Pssst! Erik... over here

[JBryan]

Erik,

I am sure that Coytee was getting tired of our bantering on about full-range drivers and SET amps instead of addressing his amp questions so I thought I'd move the discussion here.

I agree with your assessments in regard to amps and FR drivers. We've had very similar experiences although I do not have any real amp-building experience as you do and I profess that I am blissfully ignorant when it comes to the mechanics and theory associated with acoustics and electronics.

"I used to use a handheld measuring tape to measure the width, height, and depth of the soundstage of my system, but that has gotten more complex now that we have a surround system. I just hold up the measuring tape against the 'sound' until it stops on each side, top-to-bottom, and front-to-back!"

Sounds like a good way to dial in the system. I've found that setting speakers - especially horns in a equidistant triangle with the listening position is a good starting point in my room. My right speaker is in the corner and therefore, its position is fixed aside from minor adjustments. The listening position can move around a bit (I have a couch) but I try to have the 'sweet spot' at its center. Having 2 fixed points, I take a spool of thread (one that doesn't stretch) and affix one end dead center on the top edge of the Khorn (Velcro really comes in handy). I place a weight on the couch approximating where my head would be and attach a stick or pencil in its center. This has to be pretty secure to withstand the tension of the thread.

With the thread pulled tight, I stick a piece of masking tape where the thread meets with the pencil and then mark the exact point of the apex. I then run a length of thread back to the same spot on the right Khorn. I should now have twice the length of thread with the center point marked.

I can now use the 2nd length to find the approximate distancefrom the listening position to the left speaker and finally use the original run of thread from the right to left speaker to check that it lands on the same point. If not, I mark the new spot on the edge of the speaker and then its just a matter of adjusting the left speaker so that both points match up.

I then outline the edges of the speakers on the floor with duct tape and use them as a reference as I move the speakers around to get the best image and soundstage. If I get too carried away or confused, I can put the speakers back in their original positions and start adjusting again.

Its actually quite a crude way of going about it but it works for me.

Have fun, Bryan

[Speedball]

Nothing wrong with going a little....errrr, way overboard on perfection....

......your avatar reminded me of this picture......

[JBryan]

Ahhh... the mighty Avantegard UNO - a very well regarded speaker. I've heard them a few times and while they certainly have their advantages (very quiet), I never considered reaplacing the Khorns with them. I do think the UNOs are the most coherent of the AG offerings but I still couldn't get beyond the bass module. It goes very low - an obvious benefit but the sub sounds like its a separate unit (which it is). The TRIO must be nice at that price but it needs a HUGE room to come together. Standing 15' away, I could discern each driver - and the subs were still obvious.

Still, I wouldn't kick 'em out of my house ;-{)}.

[JBryan]

Erik wrote...

"Certainly ANY choice of amplification is subjective, otherwise there wouldn't be any disperity or difference of opinion among music listeners. The on-going 'sketchy' area that I perceive has to do with proclamations of one kind (high power or low) being inherently better than the other."

Absolutely... Somewhere along the way, I realized that there is no one ultimate system and each choice comes with its own array of drawbacks. For me, its a matter of choosing which compromises to accept and the goal then becomes a matter of whittling away at those drawbacks until I am satisfied (which I'm told rarely happens before hearing loss sets in or the wife puts her foot down.).

Bryan

[garymd]

Hey Bryan.

Are those the khorns I saw at your house? One of these days we need to get together. I'd like to hear your latest experiment and I have a few new toys at my place.

Shoot me an email sometime.

- Gary

[JBryan]

Hey Gary,

"Are those the khorns I saw at your house?"

Yes.. those are the ones. Well, the bottom of them at least. We definitely need to get together. I can't believe that we're less than 30 minutes apart yet only manage to get together a couple of times a year - if we're lucky. I still have your albums that I should return before I lose them in the stacks and I've come across a few new tunes I think you'd enjoy.

Let's make a plan to get together between the holidays. I'd really like to hear your "new toys", check out your jazz and see how your system has progressed.

Have a good holiday and I'll talk with you soon, Bryan

[Erik Mandaville]

Bryan:

You're right -- good idea to move this discussion elsewhere. Bryan, I wasn't really serious about measuring the the 'size' of the music with a measuring tape Just my lousy sense of humor. I sometimes find it funny how professional audio reviewers in the magazines might desribe, for example, music extending at least three feet to either side of the speakers, and with a literal sense of humor imagine them trying to make that measurement with a tape measure. I also like it when a reviewer might make a reference to something such as, "The speakers were so transparent that the original intent of the artist was clearly evident." Well, that's fine, but without having had the opportunity to talk with the artist about his or her objective/s, how do we know what the intent really was? Maybe it was just to throw something together (and give the album a 'catchy' title) to help pay off the remainder of the mortgage! I've wondered about the same thing in relation to the last couple of albums Genesis put out. Yikes, what a far cry from the kind of work they did during the Peter Gabriel era and shortly thereafter.

In any event, setting up the system with care as you do does make good sense. With juggling seven speakers in our room, it can get challenging, but one thing I've become aware of with listening to surround music is that speaker placement has become maybe a little less critical than it was when we were in 'stereo-only' mode. I have a small pair of dynamic driver monitors that I made ten years ago that can project very precise imaging, but they can't or don't 'load' the room the way the horns do. We still have a very obvious front stage with the two K-horns and center La Scala (borrowed from a friend), but I guess the compromise we made involved a trade of sharper stereo imaging for surround sound's sense of space and envelopment. I remember going to a hi-end audio store here in Houston years ago, where I had the chance to listen to two giant wall-panel-like electrostatic speakers (can't remember the brand). Those things had such an incredible and involving sort of sound, but they didn't image particularly well and bass response dropped off quickly.

