The latest Bullfrog is coming up.
Its driver is easy to recognize, but there is more to it.
The driver on the left image above is most likely a McCauley.
The Bullfrog was taken out of production for a number of years after the US manufacturer closed its doors.
Its driver is easy to recognize, but there is more to it.
The driver on the left image above is most likely a McCauley.
The Bullfrog was taken out of production for a number of years after the US manufacturer closed its doors.
Did someone mention the woofer? That would be the jewel of the design. That and the horn, but being crossed at 650hz, wtf? The majority of the woofer is covered by the horn, that would have to be the major drawback of the design though I'm not sure how that fairs out. I guess since its symmetrical from every angle, eq takes care of that problem. Also, the horn is too small to load properly to 650hz but I guess its more of a waveguide so whats the totality of that? Lowered sound quality I suppose. I'm not knocking the design, I love it actually, but I am trying to nit pick....makes me feel better since I am already invested into my/our design. At the very least, my bottom line was 30ish to 20khz-ish, linear, fewest amount of drivers possible. I think at the beginning of the thread I was talking of FAST (aka WAW?) configurations. The bullfrog isn't going to play linear into the 30's but it would make a nice combo with subwoofer, for sure. Just for fun, is there a nice woofer and horn available for the DIYer to create their own Bullfrog? I didn't even know you could buy horns that fit into the available coaxial woofers.
I like it! I was interested in the Beyma co-axials briefly...like has been said, there is no silver bullet....yet.... I would like to find some affordable wooden horns though. Otherwise I am happy with the path that I am on. I've come to understand that fiberglass horns have their own set of drawbacks and why wood is the sought after horn.
There are plenty of 15" coaxials with horns available from B&C, Beyma, BMS, Oberton, RCF etc.
The RCF CX15N351 is quite special, because of the bigger compression driver.
The horn is rather small indeed. In order to enlarge the mouth somewhat, Martion mounts the inner convex Aluminium ring.
The RCF CX15N351 is quite special, because of the bigger compression driver.
The horn is rather small indeed. In order to enlarge the mouth somewhat, Martion mounts the inner convex Aluminium ring.
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But! The RCF in the Bullfrog is made to Martions specs. And while there's no complete list, because these are trade secrets, I can tell the mods are subtantial.
I'll post more info later. l'm on the phone now.
I'll post more info later. l'm on the phone now.
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The RCF is a nice coax, but I would prefer a soft suspension in the comp.
The driver is basically the N640.
According to the info I've gathered Martion uses another diaphragm, but the big break-up spike is still visible in measurements of the latest Bullfrog.
The driver is basically the N640.
According to the info I've gathered Martion uses another diaphragm, but the big break-up spike is still visible in measurements of the latest Bullfrog.
The good thing about the RCF CX15N351 is presumably a better handover between woofer and comp.
The passive Bullfrog, which was reintroduced some time after the active, has a 1" comp. and XO at 1500Hz.
The driver is, again, not identical to the RCF 15CXN251.
The passive Bullfrog, which was reintroduced some time after the active, has a 1" comp. and XO at 1500Hz.
The driver is, again, not identical to the RCF 15CXN251.
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They both have the same problem in that its Fs needs to be either well above or well below its pass band and why the pioneers opted for thin tin horns encased in tar.
For the DIYer; MDF, better still, cheap particleboard with concrete, stone, etc., obviously best, then properly seal the inside since there's no such thing as too smooth, especially in the first 4-5" [includes any driver internal throat], just a point of diminishing returns.
Anybody tried any of the new super slick spray coatings used on race cars, etc., on horns?
GM
Another difference: the exit of the comp. driver in the Bullfrog Active is 1.5", instead of 1.4" as with the regular CX15N351.
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Yes, a damping/mass loading box is one way, but I've been exposed to a number of DIY wood horns that had too high an Fs, though none you listed except some metal Vitavox that did, so obviously can't comment on them specifically.
GM
GM
Speaking of black, apparently a German got fed up with his historic horn system:
Western Electric Horn 16a, 2x 555a, 2x 594a, 2x Amplifier WE46c.
The first time ever I see original WE gear for sale in Europe.
Asking price is €140.000.
Western Electric Horn 16a, 2x 555a, 2x 594a, 2x Amplifier WE46c.
The first time ever I see original WE gear for sale in Europe.
Asking price is €140.000.
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The left horn below needs damping, the horns on the right not necessarily, which would also be rather ridiculous at £4500 each.
Years ago, I saw a pair of original (metal) CN157 horns for sale, including drivers (not the S2 shown).
The seller didn't know what he was dumping and I was primarily fascinated by the faded Vitavox logos that were barely visible in the horn mouths, so I agreed on €25.
Then someone else saw the ad and outbade me, before I could pick 'em up.
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Wooden horns made by Martion, the non-wood version and another peek inside the older Bullfrog cabinet.
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Interesting stuff! It looks like the cabinets might have a pre-tensioning device.
On the same German ebay site on which the WE stuff is offered, several G.I.P. and Line Magnetic items are for sale... but not a single Martion product (which is German).
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