Center channel with K-horns! Wow!

[Seadog]

I use a 99B for my derived center (Cornwall) with the 299D for my mains (Cornwalls). This works very well using the derived center line out from the 299D. Before I had the Scotts, built a minibox (line level) and used one side of an HK430 for the center amplification with another HK430 for the R and L. I usually run the center about 5-6dB below the mains. To me, the derived center enlarges the optimal listening zone in the room (this could be somewhat due to the center being 4 feet above the mains). For anyone listening to 2-channel who has a good center speaker available, I would recommend trying the derived center. My setup is multi-functional, I use A/B selectors to switch from SS HT to tube 2-channel.

[3dzapper]

Shawn, Thanks. Send it off to Erik, I'm a tinkerer, I like this stuff.

Someday, I'm going to breadboard a 6922 summing circuit for a center channel output from my Blueberry. There is never enough time in the day when you are retired.

First you have to ponder for a while what you are going to do today. Then you take a few minutes to do it. After that you must take time to admire what you have done and the day is shot!

Rick

[edwinr]

----------------

On 11/25/2004 9:51:58 PM DeanG wrote:

I do wonder about all of the people that have migrated from HT back to 2-channel -- there's plenty of them out there.

----------------

...I'm one, Dean.

[Erik Mandaville]

Shawn:

I am curious to try that -- thanks again! You needn't hurry to get it out early next week, though. I think I would like to spend some time with how things are right now, become familiar with the sound and characteristics of this new sound, and then be in a better position to make judgements on the differences between any changes I make. If there is STILL room for improvement over what I discovered yesterday, I am absolutely open to that!

Dean: My Klipschorns area also now on the shorter wall, which places the tweeter and midrange horns closer together, too. What was interesting to me was that even in this application the third speaker on an independent amplifier was, for us, a marked improvement over stereo -- and I have LOVED stereo for years.

You made a statement about those who have tried multi-channel listening, and ultimately decided to return to more traditional stereo. In my opinion, the significant thing about that is that they, as edwin mentioned, felt free to make the choice and are now enjoying the results. What matters is that they like what they have, not whether their individual systems have two speakers or 27. I am not saying the 3 channels will be an improvement for everyone, but I will say that it's something that can be approached as an experiment with an open mind. There isn't any law that I know of that says, "Once you drift beyond the time-tested realm of two channels, you will never again be allowed to return!" All someone has to do is try it. If it doesn't work, there was still something to be gained from the experience -- the education and knowledge that, as far as that person's preferences and tastes are concerned, listening to three or more channels isn't as GOOD as L/R stereo.

There will always be differing opinions on ANY topic. For me, 3 channels has been an improvement. That doesn't make me any more RIGHT about what's best than someone else who prefers the simplicity of one speaker on the left, one speaker on the right -- and that's all! It's not a competition, and somone can't be wrong about what they have decided as being 'right' or 'correct' for them.

Erik

[Deang]

Can't you just let me be pig-headed and small-minded, I worked very hard to get this way.

Jim Bongiorno evidently likes the three-channel set-up as well:

http://www.ampzilla2000.com/trinaural.html

[Erik Mandaville]

LOL! if that's what makes you happy, no problem at all at this end!

I've read about the processor on a couple of occasions, Dean -- thanks for including the link. I honestly don't know what prompted this interest in a center channel! I can't remember who posted above how the third speaker really seemed to broaden and even out the image, but I find that, as well. It almost behaves like a sort of sonic spackling compound that very nicely fills gaps in the image I didn't really know existed until comparing the sound with and without the third speaker and amp. The sound just sort of becomes much more limp and lifeless when the center speaker is turned off. again, the strength of its presence in the overall reproduction can be made more or less obvious by adjusting the output. It really does just VANISH, and has not seemed, at least so far, to do anything negative at all.

Another characteristic of this seems to be much better off-axis response. Sitting off to one side and listening while others were playing video games (video sound off -- they preferred the music, too!) did not have nearly the effect that it used to. I find horn speakers in general, but specifically both my Lowthers and K-horns, to be pretty directional. They do not have the same horizontal and vertical projection that other speakers I have made using dome tweeters and dynamic drivers. This is where the center channel seems to really be adding something special. I still much prefer a central listening position, but the image seems to remain much more intact when listening off-axis.

So now I'm wondering: Once the Heresy goes back home, I've got two Lowther horn speakers that might be interesting to experiment with. There is no doubt in my mind that for me a third channel is better. I am going to use one of them (at least for now)as the center channel, but what if I put the other Lowther BEHIND me, driven by the other Moondog, which would in turn be controlled by a second minibox!? It would be further to the back than the center channel is to the front of me, and I could attenuate it so that there is a very subtle ambient effect. It would be barely noticable. There is even another cabinet I have been very interested in trying, called the 'Ace,' that is intended for non-directional use of Lowther drivers. It's a very simple design, and could be built in a day. The 'Ace' might do something very interesting!

At live music events, sound has always seemed to me to come from all over the place. It must bounce off walls, ceiling, and floor throughout the venue before it hits the ear. Maybe something coming in a very subtle way from BEHIND the listening position would make for an even stronger illusion of being in the presence of performing musicians. Maybe it's worth a try!?

