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In the Forum: Horn-Loaded Speakers
In the Thread: Another electromagnet driver: Great Vintage Loudspeakers.
Post Subject: Another electromagnet driver: Great Vintage Loudspeakers.Posted by Romy the Cat on: 5/8/2009
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This time from Germany and this time the pattern is very much the similar to the patterns of any other company that sell electromagnet fro Hi-Fi: the semi-idiotic statements-claims meant to impress uninformed peoples and no credible claims about sonic characteristics, or no even implication that the people behind the company has any advanced demands in Sound. The company is Great Vintage Loudspeakers

http://greatvintageloudspeakers.com/

and it looks like they sell direct via Ebay, which is perfectly fine in my books. Still, if a company sells via dealers then it is assumed that all information is possible to get from a dealer. (I know that in reality dealers have no idea how to spell the product name but I said: “assumed”). In case of company deals direct I would like to have on the site more information, I hope the Great Vintage Loudspeakers will do it.

The Art Déco spacers of the company made by a carpenter I pretty much discard and the subject of my interest are only the electromagnet compression drivers or as they call it field-coil drivers

http://www.greatvintageloudspeakers.com/components/

The A594WVL looks like a MF driver. For whatever reason they claim that it is a replica of Western Electric WE594. That is foolish. First of all what is shown in the picture is an indication that it is not replica of WE594. Why they mention the Western Electric, to impress the Morons? That is sad and do not help with evaluation of the seriousness of the peoples who did it.  Also, the Western Electric designs were NOT the optimum designs and it they just “replicated” the WE then they have no idea what they do.

I am not pleased to see phenolic diaphragms in there: the electromagnet with phenolic cone? Come on! That is like a turtle with step-down transmission! The aluminum cone sound interning and their promise of Mylar suspension is VERY interesting. The fact that they have those options is a good sign.

http://www.greatvintageloudspeakers.com/components/a594wvl/a594wvl_ffff.html
The image is correctly to the manufacturer.

I still would like to see the layout of the cone vs. suspension, know the size of the cone, type of phase plug, loading methods and many other parameters to be able to see what they do.

I am glad that they stay with moderate flux density and do not write what other idiots claimed: “our filed coil drivers allow having flux density unreachable by perm magnates.”  Still I am not at ease with the comments like this: “ …  this driver induces 1.59 Tesla in his gigantic magnetic gap…” Where the gigantic magnetic gap comes from in compression drivers? All compression drivers are underhang by nature with no exertion and if the gap is “gigantic” then it is too wide.  The widening of gap is VERY controversial subject in compression drivers and I am not comfortable with it. Are they cooling the coil this way? Do they have problem with overly soft and “loose” suspension? Do they have some benefits with low level signals with extra wide gap?  The electromagnetic flax is not “scrappy” at low levels by nature with permeability look likes dropping faster then with perm magnet. The wide gap would be another “brick in the wall” of worsening the effect, not to mention the heat up the whole driver for unnecessary purpose.

The driver has throat diameter 49 mm, which is 1.929 inches…. Hm… are they kidding? Why not the 50.8mm that would make the standard 2”. That is a mystery to me.

Another comment that they made me do not feel good: “… the magnetic field can be adjusted to your needs respectively to match your woofer and crossover specifications exactly. “ OK, let me say 125 times and for good: the magnetic force of electromagnet driver might NOT be adjusted and particularly in respect to “match woofer and crossover”. Change current across electromagnet changes flux density that impact each and single T/S characteristic of the driver. I am not saying that it would be better of worse but I say he then whole idea of using the specific diaphragm, with specific suspension, with specific loading and with specific damping pattern has any sense ONLY at the very specific flux density. You wish to change the flux density – fine, then redesign the whole driver.  I have seen idiot, who BTW was very celebrated industry reviewer, who wrote that a system with field coil drivers might have a volume control by the mean of flux alternation. I think making public comments like this is a fireable offence but he is the “industry reviewer” – what can you get from him – his title is a diagnose itself… Anyhow, the electromagnet drivers must be sold with very specific very narrow gap of flux density (let say +/_ 0.2T) and the performance of the driver shall be quarantined ONLY at this default flux. I do not want to hear from a manufacture that I even can change flux. If the manufactures even open mouth abbot it then I do not want to hear from the manufacture and the driver they sell is not properly designed.

The Great Vintage Loudspeakers Company has also woofers, duplex drivers (something that I do not like at all). They have a tweeter:

http://www.greatvintageloudspeakers.com/components/a284wvl/

It is field-coil too, but since I do not like the notion of horn tweeters I would move over.

Anyhow, it looks like the Great Vintage Loudspeakers driver are a new player and who knows what they do. The MF driver looks interesting. I never heard them; if anyone did them share your thoughts. The drivers look like 1.8K, it is not clear if it is for a driver or for a pair…


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Rgs, Romy the Cat

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