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‘Unbeatable’ Kalman reviews KEF

Mnyb

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Can you think of any technical reason why that would be (specifically restricting comment to the coaxial driver’s contribution)?

The LS50 as a full range will obviously sound far less capable in the bass regions.

Otherwise, if the coaxial drivers are much the same unit, the most likely explanation would be the good old sighted listening effect.

cheers
it's not really the same UNI-Q the ones used only for midrange has other optimizations for example the surround of the driver is much flatter and possibly many other diffrences as it is a true midrange driver and not a midbass .
 

thewas

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it's not really the same UNI-Q the ones used only for midrange has other optimizations for example the surround of the driver is much flatter and possibly many other diffrences as it is a true midrange driver and not a midbass .
Also the LS60 Uni-Q is smaller 4" vs 5.25" for the LS50.
 

DSJR

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I wonder how Kal would review that!
No idea, but I loved these speakers in 'ab' form (too shrill toned in the original version) and they're perfect for smaller rooms in a near to mid field environment. The B139 in ABR form flopped about too much with vinyl, but come the digital age, these then old boxes sprang to life in a small room and the very slight 'hollow character' of the B200 bass unit (in all the 70's boxes using it) was never ever noticeable if they were heard singly away from a dem room wall-of-speakers. The foam grilles crumbled decades ago but cloth and maybe crude foam replacements may be got now. Back in the mid noughties I was offered a pair in good nick for seventy five quid. I believe they fetch a lot more than that now...

I think KEF chased sales and marketing too much in the 90's onwards, tailoring the sound even of some Reference models to stand out in a mass-speaker dem (the ones with 'sssssssooooooper tweetersssssssss' all but stripping paint I remember, but it seems nowadays, proper objective design prevails once more - thank goodness.
 

fpitas

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No idea, but I loved these speakers in 'ab' form (too shrill toned in the original version) and they're perfect for smaller rooms in a near to mid field environment. The B139 in ABR form flopped about too much with vinyl, but come the digital age, these then old boxes sprang to life in a small room and the very slight 'hollow character' of the B200 bass unit (in all the 70's boxes using it) was never ever noticeable if they were heard singly away from a dem room wall-of-speakers. The foam grilles crumbled decades ago but cloth and maybe crude foam replacements may be got now. Back in the mid noughties I was offered a pair in good nick for seventy five quid. I believe they fetch a lot more than that now...

I think KEF chased sales and marketing too much in the 90's onwards, tailoring the sound even of some Reference models to stand out in a mass-speaker dem (the ones with 'sssssssooooooper tweetersssssssss' all but stripping paint I remember, but it seems nowadays, proper objective design prevails once more - thank goodness.
I never really noticed KEF until recently, when I saw the performance of their coaxial driver. Few, if any other coaxial drivers are that seamless. Gotta admire competent engineering.
 

DSJR

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I never really noticed KEF until recently, when I saw the performance of their coaxial driver. Few, if any other coaxial drivers are that seamless. Gotta admire competent engineering.
I swear - they weren't always like that, but then I didn't know back in those days that slightly off-axis they could be better. The early Uni-Q drivers didn't integrate as well as they obviously do now, but the late 90's reference models were really nice sounding, if a bit 'bulbous at the front'...

Back in the 70's, they had a class leading range of speakers and another vintage model I remain firmly addicted to is the three way Concerto, which is a bit 'wide' for modern living (the Cantata replacement turned the B139 bass driver to vertical which slimmed them down a bit). Most users sat them on the floor but they 'sounded' so much better raised 10" or so off the floor. Apologies for the digression ;)

The coffee-table book about KEF is well worth a read, as is the Quad one by the way.
 

raindance

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Sure, I've heard them but so long ago I cannot even recall the event. I was a KEF fan way back in the mid-60s but was too poor to buy such things. They did inspire me and, from the mid-60s through the early 90s, built many speaker systems based on KEF and, later, IMF and Linkwitz ideas.
I still recall how impressive the "big" IMF transmission lines sounded on classical music. My electronics lecturer at college had a pair in his apartment pushed up against the wall (not much space). They were really unfussy and had tight, deep bass.
 

Kal Rubinson

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If one bit of hypberbole equals US$2000, then 16bits should me more than enough for anyone. I certainly can't afford 24 bits of Sterophile hyperbole.
With hyperbole, it depends where you are on the curve. :)
 

Kal Rubinson

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Can you think of any technical reason why that would be (specifically restricting comment to the coaxial driver’s contribution)?
No. The substantive differences are in the upper bass/lower midrange as the LS60s fill in where the Uni-Q's power wanes. OTOH, I am pretty sure that, in a side-by-side comparison, one might discern the effects of the LS50's Uni-Q handling bass on all its sub-HF output while the LS60w's Uni-Q is spared that burden.
I still recall how impressive the "big" IMF transmission lines sounded on classical music. My electronics lecturer at college had a pair in his apartment pushed up against the wall (not much space). They were really unfussy and had tight, deep bass.
Yes, I recall my own take on the IMFs fondly.
 
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mhardy6647

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I still recall how impressive the "big" IMF transmission lines sounded on classical music. My electronics lecturer at college had a pair in his apartment pushed up against the wall (not much space). They were really unfussy and had tight, deep bass.
The little IMFs were pretty darned impressive as well -- based on a pair of SuperCompact II that resided at my house for a while.
Sensitive and easy to drive, too.

I only passed them along to someone else because the MR surrounds were failing and I just didn't want to deal with sourcing appropriate replacements for them.
 
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