Erik

[maxg]

Erik,

Somehow I think you are kidding with all of this...

You talked of adding a sub first. Then a centre channel and now a rear!!

Lets call that 4 channels plus 1 for the sub, or 4.1 for short.

You'll need something to introduce a delay for the rears I would guess - probably have to be a variable delay to account for your room size - unless you build something specific.

Plus I think you will find it works better with 2 speakers at the back - lets call that 5.1 (ring any bell(e)s?).

Whilst you are about it - add another centre channel for the rear and 2 more speakers mid way between rear and fronts and we may as well double up on the sub.

That makes 8.2 unless I lost count. I think I see an SACD player in your future too.

Of course doing this with all heritage might put the squeeze on both your room and your budget.

Might be better to jack in the KHorns and Heresy and go for a sub / satelite system - at least all these speakers will fit in. Klipsch do a number of these systems.

Also adding endless low power SET monoblocks will get confusing - and may not be easy to match to a surround sound processing pre-amp. Yamaha do some nice big surround sound amps that will let you adjsut the level of the sound coming from each speaker down to -10 dB last time I looked.

Should be great for movies - just not sure about the music....

[Erik Mandaville]

Hi, Max:

You are right! A subwoofer is going to be tried, and I am 100% serious about trying a rear channel. I have to say this again: Any change that does not seem to work well does not have to stay that way. Just because an experiment is being done, does not automatically mean that I am stuck with the results. At this point, I can say without doubt that a third channel is for keeps.

I have learned enough over the years to make certain provisions for impedances mismatches or imbalance, and with a little work and effort, there is not reason why a rear channel should not work effectively. Whether I like the way it sounds is entirely different from making it work.

[Deang]

So much of our two-channel experience and work involves getting the tone right. I like your little boxes because they are so simple and straight forward -- which I think plays a big part in keeping the nice tube/horn signature intact. Once you go to digital processing, you mind as well forget about that.

[sfogg]

Erik,

" I think I would like to spend some time with how things are right now, become familiar with the sound and characteristics of this new sound, and then be in a better position to make judgements on the differences between any changes I make."

The Lexicon can do just a derived mono center without removing that info from you L/Rs very similar to what you box is doing now but with the addition of allowing time alignment with the center to your mains. It can also if desired steer out some of that info from the L/Rs and send it to just the center channel and you can vary how much or how little it does of that. There are numerous ways you can control how much contribution the center gives to the playback.

If you want to try rears (and sides if desired) it can do all that too, as well as handling the crossovers to a sub.

For more details on this check out this booklet:

http://www.lexicon.com/products/download-details.asp?ID=12&FileID=44

" I still much prefer a central listening position, but the image seems to remain much more intact when listening off-axis."

This is because the center channel is anchoring the image in the center of the room. Instead of needing to be located in the sweet spot to get a phantom image you have a hard speaker reproducing the central material. That will help reduce the imaging shift for off axis listeners. This gets even stronger when you actively steer material to the center and remove some of it from the L/Rs.

" Maybe something coming in a very subtle way from BEHIND the listening position would make for an even stronger illusion of being in the presence of performing musicians.  Maybe it's worth a try!?"

It is absolutely worth a try.

Max,

"- add another centre channel for the rear"

A rear center speaker is psycoacoustically a bad idea. Human hearing can mishear a center coming from directly behind us as appear to be coming from in front of us. This rear to front inversion is pretty much the exact opposite of what we want to accomplish with the rear center speaker. It is better to have two widely spaced rear speakers and to feed them stereo material to try to avoid this problem.

" I think I see an SACD player in your future too."

He has an SACD player already.

Dean,

"-- which I think plays a big part in keeping the nice tube/horn signature intact. Once you go to digital processing, you mind as well forget about that."

Which digital processing have you tried?

Shawn

[maxg]

Shawn,

As you can tell from my posts my knowledge of multi-channel setups is scant to say the least.

But I thought that 6.1 was the addition of a rear centre channel - maybe I am wrong.

[Daddy Dee]

----------------

On 11/25/2004 10:19:44 PM DeanG wrote:

Well, with my false corners I sure as hell don't have room for a LaScala in there -- but I could probably stack the Heresy's.

In PWK's biography, there was a sketch of a three-channel setup using TWO monoblocks, and making use of the different taps to stablize the impedance. Has anyone here seen this besides me?

----------------

Dean,

Dean you are right. Father Bill explained this to me and I'm never quite sure I have the "common" and "differences" issue correct. However, as I remember Father Bill said this was PWK's first solution for a derived center, but the center was derived by combining the "differences" of L and R in the center. The minibox solution, which he came to prefer combined what was "common" between L and R.

I know I've been corrected (helped) on this issue before on the forum, but for some reason this requires mental gymnastics for me that I haven't mastered. I'm not sure which one is "summed".

Whichever is correct, I am for sure that Mr. Paul preferred the minibox to the earlier solution.

