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SAPSEC
12-20-2004, 07:02 AM
In home-theatre setup, is it mandatory to set up center channel
and front speakers with same brand. For instance, if I have BW (LCR3)
center speaker must I use also BW for front speakes (ie : DM-303) or I could
use pair of KEF Q-Compact for front speakers ? (same capacity : 8 ohms and 100w)

Will it create any sound or technical mismatch ? Thanks

kexodusc
12-20-2004, 07:25 AM
It's not important to have the exact same front three speakers, the same line of speakers, or even the same brand. However, the odds that your speakers will match go down considerably when you start mixing brands. You might get lucky, you might not...Alot of trial and error go into it.
The worst part is the tonal shift you get from left to center and back to right if the match isn't at least close. You can always adjust level settings for differences in sensitivity.
In the end though, remember this is a hobby for fun...don't put yourself in the poor house or get too stressed out if your speakers aren't perfectly timbre matched.

topspeed
12-20-2004, 08:11 AM
In addition to what kex has said, the importance of matching your front three ramps up dramatically if you plan on moving into hi-rez formats such as DVD-A or SACD. For HT apps, you might be able to get away with mismatched fronts as long as they are close in timbre. For hi-rez music, I'd be more inclined to stay within the same line of speakers.

Hope this helps.

Stu-r
12-26-2004, 07:33 PM
If you have a bookshelf speaker sitting around, just turn it on its side and try it for a center speaker. After listening and owning six "center" speakers, I decided not to be driven to a center speaker that cost more than my mains. I got a great buy on a good bookshelf unit that fills in the center very well, even on full symphony orchestra.

Geoffcin
12-27-2004, 06:14 AM
If you have a bookshelf speaker sitting around, just turn it on its side and try it for a center speaker. After listening and owning six "center" speakers, I decided not to be driven to a center speaker that cost more than my mains. I got a great buy on a good bookshelf unit that fills in the center very well, even on full symphony orchestra.

If your using a CRT monitor. Most "bookshelf" speakers have no magnetic shielding and will cause the picture to be distorted, or even worse, RUIN your picture tube. The profile of most "bookshelf" speakers are rather tubby too, and would look funny sitting on top of a TV. Also, and by far the most important is that bookshelf speakers were not designed for the proper dispersion pattern. Modern center channel speakers were designed from the ground up to have a very wide dispersion pattern. This is exactly what you want for a multiple seat home theater.

I've been into HT for over 20 years, and in my opinion the CENTER speaker is the most important of the speakers. I would not skimp on this speaker if your looking to put together a quality HT.

kexodusc
12-27-2004, 06:40 AM
I agree with Geoffcin completely... a center channel is usually designed for wider dispersion, extremely beneficial for Home Theater, and unshielded bookshelfs can be lethal to a TV
.
But over the last 9 yeas, with plenty of experimenting, I've come to realize that the importance of the center channel has been greatly exaggerated by the manufacturers who charge way too much for them compared to similarly sized bookshelf speakers
While I can't argue that 70% of info comes through the center channel, I can argue that a center channel will be better at producing ALL of this 70% of information than a bookshelf in the same roll.

For multi-channel music I'd advise against a horizontally oriented center channel. In fact, ITU standards strongly recommend AGAINST the use of a center channel for multi channel audio, in favour of identical speakers.
I'm in the middle of building some of my own, and until my center channnel is completed, I've been using an identical bookshelf model. Compared to my Paradigm Studio CC, I can honestly say I notice no deterioration in sound quality. But then, I sit almost on axis, I'm sure if I moved off axis more I might...who knows.

I think ideally a center channel speaker is preferable if you listen to alot of movies, and there are several people in the room, sitting off axis. I would argue this is what most people will look for when building home theaters, that are used for multiple purposes (ie: movies, multi-channel audio etc). This would validate buying a center channel.

Otherwise, I'm beginning to see what all the proponents of using bookshelfs for centers are talking about.

Stu-r
12-27-2004, 07:26 AM
If your using a CRT monitor. Most "bookshelf" speakers have no magnetic shielding and will cause the picture to be distorted, or even worse, RUIN your picture tube. The profile of most "bookshelf" speakers are rather tubby too, and would look funny sitting on top of a TV. Also, and by far the most important is that bookshelf speakers were not designed for the proper dispersion pattern. Modern center channel speakers were designed from the ground up to have a very wide dispersion pattern. This is exactly what you want for a multiple seat home theater.

I've been into HT for over 20 years, and in my opinion the CENTER speaker is the most important of the speakers. I would not skimp on this speaker if your looking to put together a quality HT.


