I have been reading and trying to prioritize the qualities that one would privilege in a Home Theater center channel speaker.
My HT uses KEF 105.2 as the front mains and there are 2 subwoofers in this 7.2 all KEF system. As for the drivers on hand, I have 2 KEF B110's and 2 KEF T52's and assorted KEF woofers B139 and B200 in boxes ready for action.
So, what makes the most sense?
If the main work of a center channel is dialog and to "center" the sound stage, it does not seem to require lots of bass. And with 2 sub's up front I don't see that it is critical. But I can drive it with any amp I like and it is as hard to build a 3way that goes down to 25Hz as a 2way that goes down to 60Hz.
Also, I see a lot of horizontal MTM designs and with all the issues of orienting the baffle horizontal, am pleased to report I can be vertical if I choose, and be fine with space. I can make it a 3way for that matter. With the mission to build a no compromise center channel to compliment the 105.2's I would appreciate recommendations and rationales.
Thank you.
My HT uses KEF 105.2 as the front mains and there are 2 subwoofers in this 7.2 all KEF system. As for the drivers on hand, I have 2 KEF B110's and 2 KEF T52's and assorted KEF woofers B139 and B200 in boxes ready for action.
So, what makes the most sense?
If the main work of a center channel is dialog and to "center" the sound stage, it does not seem to require lots of bass. And with 2 sub's up front I don't see that it is critical. But I can drive it with any amp I like and it is as hard to build a 3way that goes down to 25Hz as a 2way that goes down to 60Hz.
Also, I see a lot of horizontal MTM designs and with all the issues of orienting the baffle horizontal, am pleased to report I can be vertical if I choose, and be fine with space. I can make it a 3way for that matter. With the mission to build a no compromise center channel to compliment the 105.2's I would appreciate recommendations and rationales.
Thank you.
+1 on using phantom if practical, otherwise....... your mains are only rated to 38 Hz whereas movies are normally mixed to 20 Hz in 'full' mode, so you may need to high pass all the mains, surround channels for some 'reference bass' mixed movies, especially if the system is set to the THX reference SPL.
This increases the LFE channel's requirements up to ~+7 dB IIRC [5x more acoustic power], so you might damage your subs with these movies if they don't have adequate protection circuits.
Then there's the extremely low bass [< 10 Hz down to near Dc!] some movies have that has blown quite a few cheap and not so cheap woofers, especially vented ones, so a good high pass for the LFE channel is mandatory unless one has a very large multiple driver sealed sub system.
Both more good reasons for using a distributed sub system as there's 'no replacement for displacement', only a point of diminishing returns.
GM
This increases the LFE channel's requirements up to ~+7 dB IIRC [5x more acoustic power], so you might damage your subs with these movies if they don't have adequate protection circuits.
Then there's the extremely low bass [< 10 Hz down to near Dc!] some movies have that has blown quite a few cheap and not so cheap woofers, especially vented ones, so a good high pass for the LFE channel is mandatory unless one has a very large multiple driver sealed sub system.
Both more good reasons for using a distributed sub system as there's 'no replacement for displacement', only a point of diminishing returns.
GM
The amount of hype in the HT "literature" is way beyond even what I am used to in ad driven audio magazines (suitable only for the bottom of bird cages). I have not picked up an Ultimate Sound style magazine in decades and only see these sorts of articles when a link sends me there. These "journalists" all seem to be reading the same copy, and "the center channel is system critical, anchoring the dialog", yada yada. Then a couple guys I trust weigh in telling me to loose it altogether! Bad for sales. Now I am thinking that in a family den this advise is consistent with my experience setting up Stereo reference systems in the same space.
I assume that DVD content is produced channel specific. But, even if it is, I understand the challenge of creating a realistic soundstage in only a 12' wall to wall room and it is not the same problem a theater with 60' screens have. So, back to the drawing boards with one less speaker to think about.
I will have to rethink this issue of bass. And while I have a bit more extension (I use B139's in sealed 60L monkey coffins and not the B300's) the point about the demands of HT with a Stegosaurus bouncing rather than Stradivarius bowing is well taken.
With a 416-8B/811B project forming up the big KEF's are pushing the little KEF 2005's out of the den. Maybe it's time to squeeze some more bottom out of them. The rubber surrounds on all these drivers have held up well over the years. Wish I could build a new body for me as easy as a new cabinet for a driver.
I assume that DVD content is produced channel specific. But, even if it is, I understand the challenge of creating a realistic soundstage in only a 12' wall to wall room and it is not the same problem a theater with 60' screens have. So, back to the drawing boards with one less speaker to think about.
