Article: The Patrician (Flyer and Construction Article)

[WMcD]

Attached to the next frame is the 1955 Audio Magazine article on the Patrician and a sales flyer.

Gil

[WMcD]

Notice the front page of Audio says the article makes building "easy".

Have you ever noticed that just about everything sold at HD has some language saying "easy to install." Of course not all is easy to install. The Patrician hardly looks easy to build.

Also, note that the 18 inch woofer driver cost $90 in 1955 dollars. That must have been prohibitive.

Smile,

Gil

Flyer and Construction Article on E-V Patrician.pdf

[sunnysal]

thanks gil, I see what you mean by "easy" way beyond my abilities! tony

[formica]

Thanks Gil... it's the first time I got to peak at the inner workings of the Patrician. Has anyone here ever auditioned one?

I noticed that the marketing dept didn't quite influence FR curves as much back then as now... showing an honest 4000Hz peak and true LF and HF rolloff. Easy build? Ok, I understand where they were concentrating their efforts at...

Rob

PS: Opps... just noticed the FR curve is part of the "Audio" article...

[ZAKO]

Formica......Yes I auditioned the Patrition Khorn In downtown St Louis. A piano store named Aeolian. They had a audio store upstaires. I still remember it sounded pretty good. But its size was BIG. Down the street was another store Van Sickle they had The Klipschorn. This was a long long time ago. Both stores are gone now. Down town St Louis has changed & not for the better. I was a young TURK then. Couldnt afford spit. But now Ive got my Khorns. And the EV Patritions are a dim memory.

[mustang1]

Gil, is this your next project, just for fun?

[WMcD]

I went through St. Louis a several times on business some years ago. The downtown area was at a nadir and just turning around. I trust thing have gotten better.

I saw Catfish and Crystal from the outside. Later I learned it was a restaurant of some fame in its day. It may show that there is newer enterprizes but much of the "old class" is displaced.

- - -

No, this is not my next project at all.

I just wanted to research what was going on and gather data. I.e. is this a super K-Horn? People ask about scaling up, and scaling down. Why did alternates to the K-Horn not proliferate? Certainly PWK could have built whatever pleased him.

It looks to me that when EV scaled up, they didn't gain more bass even though common engineering logic dictates they should have because of a lower Fc and bigger mouth size.

At the same time they ran into more poor hf response of the bass horn. To compensate they needed an even more complex treble set up. So the project created more problems than it solved and at increased cost.

- - - -

I'm also taken at why there were not more designs along the lines of the Jubilee in early days with multiple bass drivers solving some of the folding problems. Call it stacked LaScala facing into a corner. The ancients did not lack such insights.

It looks to me that the cost of bass drivers was high, and cost of precision woodworking labor relatively low. So, for example, the complex Hartsfield (I and II) were more cost competitive. All sorts of schemes to avoid the cost of an extra bass driver.

Naturally that cost accounting does not hold sway these days.

Gil

[bkrop]

Thanks Gil, for taking the time, and making the effort, to post another interesting article here!

[lynnm]

Great reading but from what I gathered from the article and plans a factory built Khorn was the better buy by far.Building a Patrician from scrach was obviously not for the inexperienced or faint of heart enthusiast.

The Chicago Main Library looks to be a treasure trove of information about early audio.

Keep 'em coming mi amigo! I look forward to your contributions every week.

[v3spitfire]

My uncle still has the Patrician, but its the Patrician 800, not the one pictured. It uses the 30 inch woofer as opposed to the 18 inch mentioned.

I have a copy of the owners manual, which states it goes down to 15 cycles.

I haven't heard it in 5-6 years, but with his MC240 and various Mac preamps, it really sings with no effort. Truly no sub is needed with those. He pairs it with a Stereon 850, which shares the same upper drivers, without the bass horn (goes down to 100). He bought all of his stuff new back then and kept it all.

[formica]

Actually i was kinda surprised by the 200Hz crossover.