I agree with your last paragraph. And possibly with your comment about the cosmetics. I've been in HT for 10 years, in stereo for 54, and have been a senior member of the Institute of Electrical and Electronics Engineers for 20. Also have twenty years in electronic warfare, analyzing antennas, radiation patterns, etc on American and foreign equipment. As a mattrer of fact, the study of wave propagation is what brought me to sound reproduction.

I've had six different center speakers during the past 10 years .... all unsatisfactory. I agree with you about the dispersion patterns. But the D'appolito array in center speakers is in the wrong plane. If you doubt this, look at D'appolito arrays in mains. The energy can't be distributed in the same plane when the array is rotated 90 degrees. For horizontal dispersion, either one is correct or the other is. Not both. The directivity of a two same-driver array is modest at best, anyway. But I think that the arrays on center speakers are a scam. An easy test would be to turn the center channel speaker on end and compare the distribution.

I checked on the shielding on the bookshelf speaker I'm using. Anyone can do this for himself by approaching the screen with the speaker and seeing if distortion in the picture occurs. Most current bookshelf speakers are shielded. And most television sets made during the past 20 years have degaussing loops built in. If one doesn't like the sonic result, he can always buy a center channel speaker. The odds are, if he has a decent bookshelf speaker, the drivers are better than what he'll find in a typical center speaker. The differences I note may be due to simply using a larger (6 1/2") driver. It sounds much better to me. Or, the bookshelf may be a higher quality unit than the centers I've had (including Definitive Technology and Paradigm).

To each his own, If you feel strongly about this, you might try a small, good quality bookshelf you have on hand and see if you note any difference, assuming the speaker is magnetically shielded.

Tarheel_
12-27-2004, 07:42 AM
not sure why no one ever recommends this idea, but do not use a center channel and assuming you have a newer receiver, let the receiver create a 'phantom' center. I use two floorstanding speakers with very good imaging and after two years, i still swear there is a center speaker in the room. I do toe-in a few degrees. My family has never complained about a lack of clear voices during movie playback. As for DVD-A and SACD, i have a few disks and i set my Pioneer (563A) player to 'no' center and again achieve very good results.

kexodusc
12-27-2004, 07:51 AM
Good point Tarheel, I was just trying that out the past few days, and if your main speakers are any good it can certainly provide pleasing results while saving you some money.

Geoffcin
12-27-2004, 08:10 AM
I've had six different center speakers during the past 10 years .... all unsatisfactory. I agree with you about the dispersion patterns. But the D'appolito array in center speakers is in the wrong plane. If you doubt this, look at D'appolito arrays in mains. The energy can't be distributed in the same plane when the array is rotated 90 degrees. For horizontal dispersion, either one is correct or the other is. Not both. The directivity of a two same-driver array is modest at best, anyway. But I think that the arrays on center speakers are a scam. An easy test would be to turn the center channel speaker on end and compare the distribution.

I checked on the shielding on the bookshelf speaker I'm using. Anyone can do this for himself by approaching the screen with the speaker and seeing if distortion in the picture occurs. Most current bookshelf speakers are shielded. And most television sets made during the past 20 years have degaussing loops built in. If one doesn't like the sonic result, he can always buy a center channel speaker. The odds are, if he has a decent bookshelf speaker, the drivers are better than what he'll find in a typical center speaker. The differences I note may be due to simply using a larger (6 1/2") driver. It sounds much better to me. Or, the bookshelf may be a higher quality unit than the centers I've had (including Definitive Technology and Paradigm).


It is also very large with TWO 6.5" woofers that go down to 40hz, and is capable of very high SPL. The difference between my center and a common bookshelf is that the tweeter/midrange array can be rotated 90 deg depending on it's use. I prefer a BIG center, and reccomend one if your looking for the best HT has to offer, so we are not in total disagreement. I also agree that a lot of centers, even ones that are expensive like B&W's lack some of the low end presence of the mid-sized bookshelf speakers.

Geoffcin
12-27-2004, 08:20 AM
not sure why no one ever recommends this idea, but do not use a center channel and assuming you have a newer receiver, let the receiver create a 'phantom' center. I use two floorstanding speakers with very good imaging and after two years, i still swear there is a center speaker in the room. I do toe-in a few degrees. My family has never complained about a lack of clear voices during movie playback. As for DVD-A and SACD, i have a few disks and i set my Pioneer (563A) player to 'no' center and again achieve very good results.

Can be perfectly fine for ONE center seating position, but any off axis seats will have a skewed presentation. It's no so much about clear voices, it's about their percieved position.

kexodusc
12-27-2004, 08:28 AM
Can be perfectly fine for ONE center seating position, but any off axis seats will have a skewed presentation. It's no so much about clear voices, it's about their percieved position.

This is true, off axis there's almost no center image in phantom center mode. To each their own.