I will have to rethink this issue of bass. And while I have a bit more extension (I use B139's in sealed 60L monkey coffins and not the B300's) the point about the demands of HT with a Stegosaurus bouncing rather than Stradivarius bowing is well taken.
With a 416-8B/811B project forming up the big KEF's are pushing the little KEF 2005's out of the den. Maybe it's time to squeeze some more bottom out of them. The rubber surrounds on all these drivers have held up well over the years. Wish I could build a new body for me as easy as a new cabinet for a driver.
Well, one valid reason for the CC hype is that most folks start a HT using either their stereo system or buy a HTiB; plus, not all movies are mixed to meet THX specs nor are all processor/receivers equal in their ability to sort it all out.
Combined with a shift in recent years to put more of the front channel's signal into the CC, relegating the L/R mains to panning duty same as in a pre-THX type multiple channel cinema app [presumably to force folks to use a CC or suffer poor dialog intelligibility], this in turn ideally requires the CC to be at least = to, and ideally superior to, the L/R 's performance, so the subliminal message apparently is: buy a profit loaded Soundbar.
If you move up to an Altec/GPA or similar type L/R system, then a CC option is limited to building a third one.
Me too, though by now I'd need to be at somewhere around GM v50.2
GM
Combined with a shift in recent years to put more of the front channel's signal into the CC, relegating the L/R mains to panning duty same as in a pre-THX type multiple channel cinema app [presumably to force folks to use a CC or suffer poor dialog intelligibility], this in turn ideally requires the CC to be at least = to, and ideally superior to, the L/R 's performance, so the subliminal message apparently is: buy a profit loaded Soundbar.
If you move up to an Altec/GPA or similar type L/R system, then a CC option is limited to building a third one.
Me too, though by now I'd need to be at somewhere around GM v50.2
GM
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Coming from a cinema background - I was a projectionist and also did Dolby and THX alignments - I think the Center Channel is THE most important. If I could have only one, the CC would be it. That's how movies, and now television, are mixed and mastered.
For pure music systems I can live without a center channel, despite some shortcomings. It usually is not needed.
If you want to understand the dialog best, then the CC is what you need. Dialog is mixed there, with few exceptions. It does seem television sound editors/mixers are getting more adventurous these days, but the CC is still the anchor. And while a phantom center image can work OK, it never has the same clarity as an actual source at that position. There is usually a tonality shift in the center phantom image, making it a bit darker than the left-right. Not so great for dialog. I have used a phase shuffler to eliminate that dip caused by comb filtering.
A number of studies I've read, and can not find again (of course!) concluded that the most important thing in a L-C-R setup is for the 3 speakers to be identical. Identical speakers trumps better quality speakers. Not what we'd like to hear, as it's tempting to cheat with the center because it only carries dialog.
I hope that stirs the waters enough for you.
For pure music systems I can live without a center channel, despite some shortcomings. It usually is not needed.
If you want to understand the dialog best, then the CC is what you need. Dialog is mixed there, with few exceptions. It does seem television sound editors/mixers are getting more adventurous these days, but the CC is still the anchor. And while a phantom center image can work OK, it never has the same clarity as an actual source at that position. There is usually a tonality shift in the center phantom image, making it a bit darker than the left-right. Not so great for dialog. I have used a phase shuffler to eliminate that dip caused by comb filtering.
A number of studies I've read, and can not find again (of course!) concluded that the most important thing in a L-C-R setup is for the 3 speakers to be identical. Identical speakers trumps better quality speakers. Not what we'd like to hear, as it's tempting to cheat with the center because it only carries dialog.
I hope that stirs the waters enough for you.
The thing about being a hobbyist is that there are always boxes of drivers and sheets of plywood collecting dust in the garage. It would be different going to an audio saloon and spending real money on audio "investments". Who has not deluded themselves that this stuff is an investment? LOL. Maybe retirement in old McIntosh, Levinson, or Krell boxes under a bridge?
I have not given the HT much thought and currently use a store bought turnkey KEF 2005 5.1 that is "good enough" for TV. But something has shifted, likely me, and now "HT" content is more interesting and fun.
I like waters that are stirred. It almost always means there are contexts where alternate positions are more correct than not. The thing to do is to build a CC speaker and figure out when a CC is critical and when the system would do better with this phantom option.
I have a pair of KEF B110 and T52 currently unemployed as well as a B139, a couple B200's and woofers of other species around the house.
So, I can fashion another 105.2 top and bottom.
I can build just the 105.2 top and let the B110 roll off as in the LS3/5A.
