bigdnfay

Initial flares

Hi All, Got started on my project this week. Got about 24 hours in them so far. Just thought you might like to see the progress. Pics below. Darrell

Bret, VERY NICE WORK! I KNOW you spent several hours on this project. I put together a model about a month ago to get all the angles and lengths of the various parts needed. I calculated the throat opening to be 10 3/4 x 4 3/4. The 10 3/4 is the diameter of the woofers I bought for this project. the 4 3/4 is twice the height of the first leg which I calculate as being 2 3/8. On the model I plan to keep it at that height/width until the second turn up the doghouse. From what I can tell, your drawings are close to what I came up with. I'll sit down with your drawings this weekend and do a comparison. I'm taking a week off near the end of April to build these babies. All my parts have arrived and I'm ready to go. Don't you just love coming home and finding boxes on the front porch...Boys with Toys! Big D

Hi All, Ordered the pioneer woofers from parts express. Recieved them today. They are not as cheesy as I first thought. Even though the surrounds are foam they are surprisingly stiff. I am confident they will do well. Another problem solved. Big D

I drew up those plans and your welcome.

I've looked at the pioneer in parts express and their chart says it's not suitable for sealed enclosuers. I talked to klipsch parts dept. He looked up the pro Jubilee and all that came up was the K-31-E. this is also the replacement woofer for the KLF-30. So I ordered one. It's a poly-carb cone with a foam surround. It's not really designed for flush face mount. It's a drop in from the front. There's a hard plastic ring just outside the surround. Not goot for making a good seal. Big D

http://www.ossaudio.com/hornbackgrounder.htm I read this article and it states a smaller coil is a good thing..faster transients,etc.

I've been looking at the Eminence Kappa-pro 12.

2-12's

Hi All, I hate to beat a dead horse, but I am having a little difficulty locating the right woofer for my Jubilee build. I have talked to a few engineers who said that T/S parameters are not as critical as I thought. To me it appears that at least a few are. For one, the Fs. the parameters listed in the AES paper call for a 19 Hz Fs. Why so low if the horn is only designed to go down to 38 Hz? Another is the Bl, the higher the Bl the driver operates with more authority. I am trying to keep the Re(6 ohm) and Le (1.0 mhy)close to Al's Es700 requirements. I hope this makes sence to everyone, I've been at this for 2 weeks and I don't know if I'm coming or going. I guess the big question is, What are the most important things I should be looking for? Heeelllppp Please, Big D

Problem solved..bought a pair of Altec 807-8 that will mate with the 511b's I have. Al's ES700 is a go. Been very difficult finding woofers with the right T/S parameters and durable surrounds. Probably going to go with the klipsch woofers. Big D

I've been looking at the B&C-82 HF driver. I also want to use the 511b's I already have. The driver has a 1.4 in. throat and the horn has a 1 in. opening. Question...Can the opening on the horn be opened up by 1/8 in. without causing any problems to recieve a 1.4 in. driver. Big D

I think it was mentioned that the woofers from the KLF-30's(K-31-K) were used in a demo at Hope. The woofers used in the commercial units are the K-1080-KP at $125 ea.. Will This work for home use? Big D

Hi All, Finished up the template today. No extreme angles or surprises. Now it's time to gather up the LF and HF drivers. Networks are still a big question. Hopefully Al's ES700 will fit the bill. Does anyone know of a good source for LF drivers? The closest thing I can find with the right T/S is a Pioneer in the Parts Express catalog. I'm not real crazy about using a woofer with foam surrounds. I've looked at several companies but no luck. Any suggestions are appreciated. Big D

I took 3D's advice and read the Bruce Edgar article "The Monolith Horn". It really shed some light on my question. The bends work as diagonal reflectors,hence the narrowing of the turn.The bend in the Jubilee is about 48 degrees,but still effective enough to allow the wavefront to reflect off of the first diagonal reflector to the second reflector with no backward traveling waves. The picture(fig.6)in the article only shows a 90 degree turn. By using a mirror image, it makes a 180 degree bend which is what I think PWK intended. Obviously PWK knew what he was doing.Who am I to question? So it will be built "as is". Once the 2-dimensional model is finished, I'll use a laser pointer and a few small mirrors to check the bends. Sorry about the diagram. Another question. Has anyone had any experience with a B&C DE-900 drivers. This may be a possible candidate for the HF. Big D

3d-Thanks for the info. looking forward to the read. Big D

If I don't seperate the chambers, how about dividing the horn from mouth of the motorboard to the 3 inch turn towards the rear of the cabinet. I don't see any seperation in the last leg of the horn, just vibration dampers. D-man you have a PM. Big D

It was stated that the air chamber is one open area. Would there be any harm in dividing it into two seperate ones? It would add extra stability to the cabinet.IMO I do agree with D-man that the mouths should be symetrical and that this was a "money no object" design.

Thanks D-man.....Lots to think about. Big D

This is how I envisioned the internal workings(from back to front). This rendering has 2 air chambers. To me, in order to have a passive, there would have to be alot of changes. 3 slots or openings would be needed. would it not change the first flare outside the mouth of the motorboard? Does the passive need a flare as well?

I think 2 woofer doors is the way to go. I have another question...Are there 2 air chambers or is the air chamber one open area(top to bottom)? Big D

When I built my k-horns there were several compound cut. From what I can tell there are none in jubilee since all the folds are on one plain. This ,to me, would seem to be an easier build, but I think it will take just slightly more plywood. Big D

My intent was to use Al's 2-3way ES700t extreme-slope network,but I have not discussed it with him to verify that it will work with this setup. I don't know the implications of using dual woofers. Thats better left to the experts. Big D

Klew, I too am planning to use a pair of 511b's collecting dust in my storage room. Having some trouble finding a good HF driver to mate with them. Any good suggestion? Did find a LF driver from pioneer with the right Qts but not crazy about the materials it's made with. klipsch uses the k-1080-kp in the commercial version. Big D

Thanks Chris, I'll take you up on that. Big D