Given that the Khorn crosses over at 400Hz.. was EV simply more conservative in choosing it's x-over, or was their woofer not up to par?

BTW, here is another brochure...

Rob

[formica]

sorry for the multipart post... but i don't have Acrobat on this machine...

[formica]

Maron, do you recall any benefits to the larger horn?

I know the specs don't tell half the story, but there doesn't seem to be a justifiable performance gain...

[formica]

Last file...

Rob

[WMcD]

I suspect that EV was running into two issues which theory predicts.

One is that the folding creates issues of path lenght around the bends and the change of geometry in the second, front to back switch from horizontal to verical orientation.

This just how well the horn works at HF to pass sound pressure from the throat to the mouth. The bigger it gets, the more these affect HF. The path issues get larger as the horn gets scaled up. Hence less HF no matter what is being used to drive the throat.

The second is the bigger mass of the driver diaphragm. The motor can create only so much force. The available force is taken up by moving the larger mass of the bigger diaphragm. So the pressure available at the throat is poor too.

As you can see, scaling up has created two problems. The horn itself is lossy at HF. The driver is lossy too. The solution used by EV is more horns, as I mentioned.

Gil

[formica]

----------------

On 4/24/2005 3:36:21 AM William F. Gil McDermott wrote:

The bigger it gets, the more these affect HF. The path issues get larger as the horn gets scaled up. Hence less HF no matter what is being used to drive the throat.

----------------

Interesting... shows you how much i know about horn physics. So the don/greg's mini khorns may actually have an improved upper frequency response?

[WMcD]

I'd think there is less of a problem.

A simple issue is the turn. Say the first one in the K-Horn and the only one in the LS.

The theory is that the inside of the turn has a zero radius and path lenght. The outside has some distance. So the pressure wave travels different distances and they get out of phase, and partially cancel out each other.

I'm not convinced that any analogy is correct, but the path lenght thing is one way of looking at it. The "reflector" when present, may help. Assuming help is needed.

You may have seen Mr. Fritzmaurice' (sp) designs in AudioExpress. He is a big advocate of using a curve on the outside rather than the more crude reflector.

I don't particularly like Bruce Edgar's diagrams which show little wavefronts and the "reflector" acting like a mirror. I think the wavelengths are too large to be modeled like that.

I also question his inductor theory, partially. It is closer to what I think. That is that imperfect bends are just a short discontinuity in the acoustic transmission line. Since transmission lines can be modeled as caps and inductors, we are pretty close.

But going back to the smaller is better thought. This is one reason for the bifurcated path in most Klipsch products. We have two small bends rather than one large one. Someplace in the literature there is a comment that the K-Horn has two paths to maintain HF response . . . without more explanation.

OTOH, the Valerie works okay with one big bend at the bottom. The Voight horns have a big reflector at the top. Maybe these work as reflectors because they are indeed larger. Plus, we're out of the high pressure area and near the mouth.

Best,

Gil

[DizRotus]

In the early 70s, it was my good fortune to meet PWK at a seminar put on by The Stereo Shoppe of East Lansing, MI. He was explaining the shortcomings of Klipschs short-lived experiment with licensing its designs to Electro Voice. In mid syllable he asked me, Do you know what a Patrician is? Before I could reply that it was an EV speaker, he continued, Someone who steps out of the shower to take a leak.<?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" />

It was an amazing experience. He was the real McKlipsch.

[D-MAN]

Gil done good.

Interesting that the concepts concerning horn folds have not changed in 70 years...

The benefits of the Huegen waveform reflections as discussed in the Edgar paper would most readily be valuable in reflecting smaller-length waveforms, as Gil stated above, although Edgar reports that it was beneficial on low freq waveforms, also. It should be noted that there are VERY FEW successful folded midrange horns (that is above 500Hz Fc). If the Huegen approach was indeed workable, it would seem to me that there would be more folded mid-range horns around, but that's just my theory.

