Should I refurbish a set of jr149 speakers

[jjl]

I have a set of jr149 speakers that are showing their age a bit. I purchased them new back in the 70's.
I am wondering if it would be worthwhile rebuilding them with some more modern components and if so what would you suggest. The woofers are the Kef B100 and I am not sure what the tweeters are. I do not want to alter the cabinets at all so I can retain the originality by simply replacing the old parts if needed (probably not, but not a bad idea).
Any suggestions would be appreciated.
Thanks
Jeremy

[dabbler]

You do realise your speakers something of a collectors item? They are worth a small fortune over here. Rebuilding them with "modern components"is a bad idea. Really.

[Charles Darwin]

Indeed they are collectors items by now.
I'd sell them and build something better with the profits.

[sreten]

Hi,

The drivers are the high impedance KEF B110 and T27 used in the original
high impedance BBC LS3/5A and as such are highly desirable as spare parts.

You may be able to sell the drivers (and c/o) as parts for more than the
speakers. If so the cabinets would make a nice basis for a project.

rgds, sreten.

[system7]

Only chipping in because Jim Rogers was a bit of a legend. He based the JR149 on the famous tiny BBC LS3/5A which he also designed IIRC. Better cylindrical metal cabinet and a bit more bass extension.

Lots of info available like this site: jr149

Looks like the original design was very crossover equalised for the KEF B110 SP1003 bass and T27 treble. Baffle step, some reduction of peaks and Zobels an all. Later designs used a Focal 110mm unit and scanspeak tweeter with simplified 3rd order filters. Nothing there that ought to deteriorate too badly except the usual glue and surrounds and covering foam, I'd reckon.

[planet10]

Originally Posted by sreten

The drivers are the high impedance KEF B110 and T27 used in the original
high impedance BBC LS3/5A and as such are highly desirable as spare parts.

The 15 ohm LS3/5A used hand picked, but standard 8 ohm parts i believe.

dave

[sreten]

Originally Posted by planet10

The 15 ohm LS3/5A used hand picked, but standard 8 ohm parts i believe.

dave

Hi,

Different version of the B110 I believe to the later version, T27 the same.

Before 1987 the 15 ohm version LS3/5A used a KEF B110 SP1003.
Post 1987 the 11 ohm version used the KEF B110 SP1228.

There are four versions of the B110, all "standard" 8 ohm.

The 11 ohm version requires matching drivers and c/o, as driver
variation to some extent was compensated in each crossover.

PITA having to check something true because being contradicted. Pre
1987 T27's are still worth more even though they are nominally the same.

Whatever the details (and there are lots more to argue about) the
drivers are worth a lot in the far east, if correct type and vintage.

rgds, sreten.

[planet10]

B110 SP1003 is an 8 ohm driver -- essentially what i stated.

http://homepage.mac.com/planet10/TLS...110_SP1003.gif

the high impedance KEF B110 and T27

There are four versions of the B110, all "standard" 8 ohm.

Yes, there are no high impedance B110 (or T27)

dave

[sreten]

Hi,

Post #4 didn't come out right. The versions are the same as in the high
impedance version of the LS3/5A, not high impedance driver versions.
(Though some LS3/5A'ers might refer to them that way).

rgds, sreten.

[jjl]

Thanks to all for your information. I will have to now consider what to do with these speakers if they are worth preserving, or selling the parts. I will take a closer look at them and find out exactly which model or year they are. The foam covers have gone completely, just rotted away and turned to dust but the rosewood cabinets are in excellent condition.