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Old 23rd September 2001, 12:43 AM   #21
Geoff is offline Geoff  United Kingdom
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Simon

Falcon Acoustics ( http://www.falcon-acoustics.co.uk/ ) are listing the Uni-Q (Q200H) at 76/pair (Sept. 2001 price list - a bargain if they still have some in stock).

If you are thinking about the LS3/5A, please bear in mind that this speaker was designed on the original B110. Later B110s had different T-S parameters and may need some changes to the cabinet/crossover. I have copies of both B110 datasheets if you need them (and the LS3/5A crossover schematic) and the original design specification can be obtained from the BBC site.

Also remember that this design is very inefficient though it gives a good sound. In case it is of interest, a few years ago I made a direct comparison between my LS3/5As and the Q60s. The LS3/5As were smooth and enjoyable but the Q60s had more clarity and detail and seemed to be more 'integrated'. The conclusion of the comparison was that I use the Q60s and the LS3/5As are stored in a cupboard.

Geoff
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Old 23rd September 2001, 02:27 AM   #22
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Simon,
Yes, I think I remember seeing something to the effect that Rogers had made a "Limited Edition" or some such, but the cost was horrendous. ($3000? Surely that can't be right?) The only difference I saw was that the front of the cabinet was veneered and lacquered about 18 coats deep, vs. mine which have a thin coating of what is probably urethane.
Geoff,
If you're speaking of the SP1003 and SP1057 versions of the B-110, they were actually made at the same time. KEF used the 1057 in-house, and sold the 1003 to the masses. The B-110s I have are actually the SP1057 versions, and yes, they're slightly different from the 1003 (which is, I believe, the version that was used in the LS3/5A). If there were other SP versions, I'd be interested in knowing about them.
While I haven't heard the coaxial KEF drivers they're making now--and so have no opinion--I agree that the LS3/5As are somewhat less than state of the art by today's standards (mainly, I think, the T-27 at fault). And we're also agreed that they're inefficient. Somewhat soft on top, slight bump before the rolloff on the bottom, but as you said, a pleasant sounding speaker. Their imaging capabilities, however, are still better than many of the highly touted speakers currently on the market. I use mine on my video setup, along with a few B-139s for the deeper bass. I'm using a compensation network not unlike the Linkwitz one to increase the drive down to about 18Hz, then rolling off. Not optimal, as the B-139s would be happier from 40 or 50Hz up, but it does okay, considering that I consider the video rig very much to be second rank to my main audio setup.
I'd be happier if KEF were still making drivers that we could buy. I miss them.

Grey
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Old 23rd September 2001, 09:57 AM   #23
Geoff is offline Geoff  United Kingdom
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Grey

The original LS3/5A used a specially selected B110A SP1003. Two versions of the B110 were available to the home constructor here in the UK, the B110A SP1003 and the B110B SP1057.

I have two differing datasheets for each of these drivers. Unfortunately KEF did not date the datasheets but, from memory, one set of data was from the early '70s and the other from the late 70's / early 80's. The T-S parameters vary siginicantly for the same SP number. There is a similar variance for the B139B SP1044.

I can scan and send you datasheets for any of the KEF DIY drive units (B139B, B200A, B220G, B110A, B110B, T27A, T33A, T33B, T52B) if you are interested. I also have copies of all the original KEF DIY construction designs going back to the original Concerto/Chorale/Coda equivalents.

I too regret the loss of the KEF drive units. I have used nothing else for the past 30 years, in a wide variety of enclosure designs (TL, ABR, sealed, ported), all of which have given a great deal of enjoyment.

Geoff
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Old 23rd September 2001, 11:28 AM   #24
Simon is offline Simon  England
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Geoff,

Okay I checked out Falcon Acoustics - this looks interesting. Do you know where I can get hold of spec sheets for the Q200H, BD200H & B200H or the construction notes for kits 60, 80 & 90.

Cheers,
Simon.
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Old 23rd September 2001, 11:34 AM   #25
Geoff is offline Geoff  United Kingdom
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Simon

E-mail me so that I know where to send it and I will scan my copy of the KEFkit datasheet.

Geoff
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Old 23rd September 2001, 11:45 AM   #26
Simon is offline Simon  England
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Grey,

Rogers "special edition" seems to be aimed fairly & squarely at the Japanese market. Those guys are nuts for British HiFi (and they love anything tiny) - and will pay thru the nose for it. I'm willing to bet Rogers haven't made that many European sales. Again a shame really. A great British product (originally 'inexpensive') now out of reach for most of us who live here.

