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Couple of questions on a DIY kit

 
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bepaald
Introductory Contributor


Joined: 25 Aug 2013
Posts: 5

PostPosted: Fri Aug 08, 2014 9:17 am    Post subject: Couple of questions on a DIY kit Reply with quote

I have in my possession an old DIY kit from KEF. It contains:

- 2 x T27 tweeters (SP1032)
- 2 x B110 (SP1057)
- 2 x B200 (SP1039), one of which unfortunately has some serious coil rub.
- 2 x SP1004 crossover

So, I basically have these to spare. I used one of the B200s to fix my 104aBs (hence the coil rub in the one of the ones I have left), and have neither the skill nor the need to build a speaker set out of these parts. I do have a couple of questions maybe you could help me with.

First of all, who can tell me anything about the crossover. I don't know anything about it. How would a speaker built with these parts compare to my 104aBs?
Second, in preparation of a possible sale, I was measuring the resistance of the drivers. All the B110 and B200s measure the listed 8 Ohms pretty much exactly. The two T27's both measure 7 Ohms. Is this normal or indicative of a problem? Does it show its age or have they probably always been like that?
Lastly, does anyone have any clue what something like this is worth? As a set or as separate parts? I don't need or expect to get rich on this by the way, they are really just in the way at this point.

Thanks!
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speakerguru
Über Contributor 1000+


Joined: 18 Nov 2005
Posts: 1192
Location: Green Hut, Tovil

PostPosted: Fri Aug 08, 2014 9:30 am    Post subject: Reply with quote

SP1004 is a Concerto XO intended for use with T27, B110 and B139 units. You don't have any B139s, so the set is incomplete.

The d.c. resistance of nominal 8 Ohm impedance KEF units of that era was around 6.6 - 7.2 Ohms, so there is nothing wrong with them, although I'm surprised that any of your units measure as high as 8 Ohms. How accurate is your meter? Did you include leads?
Impedance is often measured in the flat part of the curve, just above resonance, around 100-150Hz.
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willem-57
Senior Contributor 200+


Joined: 18 Jul 2014
Posts: 218
Location: Netherlands

PostPosted: Sat Aug 09, 2014 7:44 pm    Post subject: Reply with quote

So, try to buy a set B139B's, maybe someone can tell him witch B139 it should be, spnr ?
http://www.kef.com/uploads/files/en/kef_units/A%20History%20of%20Kef%20Drive%20Units%20issue%203.pdf

If it is complete i think you gonna sell it easily.
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