I could do a 104.2 style MTM top and/or mate it to a B139 bottom.
Is there a clear winner? Well, maybe not clear, but one that gets a nod?
I have not given the HT much thought and currently use a store bought turnkey KEF 2005 5.1 that is "good enough" for TV. But something has shifted, likely me, and now "HT" content is more interesting and fun.
I like waters that are stirred. It almost always means there are contexts where alternate positions are more correct than not. The thing to do is to build a CC speaker and figure out when a CC is critical and when the system would do better with this phantom option.
I have a pair of KEF B110 and T52 currently unemployed as well as a B139, a couple B200's and woofers of other species around the house.
So, I can fashion another 105.2 top and bottom.
I can build just the 105.2 top and let the B110 roll off as in the LS3/5A.
I could do a 104.2 style MTM top and/or mate it to a B139 bottom.
Is there a clear winner? Well, maybe not clear, but one that gets a nod?
I don't know the KEF stuff well enough to comment.
I can say that just adding just a center midrange horn - 500Hz-5Khz - to my A5 system did help peg the center image. Getting the level right was never easy, tho. But it worked well for theater stuff and radio plays.
The phase shuffler did about as well, once the system was well tweaked.
I can say that just adding just a center midrange horn - 500Hz-5Khz - to my A5 system did help peg the center image. Getting the level right was never easy, tho. But it worked well for theater stuff and radio plays.
The phase shuffler did about as well, once the system was well tweaked.
I have been unsure how much duty the CC does. So, I now have 2 rebuttable propositions from noted experts.
The CC can be non-existent - a phantom, or it is a mission critical component in a HT system.
It likely "depends."
In testing these propositions it seems your opinion would be to duplicate the LC/RC exactly. Then I would build another 105.2, a 3way.
But, if the CC does not carry much below 80Hz, it can be as small as 12" H by 7.5" W by 6.25" D. Enclosure volume: 5 liters (LS3/5A substituting a T52 for the T27) or a 2way.
And, if the CC performance would be enhanced with an MTM of the same drivers as the LF and RF, It would be easy pie to fashion 2xB110+T52 in the style of the top of the KEF 104.2, with or without the LF. An MTM 2way or an MTM 3way.
There is no difference in materials or in effort so, all things really are equal, what would the most promising build be?
The CC can be non-existent - a phantom, or it is a mission critical component in a HT system.
It likely "depends."
In testing these propositions it seems your opinion would be to duplicate the LC/RC exactly. Then I would build another 105.2, a 3way.
But, if the CC does not carry much below 80Hz, it can be as small as 12" H by 7.5" W by 6.25" D. Enclosure volume: 5 liters (LS3/5A substituting a T52 for the T27) or a 2way.
And, if the CC performance would be enhanced with an MTM of the same drivers as the LF and RF, It would be easy pie to fashion 2xB110+T52 in the style of the top of the KEF 104.2, with or without the LF. An MTM 2way or an MTM 3way.
There is no difference in materials or in effort so, all things really are equal, what would the most promising build be?
As far as I know, it does. At least in cinema mixes because LCR speakers behind the screen are normally identical. Subs get their own channel. But taht is going to depend on the mix itself and how it is decoded.
Of course we can cheat in HT and push some center bass off to the side speakers and/or the sub with decoding and processing. That way you can use a smaller center speaker below the screen. Putting it behind the TV often doesn't sound so great.
From my experience, I'd make the center as much like the left and right as possible, then high pass it if need be.
Talking about for movie & TV soundtracks here, not for music.
I'd be curious to know what the standard practice is for DVD and Bluray mixes - if there is one. Early in the life of DVD there was talk that the cinema mix just got dumped onto DVD and that was not optimum. That has changed a lot, hasn't it?
More of a Home Theater Shack question than diyAudio.
More of a Home Theater Shack question than diyAudio.
I have been looking into the AV and HT forums to answer just this question. And I am getting a lay of the land.
First of all, a shout out and praise for the ubiquitous GM. This is a man with a mission and very much out there in HT and AVI land. People consistently ask the most impossible, poorly conceived, entitled questions and GM answers them in the most consistently respectful and objective way imaginable. Pure kindness and grace. "Greets!"
Anyhoo, it is a brave new world and the acronym learning curve is intense. I will figure this out in time, but there appears to be a number of competing ideas fueled by the excitement and commitment of the inventors and, predictably, the competition for market and profit. Nothing wrong with competition and profit, and we need to go no further than Edison for the pure type entrepreneur in audio. But it is a Tower of Babel with no tower in sight.