On the 'hifi-ness' of LS3/5 compared with more modern stuff I agree with you & Geoff. They're not perfect but there's just something about them - very listenable. I would love to hear one with something decent up top, like a SS D2905/9500 or similar.

Simon
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Old 23rd September 2001, 04:49 PM   #27
tvi is offline tvi  Australia
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Their is another source of dual concentric drivers, unfortunatly its a car audio maufacturer.

Clarions current range off drives includes the <a href="http://www.clarion.com/Products/Speakers/DCD_Design/SRX1683/srx1683.html">SRX</a> series, these are dual concentric drivers, the tweeter clips in and out of the centre of the cone, not mounted above the come like most car speakers.

Being car audio there are no frequeny response graphs much less waterfall plots available, but their is a chance they could sound alright.

Regards
James
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Old 23rd September 2001, 04:54 PM   #28
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Geoff,
At least as of the late '70s and into early '80s the B110 SP1003 and SP1057 were both available in the US market. I have unearthed a KEF price sheet of the Dealer Confidential sort dated February 1, 1980 that lists both simultaneously. If I recall correctly, they had both been available for a while before that, but for how long I can't say.
Incidentally, this price list shows no fewer than four versions of the B200 available at the same time: SP1014, SP1039, SP1054, and SP1063. There is only one B139, although there is a passive radiator version of the driver that I had forgotten about. The two B110s. One each, T27, T33, and T52. And two versions of something called a P200 (SP1070 and SP1069) which I don't remember at all.
That's not to say that the SP1057 was available as a DIY unit. I had to prevail on a friend of mine to get me the drivers, as KEF was very jealous about "their" versions of these drivers. I had some reason that I got the SP1057 vs. the SP1003, but I've long since forgotten what it was. Clearly, I wasn't going to make an exact clone of the LS3/5A. These days I'd probably forego the passive crossover entirely and biamp the things.
Unless...do you have a set of diagrams/schematics for a speaker using the T27 SP1032/B110 SP1057/B139 SP1044? I know the Cantata used the B110/B139, but used a different tweeter. The DN12 SP1004 crossover network was designed for the T27/B110/B139 combination, but the B110 they had in mind was the SP1003. The spec sheets I have for the B110 SP1003 & SP1057 show identical electrical characteristics (except that the SP1057 can take more heat), but differ in the T-S parameters. The SP1057 was also slightly more efficient. I have only one spec sheet per SP number; they date from that same general time period, but like yours, there's no explicit date on the sheets.

Grey
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Old 23rd September 2001, 05:33 PM   #29
Geoff is offline Geoff  United Kingdom
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Grey

We're deviating somewhat from the original topic of this thread so I hope Simon will forgive us.

The only official KEF DIY designs (so far as I am aware, and I think I have all the relevant leaflets) that use the B139/B110 are the Concerto equivalent (B139 SP1044/B110A SP1003/T27A SP1032/DN12 SP1004)and the Cantata equivalent (B139 SP1044/B110B SP1057/T33A SP1074). I have cabinet designs and crossover schematics for both of these.

The were of course a number of other DIY designs published that used the B139/B110/T27. Falcon Acoustics (link in previous posting) still supply crossovers for these designs and a look at their list will indicate the source article. The best design I have seen for these drivers is the one that Linkwitz published in Wireless World and later in Audio Amateur. This uses active filters and electronic time/phase alignment. A copy of the original artices can be downloaded from his site (I posted the link previously in this thread).

In view of the number of times I have supplied parts of the information in the past, I will tabulate the T-S parameters for all the drivers and will email a copy to you. If you want the amplitude response and impedance graphs then I will scan the appropriate datasheet.

Geoff
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Old 23rd September 2001, 07:46 PM   #30
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Geoff,
Unfortunately, having only the B110 SP1057, the Concerto (SP1003) crossover won't work. The problem runs the reverse direction with the Cantata--I've got the SP1057, but the tweeters I have (T27s) are different.
I'm familiar with the Linkwitz article. In fact the copy I have is a KEF reprint. If/when I get the time to follow through with the project, I'll probably just do an active crossover, whether in the Linkwitz vein or something else--possibly a discrete implementation of his crossover. He certainly wasn't shy about the use of opamps.
Perhaps I should have gotten the SP1003 version of the B110 after all. As I said, I'm not clear at this point as to what attracted me to the SP1057, but I'll cobble something together when I have time. I was hoping that an appropriate passive crossover design was available so that I wouldn't have to throw together that many more amps. At present I've probably got more channels of amplification on hand than anyone else in town, but am not anxious to lengthen my lead. I'd be more than happy to let someone else take over.
Thanks anyway.

Grey
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