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A six year ago or so when I played with different compression drivers I bought a pair of Dukane 5A540 and at that time I was not able to find any information about them. Nowadays I was pointed out that an eBay sealer “ bayleafs” actions a pair of Dukanes and provided a very good description about them. Since the item description will be gone with time and the description I found is valuable (regardless agree I with it or not) I decided to re-post the bayleafs’ text at my site. I think it well worth it and it goen SOME intonation about the Dukane 5A540 drivers. 

So, here and down the bayleafs’ text:

Rather than designing and building their own sound drivers and horns, Dukane licensed production from recognized pro audio manufacurers. These 5A540 compression drivers, which are an excellent match for the Dukane/Vitavox 5A325 horns, are generally recognized as rebranded JBL's.

The Dukane 5A540's get excellent reviews. I've come across many favourable comparisons to the JBL 175/2410 drivers and the related Coral M-100. While most people have focused their attention on the JBL 2440/2441 these ones have gone relatively unnoticed.

I've also previously owned a pair of JBL 2441's. They're very nice compression drivers, but frankly the 5A540's beat them hands-down except in power handling. There's a sweetness and brilliance about the 5A540's that the 2441's just can't match on their own. Add in some EV ST350A tweeters, however, and it will be a different story -- but then it's also a 3-way system.

If you're looking for a 2-way system, the 5A540/175/2410 is an excellent choice for a mid-high driver. If you currently have SET amps, or are planning on getting them, the 5A540's are a perfect match for the efficiency requirements of SETs.

Physically the 5A540/175/2410 series of drivers have an additional advantage over the JBL 2440/2441. The throats in the 2440/2441's are plastic and can crack pretty easily allowing the magnet to go out of alignment. Although the magnetic gap is protected from a misaligned magnet most people do not value a driver with a cracked throat.

The 5A540/175/2410's have aluminum throats which have the strength to resist magnet shifting and will become a much better investment over the years. I fully expect this range of drivers to continue to increase in value and eventually surpass the value of the 2440/2441's. Original diaphragms already cost over $250 each.

Dukane didn't publish any specs on these drivers, at least from what I can find. Most people go to the JBL 2410 specs for information.

As you can tell the specs are pretty close. The Coral M-100 appears to have the flatter response over the JBL 2410. The flux density and weight are also greater. JBL claims a sensitivity of 117 dB over the Coral's 105 dB but that's into a plane wave tube, not a horn. Depending on the horn design you can expect about 18 dB greater output from a plane wave tube than a horn.

My curiosity got the better of me after I found these Coral M-100 specs on the web.

When I weighed the two Dukane 5A540 drivers to get an idea of shipping cost they were just under 19 lbs, where they should've come in at 16.3 lbs (if they were based on the JBL 2410). So I got out the ruler and measured these. They do measure larger than the JBL 2410's, which are 114mm x 98mm. The Dukanes measure 116mm x 103mm (104mm with the gasket). The Dukane 5A540's are definitely larger and heavier than the JBL 2410's and match almost exactly the Coral M-100's in weight and size.

So they're looking suspiciously like they have Coral M-100 specs, especially with the JAPAN label on the gasket. I wouldn't say the Dukane 5A540's have the Coral diaphragms because I can't say what the Coral diaphragms look like. I do know they'll take the same diapragm as the JBL 2410. They do however appear to have the Coral NKS-5DG Alnico magnet going by the weight and the driver size. If so, these are rare birds indeed. Google NKS-5DG and find out!

To that fella who suggested to me these Dukanes may have been made by Coral, it looks like you were likely right. But as I said in my email I can't make that claim, and I don't. What I can say is the Dukane 5A540 is heavier and larger than the JBL 2410. It is very efficient (which could be due to the higher gauss NKS-5DG Alnico magnet) and has a wonderfully sweet sound.

I've been experimenting with wide dispersion sound sources in smaller listening spaces. I used to think that 120 horizontal degrees of dispersion was overkill for a living room, but since installing 2 EV Sentry IV cabinets, and experimenting with the 5A325/5A540 Dukanes and the Altec 1505B/288, I've found a definite improvement in sound from wide dispersion speakers.

In comparison to professional studio monitors, the perception of depth and spaciousness opens up over most of the listening area. It's as if there are quadratic diffusors (panels which receive and reflect sound in all directions) on the walls. Even a friend who runs a recording studio was impressed.

The studio monitors had a definite zone where they sounded best. The room seemed to have well-defined points where the sound coverage wasn't quite right. With the wide dispersion horns sound coverage was virtually complete with a smooth, natural sound in all listening spots.

The EV Sentry IV's have a horizontal dispersion of 120 degrees and the Dukane 5A325's have about 100 degrees. In comparison the Altec 1003 has 90 degrees and the Altec 1505, 105 degrees.

It's still too early for me to say for sure, but I suspect the large horizontal dispersion horns sound much better mainly because they fill the listening room with sound much like quadratic diffusors do.

Think of it this way. A normal speaker system spreads out phase-coherent sound like a laser beam spreads out light coming through wide angle optics. The room will be filled with light (over the area the optics cover) but the light will still be mostly phase-coherent, meaning in-phase. Our eyes really have a problem with focusing on objects illuminated with this type of light source.

If you take this same light and diffuse it, the light no longer has phase-coherence. Photons arrive out of synch with each other and our eyes can focus clearly. With sound I believe our ears work the same way -- we have the ability to sound-focus with diffused sound sources.

It seems to me that multicellular and sectoral horns create better sound diffusion (phase incoherence) as well as better sound dispersion (sound width). Line arrays should also work the same way.

Once you get into larger listening spaces sound diffusors and absorption panels are absolutely necessary. Standard pro sound design practice is to keep the sound off walls and ceilings to reduce reverberant energy. Small rooms have a proportionately larger amount of sound absorption and benefit from larger amounts of room reverberation... if the reverberant energy is diffused throughout the room.

Why do I bother saying all this? I love the sound. Find someone who has a properly set up horn system and give it a good listen. I really think you'll like it.

My future sound system is slowly taking shape. I'm using the dimensions of the Dukane 5A325 to make myself two bentwood multicellular horns with phenolic drivers. These will be crossed over near 5-7 kHz to a wooden tweeter based on the EV ST350A (baby cheeks horn) for the high end. The low end crossover will be in the range of 300 Hz to an asymetrical folded horn cabinet. The amp will either be a matrix tube amp, or a SET, or both at various times.

In case you're wondering why I would ever part with these very nice little drivers... I've fallen in love with the sound of phenolic compression drivers and it makes more sense for me to move up to the 2" drivers so they can safely get down to the lower frequencies.

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