Hi everyone,
I have been given a pair of speakers that each have a Kef b139 Bass
Kef b110 mid, and Kef T27 tweet. They sound absolutely amazing.
The speakers were hand made, weigh a ton, and are too big and bulky.
Ihave carefully dismantled them and the individual speakers are now boxed.
I was wondering if i could have any opinion on my thoughts. ?
Are they worth me keeping them, with a view to building my own speakers in the future, or have they been far superceeded now by more modern units, ( they are old as you know, but do sound as good as new i reckon )- ........ or shall i try to sell them ??
Thankyou for reading this post
Ade
I have been given a pair of speakers that each have a Kef b139 Bass
Kef b110 mid, and Kef T27 tweet. They sound absolutely amazing.
The speakers were hand made, weigh a ton, and are too big and bulky.
Ihave carefully dismantled them and the individual speakers are now boxed.
I was wondering if i could have any opinion on my thoughts. ?
Are they worth me keeping them, with a view to building my own speakers in the future, or have they been far superceeded now by more modern units, ( they are old as you know, but do sound as good as new i reckon )- ........ or shall i try to sell them ??
Thankyou for reading this post
Ade
I build a pair back around 1979 with these drivers. They weighed approx. 90lbs each!
Did you take a picture of them before dis-assembly?
jeff
Sorry,
I Didnt take any pictures. They cabinets were about 20 inches tall, 15 wide and 15 deep, solid wood, removable grilles, the mid ranges werent ported, but had a plastic tube behind them, there was a switch for the tweeters but that wasnt wired in. they stood on old t.v. stands which were on castors so i could at least move them around. i'd like to rehouse the units but wonder if its worth it ??
I Didnt take any pictures. They cabinets were about 20 inches tall, 15 wide and 15 deep, solid wood, removable grilles, the mid ranges werent ported, but had a plastic tube behind them, there was a switch for the tweeters but that wasnt wired in. they stood on old t.v. stands which were on castors so i could at least move them around. i'd like to rehouse the units but wonder if its worth it ??
Ah, yes, the KEF Concerto. THE 70s classical music lovers favourite! 
Very nice indeed. Whyever did you take them apart?
Falcon acoustics and Wilmslow audio in the UK doubtless offer crossover upgrades, because the non-polar capacitors do degrade with age. But very nice speakers indeed. Probably hard to beat with modern stuff too.
An externally hosted image should be here but it was not working when we last tested it.
Very nice indeed. Whyever did you take them apart?
Falcon acoustics and Wilmslow audio in the UK doubtless offer crossover upgrades, because the non-polar capacitors do degrade with age. But very nice speakers indeed. Probably hard to beat with modern stuff too.
Attachments
Hi all,
just to defend the reason for taking them apart .... They were given to me by someone who had stored them in a shed, and they had got knocked abou a bit, therefore aesthetically not the sort of thing that would be ideal in a room at home that i call my listening room. I could also smell " damp ", and being worried about the main parts, decided to perform the reverse engineering. The units are in good nick and now in the house in a warm environment. also, i like the idea of a cabinet thats more tall and narrow, as my listening room isnt massive. a google search suggests a transmission line design that takes my fancy, Thanks for the pic of the concerto, the units were spaced exactly like that, and if that pleaseing to the eye, i would have left them alone- Ade
just to defend the reason for taking them apart .... They were given to me by someone who had stored them in a shed, and they had got knocked abou a bit, therefore aesthetically not the sort of thing that would be ideal in a room at home that i call my listening room. I could also smell " damp ", and being worried about the main parts, decided to perform the reverse engineering. The units are in good nick and now in the house in a warm environment. also, i like the idea of a cabinet thats more tall and narrow, as my listening room isnt massive. a google search suggests a transmission line design that takes my fancy, Thanks for the pic of the concerto, the units were spaced exactly like that, and if that pleaseing to the eye, i would have left them alone- Ade
My neighbour used to have the Concertos. Very smooth sound.
Someone else I knew had the similar huge IMF transmission lines with a Coles 4001 supertweeter, which were very inefficient and rather TOO smooth IMO.
Your next step is probably to identify the exact SP numbers of the drivers. You could probably build something from a tiny LS3/5A to an IMF type whopper.
Falcon do an LS3/5A kit that just lacks the hard to find drivers. Hours of fun.
Someone else I knew had the similar huge IMF transmission lines with a Coles 4001 supertweeter, which were very inefficient and rather TOO smooth IMO.
Your next step is probably to identify the exact SP numbers of the drivers. You could probably build something from a tiny LS3/5A to an IMF type whopper.
Falcon do an LS3/5A kit that just lacks the hard to find drivers. Hours of fun.
