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KEF 104abs - Is this a true upgrade?

 
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mikeytheo
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Joined: 16 Apr 2007
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Location: Sydney Australia

PostPosted: Fri Sep 21, 2007 1:41 pm    Post subject: KEF 104abs - Is this a true upgrade? Reply with quote

Hi,
In my frequent perusing of ebay, I have noticed this pair of 104ab's that have been relisted many times - mainly due to the $1300 (aus) starting price. My question however is in the description which includes....

...nice pair of Kef 104ab Speakers that are upgraded to true 3-way (installation of Genuine Kef woofer instead of the original passive radiators).

Now, as a 104ab owner, I am interested to know if this is indeed a genuine upgrade - excuse my technical idiocy, but ain't the original a 'genuine Kef woofer' ?

This is the item number is anyone is interested...
150162775187 (just type it into the search box from any ebay site worldwide)
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ColinR
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PostPosted: Fri Sep 21, 2007 2:22 pm    Post subject: Reply with quote

Ask the guy for a copy of the crossover schematic and share it around so we can all have a laugh Very Happy .

Unless the cabinets have a "Tardis" quality to accommodate some internal modifications to make these speakers a type of "active line" - speakers with different resonant frequency at each termination of a short transmission line - RUN Rolling Eyes .
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proffski
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PostPosted: Fri Sep 21, 2007 5:50 pm    Post subject: Reply with quote

Oh Dear Me Indeed! A picture of the internals would be nice too!
I love EPray...

Just sent an email to Horatio regarding the item.
I've requested some guide to the loading technique used for the "Proper" LF driver as well as the crossover arrangements for the drive units also some more pictures...
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proffski
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PostPosted: Tue Sep 25, 2007 10:04 am    Post subject: Reply with quote

BEHOLD!

At last an answer regarding the KEF "Improved 104aB"!

Here it is, brace yourselves: Ready?

Tks for your interest. The conversion was done by an expert and I don't know anything about electronics and don't have the copy of the crossover setup.
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centaurus
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PostPosted: Tue Sep 25, 2007 7:09 pm    Post subject: Reply with quote

umm, i don't think there's enough internal volume in the cabinet for BOTH the B200 AND an active B139. right?

Rbby
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proffski
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PostPosted: Tue Sep 25, 2007 7:27 pm    Post subject: Reply with quote

Yup! Colin has given the answer somewhat tongue in cheek but with more than a grain of fact.

Unless the 'expert' was also a magician the B200 should then ideally be in its own enclosure. You could arguably add equalisation for the "proper" drive unit to compensate the less than ideal theoretical volume, so then it gets ever so complicated and messy.

Nah, the guy is a typical ePrey truth stretching enhancer…
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mikeytheo
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PostPosted: Mon Nov 05, 2007 3:08 pm    Post subject: Reply with quote

He dropped the price to $1200 when listed for the upmteenth time - still no takers. Surprise!
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proffski
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PostPosted: Mon Nov 05, 2007 7:24 pm    Post subject: Reply with quote

mikeytheo wrote:
He dropped the price to $1200 when listed for the upmteenth time - still no takers. Surprise!


Aw... There must be an idiot out there somwhere!
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Davethreshold
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PostPosted: Fri Dec 21, 2007 7:28 am    Post subject: Reply with quote

proffski wrote:
mikeytheo wrote:
He dropped the price to $1200 when listed for the upmteenth time - still no takers. Surprise!


Aw... There must be an idiot out there somwhere!
I bought 'em! Just kidding. Laughing I just made a post about my friends 104B's. Maybe they are the AB because they look exactly like that. Anyway......does anybody think the Ebay guy will blow up his midrange driver from the pressure of the B139? Here's another idea: He could run them passive, and do what Faber did, which was to put different caps across the terminals of the B139. Idea That will vary the mass of the driver, and gives different tuning frequency's. (I think it was the Faber Extrema)
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proffski
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PostPosted: Fri Dec 21, 2007 8:16 am    Post subject: Reply with quote

The Faber did in fact use switched resistors across the B139, clever, very clever...
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Davethreshold
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PostPosted: Fri Dec 21, 2007 8:54 am    Post subject: Reply with quote

proffski wrote:
The Faber did in fact use switched resistors across the B139, clever, very clever...
Oh o.k. I was thinking caps. It was really clever. Those Extrema boxes. LOL They took about 1-1/2 inches of solid walnut, heated and steamed it, then compressed it to about an inch or so. - Incredible. I heard the more recent, and cheaper ones he made - 2 way, scan speak drivers, and floor standing. They went for about $2,500 U.S.D. and wow. That guy knows what he's doing. I can't find them on his site now though. they were at Tweeter in the U.S. here, but they don't have them any more.
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mikeytheo
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PostPosted: Thu Mar 27, 2008 1:31 pm    Post subject: Reply with quote

For interest sake - somebody finally bought these for $500.
Has been trying to flog the Target stands now for $500 for the past three or so months.
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proffski
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PostPosted: Thu Mar 27, 2008 4:52 pm    Post subject: Reply with quote

mikeytheo wrote:
For interest sake - somebody finally bought these for $500.
Has been trying to flog the Target stands now for $500 for the past three or so months.


One born every minute I guess... Razz
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