A Bookshelf Multi-Way Point-Source Horn

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Looks good, I have these horns, too. Which speakers did you use? The driver is a screw-on? Any details about the crossover and measurements? Did you try to smooth the throat section a bit? I plan to do something similar, since I now have no use for the horns. By the way, they should be 2380A clones, 90x60 directivity, which conforms with my rough measurements.
 
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Very interesting thread - it is more interesting as the LTH-142 can be bought here easily. I wonder, xrk971, do you have the models for 3D printing the adaptors in this thread? I tried to search, but was not successful. Thanks.

I lost a bunch of things in a hard disk crash a while back. The 3D files may have been in the loss but let me check. Sorry I don’t have notifications for this thread turned on so did not see your question.

So I searched for the largest horn I could buy locally in Slovakia and bought some budget drivers. The horn is some thick ABS plastic copy of the old JBL 2" horn (I don't know which one), sawed off the long throath to reduce the physical distance between the CD and the mids and put a 1" reduction to it. The results are very good even with budget drivers, it has greater depth by the listening distance and goes down to 60Hz.

Dberecz,
Very nice work! I like the construction and final color. Is it a passive XO?

78040042_2885958634768443_5793897224307998720_o.jpg
 
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Looks good, I have these horns, too. Which speakers did you use? The driver is a screw-on? Any details about the crossover and measurements? Did you try to smooth the throat section a bit? I plan to do something similar, since I now have no use for the horns. By the way, they should be 2380A clones, 90x60 directivity, which conforms with my rough measurements.

As I have no RTA and measurement software, I will be able only to give you the freq. response measured by iPad (it is quite accurate). Mid speakers are BS acoustic PL6 and the comp. driver is Master Audio DR7. I also have a pair of JBL 2412H and Master Audio DR8 drivers to try. The driver is a 1" with 35mm thread, there is an adapter that you can attach anywhere, it is called ridriv.
What do you mean smooth the throat section?
 
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I meant if you mounted the adaptor directly or if you made some smoother transition from the round exit to the horn.

I think you could export a sweep from REW and then record it by iPhone and import back to REW for analysis. Or the measurement mic from Behringer works - not calibrated, but nevertheless it can tell a lot. Feel free to PM me if you would like some more info about REW and how to measure/(klidně mi napiš zprávu).
 
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You are in luck, I found the files!

Here are the STL files for my version of the Xbush speaker. LTH horn wall adapter for woofer mounting, 6-hole drill template for horn wall, DC200 cone volume fillers, and 3 sizes of SB65 throat adapters.

Enjoy!

Horn wall adapter:
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Throat adapter:
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DC200 cone volume filler:
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Download a copy of REW, use built-in mic on iPad. Or get a USB mic. There’s no way a speaker like a synergy can be properly optimized without a proper RTA and mic. There’s more than just frequency response. The level of effort you out into the speaker deserves at least a $40 mic and free software.

I have build a measure mic, these does well.

regards
 

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Synergy vs standard 2-way using same components.

I just ordered 2 18 Sound XT1464 horns and 2 SB65WBAC25s. We know based on Bushmeister and XRK971's measurements and listening reports that the synergy version of this combination plus 1 or 2 8" woofers crossed at 650 Hz or thereabouts give good point-source performance, smooth FR and controlled directivity.

Im interested in finding out if a similar combination in a more typical 2-way or WHW configuration might give similar performance, if a large enough woofer (10", 12", 15" or 18" is used to match the horn's dispersion pattern at the crossover.

My listening room is 13' wide, 24' deep and 9' tall. I'm usually sitting about 12' from the speakers which are toed-in near the corners of one end of the room. I currently have 2 B&W 640i as the mains, which are probably bouncing sound off the walls, roof and floor like crazy. (though I use the receiver's Audyssey Curve Editor to get a flat FR at the listening position - confirmed by REW).

I wonder if I a new (traditional) horn build can control directivity enough with the horn and tweeter, to avoid fussing with the synergy taps for the woofers, and still get close enough to the 500 hz directivity control... Thoughts?

Thanks - Six - Minneapolis.
 
There are few projects that are similar in concept to what you are proposing.

There is the Raptor by Paul W which is two 10" Excel drivers MTM with the XT1464.

The Raptor ... a 10" MTM

A couple of Scanspeak 10" drivers or those from Dayton or the 10" version of SB driver would likely work pretty well without the high price of the Excel's.

Or this one which uses a BMS Coaxial Compression driver to get low and cross to two 15" drivers in MTM.

Faital 15PR400, BMS 4594 MTM - Speaker Design - Data-Bass Forums

If you want to avoid fussing using a 1.4" compression driver would bolt straight on and something like the Faital HF146 could use a low crossover point if the SPL expectations are reasonable.

To get directivity at 500Hz would need a much bigger horn and to get something as smooth as the XT1464 is quite a difficult construction project.

Bushmeister's design works well because the drivers chosen work well together and injecting the woofers in the horn improves the directivity.
 
You are in luck, I found the files!

Here are the STL files for my version of the Xbush speaker. LTH horn wall adapter for woofer mounting, 6-hole drill template for horn wall, DC200 cone volume fillers, and 3 sizes of SB65 throat adapters.

Enjoy!

XRK971 - Thank you for sharing these files, and I hope this is not asking too much, if it is - I apologize in advance, and will not mind if my questions are ignored...

I would like to use one of the throat adapters to mate the SB65WBAC25-4 with the 18 Sound XT1464 (instead of routing a radius at the mouth of the horn to fit the larger cone driver)

Here are my questions:

Would you recommend one version over another? The 3 versions appear to have different thicknesses (Which would impact the transition angle between driver and horn) and different recesses for what I'm assuming is driver surround at X-Max. Is there a rule of thumb to follow when choosing a throat adapter? (Gentle transition vs shortest path?)

I don't have a 3d printer so I was planning to use a service to have the adapters printed... What might be some recommendations for filament type and printing resolution to specify?

Thank you again, Six - Minneapolis.