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In the Forum: Horn-Loaded Speakers
In the Thread: My Multi-way Horns

Post Subject: My Multi-way HornsPosted by skushino on: 11/29/2009

My current speakers are Edgarhorns with the straight 80hz upper-bass shell. The bass never sounded correct to me. The problems with Edgar's mid-bass are well documented at this site and elsewhere. I tried some simple modifications to the crossovers and amplification and obtained improvements in the right direction, but at this point I want to take a different path with a new multi-way system. My plan is to implement the new system in 3 phases, so that I can monitor the effects of each change on its own. Here is the plan:

	Bandwidth	Driver	Horn	Remarks

Phase 3	> 10k	Fostex T900A	Bullet tweeter	Replace Edgar sub with stereo tapped horn subs
	> 1200	JBL 2441	Edgar 350Hz tractrix horn
	240 - 1200	Faital M5N12-80 5"	142 Hz 4" throat tractrix horn
	75 - 240	12" 'x'-driver	70hz 8" throat
	< 70	Dual B&C 8PE21 8" woofers	Stereo tapped horns


Phase 2	> 10k	Fostex T900A	Bullet tweeter	Add 70 Hz midbass horn -> 5 way system
	> 1200	JBL 2441	Edgar 350Hz tractrix horn	raise upperbass high pass xover from 135 -> 220
	240 - 1200	Faital M5N12-80 5"	142 Hz 4" throat tractrix horn	lower sub xover from 120 -> 60
	65 - 220	12" 'x'-driver	70hz 8" throat
	< 60	JBL 2240 18"	Edgar Seismic Sub


Phase 1	> 10k	Fostex T900A	Bullet tweeter	Replace Edgar 80Hz horn with 142Hz upper bass horn
	> 1000	JBL 2441	Edgar 350Hz tractrix horn	raise MF xover from 500 -> 1000
	135 - 1000	Faital M5N12-80 5"	142 Hz tractrix horn 4" throat	raise LF xover from 65 -> 120
	< 120	JBL 2240 18"	Edgar Seismic Sub


Edgarhorn	> 10k	Fostex T900A	Bullet tweeter	Base line
(current)	> 500	JBL 2441	Edgar 350Hz tractrix horn
	80 - 500	Electro Voice EVM-15L	Edgar 80Hz 10" throat horn
	< 80	JBL 2240	Edgar Seismic Sub

The system will grow from its current 4-way configuration to 5-ways. I'm ok with the current mid-range and HF. Attention is focused on the region below 200hz.

Phase 1 replaces the Edgar 80hz horn with a Hasquin 142hz round tractrix with a 4" throat driven by a 5" Faital Pro M5N12-80. I also have a couple of 8" drivers to try in this horn, Fane Studio 8M and B&C 8PE21. The final selection will be based on results of listening to all. Naturally the crossover points will need to be adjusted for the new horn. I plan to get an RTA to help integrate the new horn. In the beginning this horn will turn on around 135hz, but in the final configuration it will be used an octave higher, turning on around 240hz.

Phase 2 adds a mid-bass horn. This is the most important and challenging part of the project. If I make a mistake here, the project would be a total failure. This horn should cover around 70 - 240hz. At this point I'm looking at a rectangular 65 - 70hz hyperbolic-expo profile with 8" throat driven by a 12" 'driver x'. I don't want to reveal the driver yet as there is some controversy around the application and further modeling needs to be done. This driver has never been used in a similar application that I'm aware of. There may be a good reason for this, but I'm stubborn and need to try it for myself. The driver selection is based on one criteria - luscious and colorful tone. Initial results from hornresp show good potential in a front-loaded horn application. In case my x-driver proves unsuitable, I will go with a more conventional 12" woofer.

Phase 3 replaces the Edgar Seismic Sub with stereo tapped horns. These will be dual P-P configuration. John Hasquin has been very helpful on this part.

For amplification I have ML-2s.

The stand is a major project all by itself. My current plan is support the 142hz horn on a block like Romy's. Then need to fabricate a stand for the mid horn above, with the Fostex tweeter in between the 142 horn and mid horn. I am planning to hang the mid-bass horn from the ceiling vertically aligned with the other horns. Partly because there is no other place to put them, to obtain coupling with the ceiling, and also to be more off-axis in the hopes of mitigating excess hf coming out of this horn being heard at the listening seat. It might look something like this:

Disregard the different color schemes, I was trying to get a visual of different ideas. Kind of leaning towards the 'Japan horn" color scheme on the left.

I expect this project will evolve over the next several months, and then take several more months before getting decent results. The first part is getting John's 200 pound horns shipped to Seattle, paint them, have stands built for the mid and HF, then finally working on implementing them. I don't even want to think of the nightmare of phase 2 yet - fabricating mid-bass horns and then hanging them from the ceiling...

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