The word i would use instead of too smooth would be consipated.
Your next step is probably to identify the exact SP numbers of the drivers. You could probably build something from a tiny LS3/5A to an IMF type whopper.
Falcon do an LS3/5A kit that just lacks the hard to find drivers. Hours of fun.
My personal opion is that there are much better speakers you can build than LS3/5A -- i recently restored a pair and had the opportunity to compare them to a number of similar size speakers that we have around here.
The XOs are by far the weakest part, not even much of use on them (maybe the chokes). The B110 & T27 are in fairly high demand as replacements for vintage speakers that people want to keep going (just had an inquiry re some T27 for a set of Tanget TM3) so i'd flog them. The B139 doesn't seem to be in as high a demand, it is still a reasonable woofer but does require a big box to get the best out of it. With a pair i would consider building a FAST with them, mating them with a small FR (FF85wk would be at the top of my list). To give you an idea of the size: http://p10hifi.net/TLS/downloads/B139-TTL-map-100707.pdf
Built with a rectangular cross-section line it would be easier woodwork.
dave
Thanks for that Dave.
I think I'll flog them , thinking about it, I dont't think i have the time to take on such a grand project , or achieve anything that will look professional enough.
Interestingly, I dragged a pair of speakers that I bought from a second hand shop into my listening room, I wanted to hear how they compared to the KEFS
when I tested those- these are ELTAX concept 200, and they really look the part, however , theyre rubbish ! but they was cheap, pity they dont sound as good as they look. - oops, I shouldnt condemn them, just googled them and looks like they were only £ 70 from richer sounds .
In my workshop, I have a pair of vintage " GRIFFIN " bookshelf speakers,
I'm sure the bass driver is a kef ? - they are absolutely awesome
Thanks to everyone who has responded to my posts
Adrian
I think I'll flog them , thinking about it, I dont't think i have the time to take on such a grand project , or achieve anything that will look professional enough.
Interestingly, I dragged a pair of speakers that I bought from a second hand shop into my listening room, I wanted to hear how they compared to the KEFS
when I tested those- these are ELTAX concept 200, and they really look the part, however , theyre rubbish ! but they was cheap, pity they dont sound as good as they look. - oops, I shouldnt condemn them, just googled them and looks like they were only £ 70 from richer sounds .
In my workshop, I have a pair of vintage " GRIFFIN " bookshelf speakers,
I'm sure the bass driver is a kef ? - they are absolutely awesome
Thanks to everyone who has responded to my posts
Adrian
Dave,
The company Griffin ( I think ) were located in the town of West Bromwich, near Birmingham, in the U.K.
These too were given to me from someone who was getting rid of them ( I do well with hand outs )
I think I'll list the kef units on ebay today, with some nice hi res pics.
Better for someone to use the units , rather than me thinking about what to do with 'em
re:- the eltax concept 200, they only need a pair of hi q tweeters to make them up to scratch too
The company Griffin ( I think ) were located in the town of West Bromwich, near Birmingham, in the U.K.
These too were given to me from someone who was getting rid of them ( I do well with hand outs )
I think I'll list the kef units on ebay today, with some nice hi res pics.
Better for someone to use the units , rather than me thinking about what to do with 'em
re:- the eltax concept 200, they only need a pair of hi q tweeters to make them up to scratch too
The B139 only has a 3mm xmas. It was used in t-lines by many and could only play so loud. It was beter suited to a closed box. with aperiodic damping. The B110 should have been used in t-lines to flatten out the peaks. The Audax 5' bextrene had a faltter response and never received the publicity of the B110.
Reading this thread with interest as my first decent speakers when I was a teenager were a pair of Concerto's. Bought them not long after becoming an apprentice. At that time I thought they were wonderful. I eventually made a pair of LS3/5a clones out of them as the house I was living in at that time didn't have room for the Concerto cabs. The B139's sat on a shelf for many years. After many years of listening to more recent designs it has become apparent that more modern drivers are so much better. The KEF's had so much Xover intervention to account for the bad behavior of the drivers that it literally strangled them in my view. Yes they had relatively flat responses but at what cost. Having said that I still have a soft spot for them. They were very good for their time and the R & D done by the engineers at KEF was quite ground breaking back then. My opinion would be to sell the drivers to someone who is restoring a pair of Concerto's or LS3/5a's or the like.
The B110 came in two versions. The SP1003 and the SP1057 (I think). They had slightly different characteristics and LS3/5a's using them had crossover variations to suit. Original BBC LS3/5a's were apparently individually adjusted to compensate for driver variations. It would seem that consistency between batches was a problem back then.
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