My plan going forward is to figure out JRiver Media Center and stay as independent as possible of the all in ones, at the amplifier/driver stage of things. I will just roll with the pre-amp processors that seem to come and go. I have experience with amplifiers and speakers and have a lay understanding of how to purpose them. At Pano's recommendation I purchased the Focusrite Scarlett 6i6 to interface my computer source. I am not yet convinced this stuff is not going to sound like a tin can compared to vinyl/tubes/classic drivers but I have an open mind and remember my first computer, an S-100 Z-80 running CPM with all of 16K of memory. It kind of feels like that right now. And it requires curmudgeons holding down standards to keep it honest. I just shake my head when I read these AV forums and people talking about being unable to hear the difference between amplifiers or sources. It is like people unable to distinguish one box wine from another box wine. They are all dreadful.
There is good HT information on diyAudio but it is spread around. Maybe I have missed it, but there should be a Home Theater forum given the convergence of these technologies on DIY. I don't have the engineering background to easily follow most content on diyAudio but with some patience and research I can usually figure it out and it is so much more helpful than the commercial driven Babbit and Bromide that I have been reading on these other forums.
First of all, a shout out and praise for the ubiquitous GM. This is a man with a mission and very much out there in HT and AVI land. People consistently ask the most impossible, poorly conceived, entitled questions and GM answers them in the most consistently respectful and objective way imaginable. Pure kindness and grace. "Greets!"
Anyhoo, it is a brave new world and the acronym learning curve is intense. I will figure this out in time, but there appears to be a number of competing ideas fueled by the excitement and commitment of the inventors and, predictably, the competition for market and profit. Nothing wrong with competition and profit, and we need to go no further than Edison for the pure type entrepreneur in audio. But it is a Tower of Babel with no tower in sight.
My plan going forward is to figure out JRiver Media Center and stay as independent as possible of the all in ones, at the amplifier/driver stage of things. I will just roll with the pre-amp processors that seem to come and go. I have experience with amplifiers and speakers and have a lay understanding of how to purpose them. At Pano's recommendation I purchased the Focusrite Scarlett 6i6 to interface my computer source. I am not yet convinced this stuff is not going to sound like a tin can compared to vinyl/tubes/classic drivers but I have an open mind and remember my first computer, an S-100 Z-80 running CPM with all of 16K of memory. It kind of feels like that right now. And it requires curmudgeons holding down standards to keep it honest. I just shake my head when I read these AV forums and people talking about being unable to hear the difference between amplifiers or sources. It is like people unable to distinguish one box wine from another box wine. They are all dreadful.
There is good HT information on diyAudio but it is spread around. Maybe I have missed it, but there should be a Home Theater forum given the convergence of these technologies on DIY. I don't have the engineering background to easily follow most content on diyAudio but with some patience and research I can usually figure it out and it is so much more helpful than the commercial driven Babbit and Bromide that I have been reading on these other forums.
Cool! Let us know how it goes with the Focusrite. I don't own one as I have a couple of M-Audio cards. But all the guys I know in the biz now use the Focusrite.
Will be interested to see how easy it is to map the 6i6 channels in JRiver. Should work just fine with the Windows and the ASIO drivers.
Will be interested to see how easy it is to map the 6i6 channels in JRiver. Should work just fine with the Windows and the ASIO drivers.
Ha! I remembered the active MTM Meridian speaker that used the KEF B110/T52 and sureynuf there is an MTM that has sufficient cred's to be published. I am going to slip this KEF Toccata under my TV and see what it does as a CC.
Don't know a word of German, but in college I owned a reliable VW bus. So, I am going for it. I don't use all the channels of this receiver/amplifier and you can swap a rear channel for a front bi/amp. How cool is that! So, if I need more "down low" on the CC I will just add an active woofer. It is sort of like cooking with different spices and a fusion cuisine mandate. But none of this has the resolution and refinement of what I am used to on dedicated "reference" systems. It is not unlike being initially impressed with the sound in a friend's new uber import car. And, then, after 15min, realizing all of the substance it lacks.
Don't know a word of German, but in college I owned a reliable VW bus. So, I am going for it. I don't use all the channels of this receiver/amplifier and you can swap a rear channel for a front bi/amp. How cool is that! So, if I need more "down low" on the CC I will just add an active woofer. It is sort of like cooking with different spices and a fusion cuisine mandate. But none of this has the resolution and refinement of what I am used to on dedicated "reference" systems. It is not unlike being initially impressed with the sound in a friend's new uber import car. And, then, after 15min, realizing all of the substance it lacks.
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