Woochifer
12-27-2004, 01:22 PM
In general, you're best served by going with whatever center speaker matches the main speakers the best. The ideal match is three identical speakers up front, but the TV placement in most typical homes is the exact reason why horizontal center speakers exist. Nothing to do with technical superiority, just everyday practicality and a compromise by necessity.

If you can't go with three identical speakers up front, then typically your closest voice match will come from the center speaker made by the same manufacturer. However, I have heard some center speakers that poorly match the main speakers from the same manufacturer, and B&W did make one of them (the CC6, which was recommended for the previous 600 and 300 series). If the center speaker and mains have similar tonal characteristics, then it should work fine. However, if the center speaker sounds noticeably different than the mains, then that will present problems with the continuity of the front soundstage. The horizontal placement already ensures that the timbre match won't be perfect, and any further tonal shifts will make the center speaker stand out in a negative way. Even if the center speaker subjectively sounds better, it will still create a problem if its tonal characteristics differ a lot from the mains.

Tarheel's suggest of turning off the center channel is worth pursuing if you really can't find a set of mains that sufficiently matches the center. IMO, you're better served without a center speaker than going with one that poorly matches the mains. I would add though that if you can find a reasonably close timbre match, it is preferable to go with a center speaker, especially with movies because 5.1 soundtracks are typically mixed with a solidly anchored center channel that doesn't quite sound right when that channel is mixed down and split to the L and R mains.

Sir Terrence the Terrible
12-27-2004, 04:55 PM
not sure why no one ever recommends this idea, but do not use a center channel and assuming you have a newer receiver, let the receiver create a 'phantom' center. I use two floorstanding speakers with very good imaging and after two years, i still swear there is a center speaker in the room. I do toe-in a few degrees. My family has never complained about a lack of clear voices during movie playback. As for DVD-A and SACD, i have a few disks and i set my Pioneer (563A) player to 'no' center and again achieve very good results.


I would add though that if you can find a reasonably close timbre match, it is preferable to go with a center speaker, especially with movies because 5.1 soundtracks are typically mixed with a solidly anchored center channel that doesn't quite sound right when that channel is mixed down and split to the L and R mains.

Tarheel, Wooch has got it spot on the money with this comment. When the processor splits the center channel between the mains, it drops it in level 3db. When you have a movie like Twister which has dialog "fighting" with effects for intelligibility, that 3db's could mean the difference between hearing, and not hearing that dialog clearly.

When I was in film school, my instructor Tomlinson Holmann did a blind experiment on dialog intelligibility. He took two Thiel speakers(their top of the line model at that time which were an excellent speaker system in its own right) and ran them in the phantom mode with a movie with alot of effects while dialog was spoken, and compared it to three indentical high quality M&K speakers. Everyone in the experiment preferred the presentation WITH the dedicated center.

I am also of the belief that if you following the mixing chain's playback system(L,C,R,RS,LS and CS if applicable) you stand less of a chance of playback errors.

Stu-r
12-27-2004, 05:07 PM
It is also very large with TWO 6.5" woofers that go down to 40hz, and is capable of very high SPL. The difference between my center and a common bookshelf is that the tweeter/midrange array can be rotated 90 deg depending on it's use. I prefer a BIG center, and reccomend one if your looking for the best HT has to offer, so we are not in total disagreement. I also agree that a lot of centers, even ones that are expensive like B&W's lack some of the low end presence of the mid-sized bookshelf speakers.


Two 6 1/2s. That sounds like the way to go. What kind of bucks are you talking about for such a center?

Geoffcin
12-27-2004, 05:53 PM
Two 6 1/2s. That sounds like the way to go. What kind of bucks are you talking about for such a center?

My HT system is decidedly mid-fi, while my Audio system is not. I use Cambridge Soundworks speakers exclusively for my HT. My center speaker is their MC500, my mains the T500.

The MC500 is on sale, and will set you back $300.

http://www.cambridgesoundworks.com/store/category.cgi?category=spk_center&item=c1mc50ce

kexodusc
12-27-2004, 06:14 PM
Geoffcin's right...the Center Channels are probably the biggest rip-off in every speaker manufacturers catalog when you allow for materials, R&D, and packing, but all this aside, many speaker companies offer dual 6-1/2" woofer D'Appolito style MTM center channels...I've seen decent ones as low as $160. Whether they are a tonal match for your mains is another question.

Geoffcin
12-27-2004, 06:31 PM
Geoffcin's right...the Center Channels are probably the biggest rip-off in every speaker manufacturers catalog when you allow for materials, R&D, and packing, but all this aside, many speaker companies offer dual 6-1/2" woofer D'Appolito style MTM center channels...I've seen decent ones as low as $160. Whether they are a tonal match for your mains is another question.

The problem is is goes for a cool grand, ouch! I've heard the B&W center that goes for about $800, and it's got one kevlar 6.5" midrange/woofer and two silly looking ports.