[Erik Mandaville]

Shawn:

That component is sounding more interesting all the time. It's difficult to be in the position to afford another component right now, but that has nothing to do with the fact that it may be exactly the thing we would BOTH need and want (sometimes those two aren't always the same!)

So, lets keep that open as a possibility.

Max:

My knowledge has been totally scant, as well. That's precisely why I'm trying this -- to reduce my ignorance for myself and to get first-hand knowledge and experience. What better way of learning about something than to jump in and try!?

Erik

[sfogg]

Max,

"But I thought that 6.1 was the addition of a rear centre channel - maybe I am wrong."

No, you are correct that 6.1 material has a back channel in it. The optimal setup for that back channel info is to play it back across two rear surround speakers in a 7 speaker setup.

Many don't do that and instead use a 6 speaker setup though for whatever reason. However that rear center speaker can cause the inversions I mentioned for listeners located on its axis.

Shawn

[sfogg]

"and I'm never quite sure I have the "common" and "differences" issue correct."

The 'difference' signal is basically the material that is 180 degrees out of phase between the L/R speakers. This is what you get if you connect an amp (EDIT: should say speaker) across both positive terminals. I think PWK originally used this for a center and then changed his approach on this. Typically that is considered the surround info.

The 'common' material is basically the material that is mono and in phase with each other in both L/R speakers. That is what you hear as being a phantom center channel in 2 channel playback so it makes sense to steer this to a center channel.

If you have something like the Stereophile test CD (or anything with a phase test) listen to that. The in-phase material is the 'common' signal, out of phase is the 'difference' signal.

Shawn

[sfogg]

Erik,

If you want to borrow it I'll send it out. I'm not currently using it as it is intended for my upstairs system which I just haven't gotten around to installing yet. My wife wants to rearrange that room first then I'll hook up the system so until then it is just sitting on a shelf not doing anyone any good.

" It's difficult to be in the position to afford another component right now, but that has nothing to do with the fact that it may be exactly the thing we would BOTH need and want (sometimes those two aren't always the same!)"

If you were to decide you liked/needed a box like this one (mine isn't for sale) you are at least in luck that because it is an older digital processor its current market value has dropped dramatically. I bought the same Lexicon the first time around (when these were current models) for literally 10x what I bought this used one for.

But maybe you will hate it and it won't matter either way.

Shawn

[Daddy Dee]

----------------

On 11/26/2004 11:02:53 AM sfogg wrote:

"and I'm never quite sure I have the "common" and "differences" issue correct."

The 'difference' signal is basically the material that is 180 degrees out of phase between the L/R speakers. This is what you get if you connect an amp across both positive terminals. I think PWK originally used this for a center and then changed his approach on this. Typically that is considered the surround info.

The 'common' material is basically the material that is mono and in phase with each other in both L/R speakers. That is what you hear as being a phantom center channel in 2 channel playback so it makes sense to steer this to a center channel.

If you have something like the Stereophile test CD (or anything with a phase test) listen to that. The in-phase material is the 'common' signal, out of phase is the 'difference' signal.

Shawn

----------------

Shawn, thanks. Makes sense.

[Erik Mandaville]

Shawn:

That is very generous of you. I very much appreciate your willingness to share it with me. I will take very good care of it. I'm very much a beginner with the concept of using more than two channels, so would need to study its features and user guidelines. I would want to read as much as I could about how it works before I actually tried it out. Do you happen to have an owner's manual for it? Perhaps an on-line informational link?

Thanks again!

Erik

[sfogg]

Erik,

Makes sense to me. The link I gave you earlier gives you the thinking that went into the product. It gives some good info on surround sound and reproduced music and a general ideal of how we hear sound in a hall. It is well worth reading.

The instruction manual is at:

http://www.lexicon.com/downloads/downloader.asp?File=dc1/DC-1_V3_Owners_Mnl_Rev0.pdf&fileID=30

A quick reference guide for the menus is at:

http://www.lexicon.com/downloads/downloader.asp?File=dc1/DC-1_QRG_ac3_Rev1.pdf&fileID=37

It looks a little scary when you see it like this but the unit has a very well structured user interface and is easy to use and will make sense when you get it in front of you and start using it. If you have questions on anything after reading any of the above just ask and I'll try and clear it up for you.

If you want to get into serious details on surround sound and hall sound and things of that nature check out this page.

http://world.std.com/~griesngr/

This is the home page of Dr. David Griesinger who is the head researcher at Lexicon and the designer of much of its music processing abilities. Many of the papers there are pretty hard core presentations to AES and things like that so they can be overwhelming at first.

If you want some tricks and tips on the unit just ask away and I'll give you a bunch of them. It might make sense to wait until you have the unit before I do that so you can try what I'd suggest right then and there. The other thing that can help is after you get it if you tell me what you like or dislike about the sound you are getting I can probably suggest settings to change to alter the presentation. It is very flexible in that regard to really tune it in to your tastes.

Happy reading....

Shawn

[oscarsear]

curiosity here. Y'all been discussing heritage speakers in this configuration. The RC-7 will accept independent R and L channeling. What about bi-amping on of these so that left and right remain dedicated but with a centralized output (or am I missing the point all together)?