JohnA

Peter, Ed, The idea is to build a J-shaped (L-shaped?), unfolded bass horn with the mouth against the floor, and place the HF section on top of that. The woofer would fire downward, its back air chamber would be between the HF section and the bass horn. I'd hope to make the footprint about 2' x 2' and have the left and right sides parallel. I'd try to vary the front and rear to achieve expansion. Since it would be tall, stability will have to be addressed. The killer for this whole project might be cost. If I can buy La Scalas for the same price, why bother? Even Cornwalls on stands would perform the way I want. John

ED, I've got your spreadsheet. Thanks! I have a drawing that shows the slot the La Scala woofer fires through (throat?) is 13" x 3". That would give a compression ratio of 3.4. Is that accurate? I can't reach that far into the bass horn and it too much trouble to dissamble one right now to check. If so, I can build a 45" J-horn and set a La Scala top end on it and have a stunning rear surround. Your calculations are for a square horn, is rectangular expanding to square acceptable? It is most important that the area expand exponentially for the horn to have proper performance, is it not? John

I think 50 to 60 Hz is plenty. All I think I need is a pair of 6' tall La Scalas. John

Gary, Al has a line on good components and a nice upgrade to the T2A autoformer. I'm sure the woofer could be run without an inductor, but PWK must have discovered it blends better with the mid using the inductor. A single element in a crossover gives a 6 dB/octave slope, not much, so the speaker depends on the the natural rolloff of the bass horn at higher frequencies. E-mail Al and be sure to orient the inductor and autoformer at right angles to each other to limit the influence of one on the other. John

Ed, I'd like to have the spreadsheet. I've got a cabinet maker in mind for the building. I need to see if the size will work out, though. The La Scala bass horn is pretty short, so I ought to be able to do it. John

I'm not having the luck I expected on ebay finding something for the rear channels, so I want to see what I can gin up myself. I was thinking about a K-33 firing into a J-shaped horn about 5 feet tall and the mid and tweeter on top. Maybe the horn would need to be a "C" to get it long enough. To find out, I need the design equations and a drafting board. I just noticed the new star. John

I'll keep looking, but I didn't find anything last night. John

How is the shape of a horn and the curve of its sides calculated? Is there a good design manual for horns? I have a design in mind and I want to calculate the size and shape required. John

Look at this post: http://www.klipsch.com/ubb/Forum1/HTML/000419.html John

I got thi image off of E-bay, but I've seen it fairly often elsewhere on the web. John

This is a picture of the group of Klipsch speakers I mentioned in another section. I recognize the K-horn , Belle, La Scala and Cornwall. One of the two in the front is a Heresy; what's the other one? This is an old group picture. John

We are waiting with baited breath! John

The discussion, "Modernize the Klipschorn ....", brought out a point that the K-400 throat and driver may be mismatched. It got me thinking about my own La Scalas. I bought them used and I am probably the 3rd owner. If I remove the K-55-V I have a red rubber washer in the throat and its i.d. is less than the i.d. of the horn and less than the o.d. of the screen protecting the phase plug of the -V. I'm pretty sure my speakers were monkeyed with before I got them, I just don't know how much. What size washer is correct? Shouldn't its i.d. be a smooth fit with the i.d. of the throat? John

JW, Can you scan and paste a sketch of the tweeter filter you recommend be cut? I think my spare Type AL has it, but I'm not sure and your description of "eliptical" throws me. John

I'll give you $200 for both of you retired K-horn uppers; if they're relatively unmolested. Seriously! I have a rear channel design in mind. John