EV Woofers

[jerseydevil]

What are EV woofers and what do they have to do with Klipsch?

[dragonfyr]

Is this a trick question?

Let's see, EV woofers are quality products made by Electro-Voice.

And what do they have to do with Klipsch? Perhaps not enough...[][]

Is it a full moon tonight?[]

[jerseydevil]

I mean does Klipsch use EV components or are they simliar quality. I

saw a Klipsch speaker with an EV driver. Also, what is special about

Alinco drivers? Vintage Klipsch seem to use them.

[Malcolm]

Electro-Voice (EV) is one of many manufacturers that supplied Klipsch

with components for the Heriatage series. There were many other,

including: Stephens, CTS, Eminence, Atlas, University, Heppner, Rola, etc.

EV built woofers (12WK and 15WK, where K is for Klipsch) to Klipsch specs in

the 1950s. They were available to the public. The 15WK was used

in the Klipschorn along with woofers from other manufacturers. IIRC the 12WK was available in the 12" Shorthorn.

1960s Heresys had an EV SP12B woofer or variant in them.

The K-77 and K-77-M tweeter used in the Heritage line from the 60s on

was an EV T35A, the former having an alnico magnet and later a ferrite

magnet. After EV ceased production, to make a long story short,

Klipsch picked up the rights and continued manufacturing them.

EV built a squawker driver for Klipsch, the K-55-M, with an EV part

number of 1831-xxxx that AFAIK was never available to the public.

It had a ceramic magnet and replaced the K-55-V from Atlas that had an

alnico magnet.

One could say that all the woofers, tweeters, and squawker drivers used

in the Heritage line were of similar quality because PWK chose to use

them in his products. Klipsch used components from most of the

decent American speaker manufacturers over the years.

There is nothing inherently special about alnico magnets in speakers

except their cost. Alnico was the material that made permanent

magnet speakers viable. By the early 1970s, the cost of alnico

had soared to a point where its use was uneconomical because of several

factors. Ferrite magnets pretty much replaced alnico. Now

we have even better magnetic materials, but ferrite still pretty much

is the standard. A good engineer can make a speaker with a

ferrite magnet sound just like one with an alnico magnet.

[TheEAR]

Is this a trick question?

Let's see, EV woofers are quality products made by Electro-Voice.

And what do they have to do with Klipsch? Perhaps not enough...[][]

Is it a full moon tonight?[]

Quick to jump to uneducated conclusions are we! Go read Malcom's post and you will learn a few things.

[jerseydevil]

In other words if I find a Hersey with a EV replacement woofer that is

no reason not to buy it. That is an awkward question.

[dragonfyr]

In other words if I find a Hersey with a EV replacement woofer that is no reason not to buy it. That is an awkward question.

Indeed it is (an awkward question), and there is not an easy way to tell.

It is not enough to merely replace an "x" inch driver with another.

Ideally, the driver is mated to a cabinet optimized to the driver's Thiel/Small (T/S)- Benson parameters. The diameter of a particular driver has no necessary bearing on these.

Personally, unless you were either prepared to swap out the driver and restore an original driver, or you have listened to the unit and decided that you like it, there is no way to tell how the substitution has worked. If you are looking for a final product and are not prepared to swap it out, I would not buy it.

I do not know to what degree the T/S parameters were utilized in the design of the Hersey. Nor do I know the T/S parameters of either woofer for comparison.

Perhaps others on the site do know the T/S parameters of the stock driver.. Knowing the model number of the EV driver would allow you to source these parameters from EV. Klipsch may know, but in my experience they have not been very forthcoming with many of these specs. But again, one of the other folks on the site may have measured them or come by them in some other fashion. Such is a primary strength of such a forum as this.

And unlike another on this site who offers NO contributing information, I am simply trying to offer an educated bit of reason for hesitation, as given the limits of the information readily at hand, and especially given the original undefined parameters of your original question, there was and still remains simply too much unknown. And without the additional information, I am slow to jump to an educated conclusion!

And the reason for the "perhaps not enough" comment regarding EV and Klipsch is that PWK was primarily focused on the enclosure while opting to use 'adequate' drivers. Many aspects of the various designs could have been further optimized had he been more receptive to using exceptional drivers mated to exceptional enclosures. This became a source of some internal dissent within Klipsch that I had an opportunity to become privy too back in the 1970's. Personally, I was in what amounted to the minority camp that favored using the best drivers with optimized enclosures. The rest is history.

Hence my comment that, as EV has a history of making some fine drivers (and market competition notwithstanding), Klipsch products may have further benefited from the use of EV and/or other, better designed drivers. But this is now a moot point.

[Malcolm]

Best to buy a Heresy with the original Klipsch labelled (K-22, K-22-E,

etc.) woofer or plan on replacing the woofer with an appropriate

one. Otherwise you are playing speaker engineer. EV built

many different woofers for different applications. A replacement

would need to match, at the very least in sensitivity and nominal

impedance, and have similar or better power handling capability.

AFAIK the only EV woofers used in Heresys were the SP12Bs (K-22) used

in the 60s. They are 16 ohm units and require a Type C crossover

network. I would not be put off by an EV branded SP12B as a

replacement for one of these. But that is the only replacement

that would get an automatic OK for me. Just remember that not all

woofers that look like SP12Bs are SP12Bs.

Thiele/Small paramenters are a nice starting point for speaker

design. But that is all. It is all theory based on

measuring certain electrical and physical parameters and extrapolating

performance. Performance does not always track the model as well

as one would like. Some parameters aren't nearly as important as

one would think at first grlance. And there are important factors

that Thiele/Small parameters do not address at all. Speaker

design still requires building prototypes, measuring actual

performance, and tweaking.

The sealed design of the Heresy is amazingly forgiving. The

Thiele/Small parameters of the various woofers used over the years in

the Heresy are all over the place. Yet, they all sound remarkably

alike. The main difference is that the later woofers can play

louder at low frequencies before reaching their thermal and mechanical

limits. This is a function of power handling capability and

maximum cone excursion (Xmax).

The Heresy was designed well before Thiele and Small published their

work. Don't know whether their work influenced later Heresy

woofers or not.

[TheEAR]

"And unlike another on this site who offers NO contributing information"

I wonder who it is,does he use BLUE to highlight all his informative,helpful posts,by any chance.