SpeakerTalk

[dazm]

hi all new to keff speakers im looking at buying a pair of these ,was this a good year for these speakers and a bit of information ,thanks .


type SP1121 and are a matched pair of 5273 A and 5273 B and are 8 ohms

[suffolk2]

i would go for speakers containing these drive units

B139, BD139, B200, B110, T27

for the original kef sound

imho the new kefs dont sound the same

others may disagree

[dazm]

thanks suffolk2 , are these no good ,there from 1980's i mostly listen to jazz ,classical ,easy listning , im looking for a warm sound , a good allrounder if you can have that in speakers, im very new to this so the B139, BD139, B200, B110, T27,im not what they are , can i go by the 103,101,104 ex ex . sorry tobe a pain,many thanks dazm

[speakerguru]

This system used a B200 SP1075 woofer and a T33 SP1074 tweeter. I don't have any documentation to support this. I am just using "the force". I also seem to remember it used grommets to partly isolate the woofer mechanical vibrations from the cabinet.

A great little system. Sold by the bucket load and virtually unbreakable thanks to the S-Stop protection module. The sales guys used to plug them into the US mains to demonstrate how good it was (don't try it with UK mains ).

[suffolk2]

from the purist view, the more electronics you place in the speaker,
the more it degrades the sound, hence xovers are getting more and more simple.

as for protection circuits, once the system is connected, will it ever
be used ? so why have it there ?

[ColinR]

speakerguru said

[suffolk2]

[proffski]

This is a double edged sword.
There is much common sense regarding simple crossovers, for example group delay, phase response and many other factors.
There again some loudspeakers bass, mid, and treble units object most strongly to handling frequencies out of their allocated band.
Many KEF units such as the B139 and T27 will testify!
Witness LS35a and Spendor designs, hardly minimalist yet are firmly set in the audio history as all time classics.
If a driver is designed from scratch to work in a 6dB per octave crossover then so be it, but beware the dabbler who does the opposite!
Best left to experts and engineers who have studied the magic art at university and understand the pitfalls.

Do not get me wrong, I have designed may loudspeakers and crossovers, some were an absolute disaster and yet others a brilliant success. A combination of knowledge, study and sheer luck!
The latter hardly scientific, I started circa 1968 and am still learning and am awed by the expertise of a few established members, they could probably forget more than I have learnt and still have more to spare!

I have at work for demonstration purposes some crossovers from ATC and PMC loudspeakers, again take it or leave it but both much respected in the studio monitoring world, these are hardly minimalist.

In my private museum on the other hand I have loudspeakers with only one capacitor in series with the tweeter and sometimes with the right material they sound glorious.

Swings and roundabouts…

[centaurus]

i agree with proffski,

6db x-overs are great if you have drivers that can exceed 3x the range outside their specified crossover bandwidth. i don't believe KEF drivers were made for this purpose. I'm pretty sure the T27 wouldn't sound that great with a 6db x-over. it doesn't like going particularly low and is still sorta "spitty" with the 4th order butterowrth. it would attract bats with a 6db first order

i used to own a clean pair of bozak 302A-Urbans. they use 1st order x-overs and sounded incredible (sans the crappy high frequency response of their 200y tweeters). rudy bozak designed his drivers to effectively reproduce signals way out of their intended frequency range for this purpose though.

see ya,
Robby