focus a dialogue channel in the center. It appears that we use some kind of D'Appolito speaker set-up vertically on top or below our tv sets for dialogue although some system deploy a equal size speaker clone resembling the mains and surrounds(specifically referring to the sub-satellite set-up in some cases). Again like DPL we want to have more than one listener be able to hear dialogue from the center like the movie theater. There are IMHO two ways that might correct this problem. Like the Dynaco system, the left and right speakers would have to contain some center channel dialogue. The second way is that the current center channel design which I see has been futzed with by some companies have added a midrange speaker below the center tweeter in that D'Applolito design. I think they are on the right track, but the speaker is in the wrong place. A modification is needed in the center channel so that across its front you have a woofer-midrange-tweeter-midrange-woofer set-up. I presented this aspect a few years back on the old E-town websight, with a response about LOBING creating a problem. Why not built a prototype first and then see what happens. Those who understand something about the nature of home theater should be willing to try something which in this case would be simple to create in a speaker manufacturers realm. I think the probability on this is that this extented D'Appolito design will not do any harm in its so called LOBING effect, but instead may supply the answer that we need for intellibility of that very important center channel.

Crunchyriff
01-07-2004, 06:26 AM
Another aspect you may want to consider is line conditioning- i.e., 'clean power'.
Many have claimed slight to much more clear, precise audio. If you aren't using anything for this, such as something from Paramax or Monster, you may want to look into it.

I'm not using anything like this yet, and am thinking of giving it a try.

Willow
01-07-2004, 06:32 AM
cleanpower... I bought a power bar by RCA performance series it has a built in filter I paid 29$cad for it and it works. Proof...well on a particular commercial there was always some snow "noise" I have ben waiting 2 weeks to see this commercial again and the other day it was on and NO static....wow this sure beat the Monster at 100$

Crunchyriff
01-07-2004, 05:04 PM
Willow- If the $29 unit from RCA works, I wonder how much better the Monster series will work? (I'm not slagging the RCA)

I know there are naysayers, but being a pro guitartist, (30 years of playing this year) I know what 'dirty power' & interference will do to my guitar rig, let alone the PA system. The power filtering concept is far from snake oil. And this purchase I have been putting off for some time.

Put it this way...when you go to the gas station, god only knows what goes into yer tank- it's up to your filter to clean the fuel before it gets to the engine. As long as there isn't water in it, it can be pretty dirty, and the filter will grab the garbage, and give you clean fuel. The same concept can be applied to electricity. Who cares if it IS unfiltered, dirty, or whatever, before it gets to your home? (as some argue) That's not the point. The gas supplier does NOT guarantee purity, and neither does a generating station. Even a 'dedicated A/C line' installed for HT could still be 'dirty', unless you are filtering it as it comes into the dedicated circuit; and even then there is no guarantee that it will be 'clean'...unless this circuit is on a wing of your home totally removed and shielded from any other possible sources of interference. Therefore, I want the filter placed just before the current gets to my gear.

I'm gonna try one of those Monster HTS 3500 MKII boxes on our HT rig.

HoHo- didn't mean to hijack YOUR thread...I'll shut up now....