What about Jubilee Khorn ?

[BerndH]

While i found it very honest to create a 2-way high efficiency horn system, it is enormous work. The parameters size, efficiency, bandwith, directivity, frequency response are hard to combine in such a system.

Like Gil commented the comparison between the Jubilee and the K-Horn, the K-Horn was better in the highs. So i find the engineers have a problem with efficiency and bandwith. Crossing over at low frequencies means a big compression driver, mostly 2" drivers. These drivers fall off very early off axis, about 8 to 10 kHz. Look at the KPT Jubilee: A 3-way system with big mid horn and tweeter. Why there and why should a domestic, but high efficiency system work in another way?

Bernd

[sunnysal]

I don't know if anyone posted the jubilee picture so here it is...

[Colin]

It really does depend on what kind of affect you are looking for. The problem with the accurate and flat low frequency response of the classic big ole corner horns is that they do NOT have enough mid-bass punch for movies and some forms of music. They are wonderful for orchestral music, where the low booms of the tympani contrast to the sweet sounds of the piccolo and triangles. But todays techno and action movies require theater-like whallops of bass.

In the excellent article, Subwoofers Under the Christmas Tree, December, 2001, by Brian Weatherhead, he compares not only the leading Velodyne grand-daddy sub-woofer, but also the Internet-only SVS tubes and the punchy Klipsch KSW and RSW series. The article not only compares how the subs sound and shows their frequency response curves, it also reduces their price to output ratio to something he calls a shake value. Very interesting stuff:

1. If you want the mid-bass punch for movies and drums, then according to the wonderful comparisons and charts provided by Weatherford, the powerful Klipsch RSW series would be the best choice. It gives more output in the 83 to 121Hz mid-bass range than any of the other subs compared. It also has the second most output, next to the SVS tubes, in the low 24 to 34Hz area.

2. If you seek the tonal accuracy and mid-range balance that comes from a truly flat frequency response, then the only commercially available sub-woofer that can fill out the big ole Khorn bottom-end is the SVS tubes. They are the only subs which go deep enough to make a difference in the low-end bass response. It clearly has the most output in the very deep 13 1/2 to 45 3/4Hz range.

3. By the way, the author bought both the SVS and the Klipsch RSW sub-woofer.

I have heard the SVS tubes with conventional loudspeakers, and while I do NOT have a RSW series sub, I do have its ill-fated Klipsch LF10 precursor. The other problem with exceptionally low notes is that you hear them better in other parts of the house, but NOT as well as in the semi-open listening room. The low frequency extension of my big ole horns resounds throughout most of my humble abode, but I dont catch much of this while I am in the same room.

The low frequency wavelengths extend throughout the house better then they do in the listening room. In this regard, the benefits of the deep SVS tubes are nowhere near as apparent as the mid-bass punches of the LF10. You hear the mid-bass punch more than the low notes. While I have long been an advocate of the deep SVS tubes, as more suitable matches to the low frequency depth of the Khorn, I must admit that today I would go for the mid-bass punch of RSW type subs, especially for rock n roll and movies, first before trying to reach for that first low octave.

[Champagne taste beer budget]

Since the topic of room size is being thrown around, I though this would be as good a any a place to ask about it. I remember seeing something not too long ago about the "ideal" proportions for a listening room. Since I have some latitiude in the room layout downstairs in our new house, what would anyone recommend for diminsions? the ceiling height is already set at 8', and the portion of the house I have to work with has a max lenght of 26 feet, width optional. I would have to assume you're better off to design the correct room, then work with your setup, than design for one setup, knowing that it will, in all likelyhood, change many times over the years.

I'd also like to note how impressed I am with the knowledge, both practical and theoretical, that so many members of the board have on accoustics and sound. Kinda glad my tweeter blew, or I would have never found the wealth of information this forum provides.

[sfogg]

Colin,

"then the only commercially available sub-woofer that can fill out the big ole Khorn bottom-end is the SVS tubes."

Nahh, there are other commercial subs that can do that and more. Of course they cost a lot more too.

Check out the sub talked about in this thread:

http://www.avsforum.com/avs-vb/showthread.php?s=&threadid=272320

It is horn loaded as well. ServoDrives ContraBass would certainly work too.

Shawn

[Ray Garrison]

C.T.B.B. -

I would strongly suggest that you engage the assistance and expertise of a local high-end home theater dealer who has the necessary expersite and resources to help build the room.

The dimensions are important, but so is construction methodology, materials, and a host of other factors.

[Champagne taste beer budget]

That sounds like a great idea, however... My beautiful, loving, understanding wife does not share my enthusiasm for music. If she can press a couple buttons on a remote and music comes out of the speakers, she's happy. I have come home before to find our 3 yr old daughter had been adjusting the tone controls on the system and my wife really wouldn't notice a difference until I pointed out that the bass was at max and the treble at min. Since we are already considerably over budget for the house, I don't think I'd be able to talk her into a grand, or more probably, for someone to design a listening room for me. A nice thought, but probably not in my plans at this time.

[formica]

I'm guessing you are wondering about the magical or golden room dimensions you often see floating around on the net and were even mentioned in Klipsch's Dope From Hope. They aren't absolute ratios as some variances can sound well too. You should head over to the Klipsch Architectural forum ... and read up on some of the other posts. Like you said, there is a wealth of info there.

As for the "golden" room ratios (height : width : length) they include 1.00 : 1.14 : 1.39 or 1.00 : 1.28 : 1.54 or 1.00 : 1.60 : 2.33 but many variations from that work well too. Given that you already have a fixed height and length you can work from that. Note that these figures are looking at interior finished dimensions.

Later...

Rob

[Champagne taste beer budget]

Thanks formica, those were the ratios I was looking for. Does anyone know if there is a preferance of one set of ratios over the other, and why? I would guess it would have something to do with bass frequency cut off points? Then again, maybe not. I went over and read the thread on mOON and arttos, amoung others, work on mOOn's listening room. Maybe, just maybe, if I quit my job, went to school for a couple years of engineering, and spent all my available waking hours reading technical papers on the topic, I'd know 1/10 of what some of you can discuss as easily as I can tell you why your ECM needs a MAF, TPS, ECT, RPM and ACT signal for a basis to determine where to put your IPW.