The radial turn approach is also referred to in horn documentation as being particularily desirable.

A non-radial turn (i.e., a straight reflector) can be thought of as an "averaging" tool for a full radial turn.

As with all of the straight planar elements (i.e., plywood)used in typical bass horn construction, there are NO true exponential (or anything else) expansion curves, only approximations formed by planar elements. Yet we find that in most cases, the approximations are "close enough", performance-wise.

I would think that the Huegen-inspired reflector would be rather frequency-specific, that is, effectively reflecting a very narrow bandwidth and not-so effectively reflection others. However, the important point is that IF ANY portion of said bandwidth is more efficiently turned without degradation, the better the overall output frequency response of the horn. This can be adventageously used when trying for a higher crossover point. Howeve, it is apparent that it HAS to form a constriction of the horn path, and THAT would theoretically cause backward reflections, one would assume. I've always stuck to the PWK radial average approach as seen in the Khorn. Interestingly, I believe that PWK went with the Huegen approach in the Jubilee in the tail-board area, but NOT the 90 degree front turns. Hmmmmmmmm....

Take the ducted port. It doesn't transmit waveforms along its length. It is a volume of air that moves equally on each end. Essentially a vibrating volume of air bounded by a duct acted upon by compression and rarefaction at one end. These require an equal area on both ends, whereas the horn is smaller on one end and larger on the other (length and other considerations notwithstanding). Essentially, the same applies to each. So, the question is, does the horn actually transmit the waveform along its length or is it a moving column of air as with a ducted port or pipe-form?

Air column vs. waveform propogation. Both horn theories are apparently quite workable.

DM

[WMcD]

I think D-Man and I are on the same wavelength. Ahem.

The horn does act as a ducted port down near cut-off. The mass of air, or at least the part near the diaphragm starts acting like a slug of air. This is why the mass reaction at the throat goes up as you go down to cut-off. A bigger and bigger slug is attached or influenced as the rate of driving movement goes down.

With finite lenght horns with small mouths, the reactace goes positive and negative near cutoff. I think that is partially because of mouth reflections. Some air may be being sucked out the mouth.

This also indictates that small mouth horns can't benefit from reactance annuling. The reactance is already negative, or capacitive, in some locations in the frequency and they'd get worse. Note that the typical advice is to set resonance at or above cut off. PWK puts it well below cutoff. I'm quite sure that is simply to bump up response. He is not reactance annulling.

At higher frequencies, the horn does act like a tube without reactance. There is an alternation of pressure and volume velocity which cause propagation. Because there is propagation, there is not an attached slug of air. It moves on down the line.

- - - -

I like the transmission line analogy. I've set up Spice models for Olsen's finite horns by the use of sucessive transmission lines with electrical impedance set to the acoustic impedance of the horns he illustrates. The velocity or delay in the lines is the speed of sound. Baranek has some circuits for mouth impedance.

The model worked well in that impedance (real and imaginary) at the throat is exactly as he predicts.

One exception is that there are a few more squiggles up at the high end. Dr. Leach used a Spice model to do a pure math calculation of the impedance transfer based on Olsen's equations. His model showed the same squiggles which my model did. So I assume Olsen was just showing an approximation up there. Its a lot of math.

This also works if you model the sections of the line with just inductors and capacitors. At the time I had a student version of P-Spice which only allowed two TX lines, but unlimited numbers of caps and inductors.

= = = =

I think there are folded midrange horns. These are the re-entrant bull horn types. The two 180 degree turns are as narrow as possible because the turn takes up the entire circumfrence. It is as if we're dealing with paths that are rings.

= = = = =

It is interesting to note that the Bell Lab bass horns might be re-entrant types. I'd put up an old Radio-Electronics article on bass horns last week. One seems to be a rectangular re-entrant. The described planetarium bass horn might be too. The Jubilee at the 180 degree turn in back, looks a bit like these depending how fuzzy your thinking can be.

Best,

Gil