KEF Puts Tweeter Inside the Woofer!!!@@@

..and Tannoy sues for patent infringement..

I don't know the statue of limitations on patent infringement but they may be too late. Kef introduced this Uni-Q design first in 1988, and it is currently in its fourth or fifth generation. I have been using their excellent 204c with Uni-Q center speaker for 3 years.

And this is news? This has been going on for decades and similar can be found in the TAD designs.

Apparently to some people; old hat to others (been using Kef Uni-Qs for the last 16 years).

I can't say if there is any differance between what their calling a ''concentric tweeter'' and what Altec called ''coaxially mounted'' but yeah, I have a pair of 804's with sectoral horns inside the 15'' woofers for about 40 years now.
I don't use em but they still look too cool to part with.

You should hook them up to an iPod just for grins and giggles.

Ya know, it'll probably overdrive the darn things
They were way too sensitive for my new power amps, once upon a time.
Their still in the original cabinets too!
Real beauts they are, all 3'10'' of it and 115lbs apiece.

I cant believe I remember all of the fine details, 102db spl@1 watt if I recall correctly, or maybe that was 10 watts but either way, too sensitive for me

EDIT: Make that 604's not 804's. I guess the old noggin is as bad as I thought it was. I can remember squat

....Make that 604's not 804's....

604E, as used for monitoring in many professional facilities. There also was a 605G if I remember correctly. Eventually morphed into the UREI 813 series and then finally died. There is currently a German monitor loudspeaker "Geithan" that has a coaxial mounted tweeter...seems to have a bunch of fans.

Steve - wait until April 1 and then you can announce that KEF finally manged to figure out how to mount the woofer in the tweeter! See how many bites you can get on that one.

I was going to post that I think the first, if not, then at least an early adopter of coax speakers was the Altec 604s. Very much in demand on the collector's market..

Haha, how about a 4-way coaxial unit?



http://www.cabasse.com/us/range/artis/la-sphere

Why was this thread (along with a couple others by Steve) even started here?!?

Take this crap over to the threads they actually belong in.

Don't mean to be a grump, but this thread should be closed.

Wanna impress me Steve? Let's see someone put the woofer inside the tweeter!

Dicey, you are indeed a grump or so it seems.

That's pretty much the way I remember it too and happy they are still worth at least what I paid for them.

The 604-8G was Altec's attempt at breaking into the ''hi-end'' stereo market. They took their best pro-monitor and dropped it into a fine looking wood box and they were in business.
It's what started me on my long speaker journey.
From those high efficiency speakers I went straight to low efficiency Magnaplaners of one model or another for the next 30 some odd years and wound up with Aerial Mdl. 9's a couple of years back. So now it's a low effeciancy box for me, but it all starts with that pro speaker.

There would be NO Ultra high-end forum to be a grump on dicey without speakers like the Altec 604 as far as I'm concerned!
So Steve missed a half century old design somehow and pointed it out, big deal. That's why a little history of how we got here to begin with is important. We all come here to learn this stuff in part, at least I do.

The high-end didn't just appear out of nowhere and alot of great, seamingly new designs are as old as dirt.



[steps off soapbox]

Hey Steve, heres another one for you to post......

"Dude in Mesopotamia invents crazy labour saving device, and calls it...... The Wheel".

Klipsch did this like 30 years ago or more

They did? Klipsch?

Hey did you guys know that we won't have to watch VHS anymore? Something called the Laserdisc is coming out soon!!! Seriously though, I don't know how any supposed audiophile could not know about Kef's Uni-Q!

Put some wings on that and it would look like something designed by Ed "Big Daddy" Roth.

Hi

Long time no post ...
The concept is very old and has been used in several speakers. My dad had two different models from the old Lafayette Stereo Catalog; one ofthese was the SK-500 a 12 inch woofer with a compression tweeter mounted co-axially .. back in the 60's ... I am almost certain Tannoy has no patent on this as these were common back then ...

Frantz
presently in the USA

True, there used to be quite a few coaxial speaker arrangements. If I remember correctly, what Tannoy did that was unique was to have the woofer cone flare act as an extension horn to the the coaxially mounted tweeter. If they did have a Patent on it, it's long expired. KEF, TAD and Thiel all have expoited this basic concept. The KEF Reference 20x/2 high frequency driver is a particularly good implementation. Look at the smoothness and uniformity of the 207/2 on and off axis frequency response plots over at Stereophile. About as good as it gets.

Yes a friend of mine who owns a company that outfits Theaters has a pair still. I cannot find them on the net I will ask what they were called. From what I remember and I could be wrong this was 20 years ago he told me they were made specifically for the movie earthquake. I have never seen it

RCA's speaker designer Harry Olsen's LC-1A was a 15" woofer with a concentric tweeter designed and sold in the late 40's and 50's.
Great speakers that I grew up with...still around and working well today.

Maybe we do need the history lesson...

The Altec Duplex is arguably the most famous speaker driver ever made. It remained in continuous production from 1943 to 1998 and set the standard for critical monitoring applications. Through the 1950's, and into the 1970's, the 604 was used by more recording and broadcast studios than all other monitor systems combined.

Altec Lansing's famed 604 was not the first Duplex® coaxial speaker; that honor goes to the company's 1941 model 601, which mounted an HF compression driver onto the back of a 12-inch woofer with a hole cut into the center of the magnet, forming a throat for a small multicell horn in the center of the cone. However, it was Altec Lansing's model 604 coaxial that created a splash that continues to this day. The 604 was based on a 15-inch woofer with a 3-inch voice coil within an Alnico V permanent magnet, combined with a large HF driver and a six-cell horn. The 604 was capable of a then-impressive 30 watts of power handling, but due to its high efficiency, wide bandwidth and point-source imaging, it was soon adopted as a standard monitor in studios.

That is pretty much the story but some other very interesting stuff on early speaker development can be found here http://www.audioheritage.org/html/pr...tec/duplex.htm
amongst other various sites on the web and of course, Wikipedia.
http://en.wikipedia.org/wiki/Studio_monitor

This concept goes back to the 1920's. The patent was filed in 1928

Mechanical coaxial speakers have existed for many years. I own a set of Western Electric 10" speakers from the '40's with a cone constructed so that the center portion was lighter and reproduced the higher frequencies, while the outer cone was heavier and reproduced the low frequencies. While the frequency spectrum was not divided electrically as later two-way designs, they were nonetheless two-way concentric speakers. The concept is very old, and I'm not sure when the first practical 2-way design using separate transducers appeared, but I'm pretty sure it predates the Altec Duplex. It was a great speaker for sure, but probably not the first of its kind.

I have had a pair of Tannoy Monitor Gold's (in enclosures of my own design) in continuous service for the past 40+ years. They sound as good today as they did when I first heard them. Of course, the days of my acute hearing is long gone.

Bob