coolhandjjl

Regarding tweeter height placement, isn't there some rule about placing the centers of the drivers within 1/2 wavelength of the x-over point? 5kHz @ 24dB/oct LR, so roughly 3 cm away? How do you do that with a horn taking up all that space? Or can you mount it a defined distance much further above that 1/2 wavelength? I mounted it far back to time align it.

Now that the tweeter horn can-o-worms has been opened again, whatever happened to this guy? There was a lot of hoopla about it a few years back. DDS CFD ENG 1-90 PRO http://www.usspeaker.com/dds%20cfd-eng-1-90pro-1.htm

Holy cow Bob! The APT-50-2 response curve looks awful. Good thing you locked onto the manufacturer of the original APT50.

Isn't the Crites Tweeter the APT50 also? Looks like the plastic mount is maybe the APT80 horn sawed off?

Just when I thought it was safe to go back in the water!

Thanks for the great comments everybody. I feel like one of the boys now. Now I can safely reveal to the world that I actually like loudness buttons sand tone controls! [:$]

Oak dowels are used to support the gear. I think they go in the blocks 3/8" or 1/2". They droop a bit under heavy loads though. The block ends are stacked onto each other with 3/4" pegs, spaced apart with plumbing fittings. My design makes it super easy to swap gear in and out, mess around with interconnects, and everything gets more than adequate airflow.

It's a Linaeum ET6. Mid 1980's era I think? Mylar dipole, superb sound, lousy efficiency. But it's Time Aligned! [H]

Thanks! I bought a piece of curly/tiger maple, and I plan to add a piece of trim around the front. With some deep amber shellac, it will tie into the fender tweed on the bass bins.

last one

couple of rear shots

and more

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Here we go! You can start to see the humps in a couple of the pics because of the studio lighting, but in real room viewing, it looks smooth.

I'll try to get pics. Nice look with the shiny finish. Mine did not come out as perfectly smooth, but since my finish is textured matte, the humps do not show up unless I take a flashlight and position it inside along the surface of the curve. Ditto again on thick sandable primer. I could have sanded for a year on the bare MDF and still not gotten it smooth. I bought the 8 ohm version of the DE750TN, as I am bi/tri amping with a tube amp for the B&C and didn't want to get caught with an amp that wasn't 16 ohm ready. When I was testing all this out, my only tube power amp was a Peavey full range 50wpc tube power amp with EL84's. It won't drive 16 ohm speakers. I just bought a Dynaco ST35 to be my new mid-range amp with original transformers that are 8 and 16. Go figure. This really is a superb midrange set-up. No resonant peaks, no ringing, no honkiness, seems impossible to encounter lobing. Anyone considering this and is on the fence, jump in, the water's fine!

I bought Dave's Eliptrac 400 in kit form a while back. I assembled it, did rough sanding, and got busy using it with the B&C DE750TN. Absolutely the best midrange combo I've ever encountered. I took the driver off last Friday and did final sanding, and priming. I used Kilz-2, a white latex primer suitable for any top coat. Being white, it also allowd me to see the high spots for additional sanding. I sanded down the 'humps' inside the horn from the seams and glue joints with a better ability to see what was going on. Anyone doing the kit may want to keep glue away from the inner edges. I did wipe out any squished out glue, but with the glue being harder then the MDF, it was a tough sanding job. It is as reasonably smooth as I could expect now. I put on one more coat of Kilz-2, and then a light sand with 220 grit. Then I used Rustoluem Filler Primer, a grey thicker-than-regular spray primer, so it helped fill in any tiny seams or other marks in the wood. A coule coats of that, and a light sand with 220 grit. Smooth as a baby's bottom. I'm letting them sit for a few days to fully cure with all those layers of paint on them. So I don't get bleed-through issues, I have some other Rustoleum spray primer in an iron oxide red color I'll go over the grey primer with. Top coat will be Rustoleum Multicolor Textured in Autumn Brown. The throat takes a bit of care, dry overspray tends to collect there, so it needs to be wiped out when fully dry. Since it's hard to get a good head-on spray angle in the throat, the texture seems to be a bit 'toothier' as a result when compared than to the flare area. Shouldn't be a problem with the texture style finish coat I'm planning to use. I did take the mount off, masked both the mating sides, masked a cricle where the driver goes, and sprayed that separatey. I just didn't know what to expect if I did it all bolted together, paint may crack in the wrong place, may crack roughly, not sure. Dave probably has a method that works best for him.

Looks like you are trying to build a Jubilee. I saw a pic from a guy who put "wings" on his khorn to get it out of the corner. Something like pieces 5' long. I'll try to find it.

No takers?

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I purchased the Eliptrac 400 in kit form. Not as hard as it looks. It is a nice horn, no honkiness, very even dispersion. People here have used the Faital HF200 as mentioned, the B&C DE85TN, and B&C DE750TN all with excellent results. You can't go wrong with any of these drivers mentioned. Don't worry about wattage ratings or running them down to 400Hz or so. Unless you are setting up a touring rig for Metallica, you won't be putting more than a fraction of a watt or so into these drivers. I had tried the Radian 950PB, but it didn't carry the high end on this horn in a two-way configuration. I exchanged it for the B&C DE750TN. For people with a bit more dinero, ALK also recommends the B&C DCM50.

Greg Roberts of Volti Audio discusses the bass of a Jubilee inspired bass bin, a Jubilee, and a K-Horn. They are all winners in his book, with the edge going to the K-Horn. http://www.voltiaudio.com/jamboree.shtml If you have your heart set on the K-Horn, and realize their placement limitations, my suggestion is to find a pair on CL that you can get for cheap, and upgrade them.

That is great question. Do you want to be locked into corner placement only? What if you move and don't have available corners anymore?

A 40Hz wave is about 28', so whether it comes from the center, or wigggles in from the edge, the diff is only several inches, it's inconsequential compared to the total lenght of the wave, right? A 15,000kHz wave is about 1", so if the wave is coming from the edge of a 4" diaphragm, having that bounce around inbetween the diahragm and the driver's exit, now it does matter and it will interfere with some shift in phase causing a cancellation? I think I've got it!

I guess Phase Plug is probably not the right term. Probably more like "slotted horn throat opening" or something like that. But I have seen woofers in horns that fill the areas not exposed by the slot with two pieces of carved out solid extruded insulation so the gap from the woofers cone sections that are blocked via that slot remains constant from the woofers edge to the exposed area. I've also seen wood discs floated over the slots center like a true phase plug. But most of the time, I see the connection between a woofer and a horn is just a plain slotted opening (some quite wide, to almost the ends of the cone, others quite narrow.) Is the abscence of a true phase plug due to the bass wavelengths being so long that a phase plug is not necessary or that effective?

Thanks for the replies. I don't have a K Horn, but I am trying to learn about speaker design.