Recently, so that I can make better use of the dimensions of the room for the surround speakers, we moved the Klipschorns back to the corners of the shorter front wall, and angled the cabinets outward. And this brings me (I knew I would eventually get here!) to a question I wanted to ask you: I like the false corners you made for your Klipschorns. From what I can tell, you cut two large triangular sections of (5/8 ply?), and used the dimension of the height of the bass bin for the two other large pieces that form the false corner vertical walls. Is this close? Also, did you screw the top and bottom sections into the top and bottom of the cabinets for greater rigidity? I'm interested, because it may be that we leave the K-horns on the shorter wall for some time. Without a subwoofer, bass response is good, but obviously not as good as when the speakers are tightly placed in true 90 degree corners.

Erik

edit: I looked again at the wood, and it appears it might be full 3/4" plywood. That would be good, but I don't think I can manage the weight of that stuff right now. Maybe a down the road a bit after my back fully (hopefully) heals.

[JBryan]

"I wasn't really serious about measuring the the 'size' of the music with a measuring tape Just my lousy sense of humor."

Well then... er,...nevermind.

"...Maybe it was just to throw something together (and give the album a 'catchy' title) to help pay off the remainder of the mortgage! I've wondered about the same thing in relation to the last couple of albums Genesis put out. Yikes, what a far cry from the kind of work they did during the Peter Gabriel era and shortly thereafter."

There was a Genesis AFTER Peter left?! How'd that work out for 'em?

"With juggling seven speakers in our room, it can get challenging, but one thing I've become aware of with listening to surround music is that speaker placement has become maybe a little less critical than it was when we were in 'stereo-only' mode."

A 7.1 system anchored with Khorns & La Scalas must sound scary good! My wife wouldn't allow my behemoths out of the basement so we have an Atlantic Technology setup. Even then, I'm only set up for 5.1 with the 2 side-surrounds still in the box somewhere. I didn't have too much trouble setting it up - the processor lets me enter the distance to each speaker and it adjusts the attentuation accordingly. I use a SPL meter to balance them out. Seems pretty straight-forward but then, I don't watch many movies so I don't pay that much attention to it.

Have fun, Bryan

[Marvel]

Erik,

Have you had a close look at TigerwoodKhorn's cabinets? His are made

similar, I believe, but the left and right corners are angled back from

the Khorn front panel a little bit. The look nice that way. As I

recall, he said the improvement was still good. Maybe, if he sees this, he could post some other pics of his work.

Bruce

[JBryan]

Erik,

The false corners are made up of 2 4'x8'x3/4" panels - one of birch ply and the other of MDF. I simply cut them in half and screwed/glued them together with the birch face in front. I also sandwiched a sheet of Dynamat-like damping material in between the 2 panels to absorb some vibration.

They are rather heavy but I didn't have the space to make the studded FC shown in PWK's Dope From Hope and I'm still able to slide the speakers around without too much strain. When I rap on them, they have a duller thud than the Khorn cabs so I figure they are bona fide.

The top and bottom are screwed to the panels and I used corner braces inside for extra rigidity, I screwed the 4 braces into the FC and used wing nuts to tighten them to the bass bins. If you notice, I used the existing screws and wingnuts that were used for the screens to tighten the braces. I screwed the 2 panels together where they meet in the back and used a piece of hardwood along the inside seam for extra strength.

I have installed screws to secure the top to the BB - once again utilizing the existing factory-installed brackets but I am reluctant to tighten them until I am finished playing around as they will make it difficult to pull the BB out of the FC. I did not fasten the BB to the bottom but the fit is very tight and requires an effort to push the BB in so I hope that is enough to keep the bottom snug.

My goal was to attach the FC as securely as possible without making any changes to the BB - no extra holes, brackets or screws. That way, if this doesn't work out , I can revert back to the original Khorn and no one will be the wiser - deniability may be important here. The only alteration I did was to remove those little caps Klipsch uses for feet - but not until after I had scratched one of the bottoms enough to require another sanding and coat of Tung Oil. Aside from keeping the BB stock, I wanted to be able to disassemble them without too much trouble, otherwise, they wouldn't fit through the doorways and would have to convey with the house if we moved.

Much like the difference I heard with the original FC I built a few years back, I noticed a significant improvement with these versions. Closing the BB off (top and bottom) seemed to give the bass more authority and 'Thump' and I'm sure the braces contributed as well. While I'm sure that these would sound better if I were to glue and screw all the pieces together, I just can't make the commitment.

Have fun, Bryan

[Erik Mandaville]

Bryan:

"The top and bottom are screwed to the panels and I used corner braces inside for extra rigidity, I screwed the 4 braces into the FC and used wing nuts to tighten them to the bass bins. If you notice, I used the existing screws and wingnuts that were used for the screens to gtighten the braces. I screwed the 2 panels together where they meet in the back and used a piece of hardwood along the seam on the inside for extra strength. "

Ok, I see now. That's a great idea using the wing nuts as a mounting point. The work you did really does look robust and strong -- something I think would be especially important in our case. We have the system on a suspended wood, second story floor, and have had some strange room-mode issues in the past. It's really nice to be able to sit back from the La Scala and klipschorns, but having them on the shorter wall does seem to have influenced the bass response a bit. Like you, I have been experimenting with the amount of toe, and it seems that angling the cabinets so that the line drawn from them crosses just slightly in front of the listening position sounds best. A laser line for that sure could be helpful! Maybe I can get my wife to stand behind the cabinet and shine a flashlight at my listening chair![] Thanks for taking the time to describe how you went about this, Bryan.

Bruce: That's right, I had forgotten about Tigerwoods FCs. As I remember, he also had done a very good job with them. I'm just afraid to start drilling into the bass bins for this, but guess I don't really have to.

Erik

Thanks again for this information