2397 Wood Horn

[Chas]

Before I install 2311's with my newly re-diaphragmed (2441 parts) 2440's (thanks again, Giskard!) into my DIY 4333's, I decided to spend the weekend listening to a pair of 2397 wooden horns perched on top of the enclosures with the newly resurrected drivers. I am very impressed, to say the least.

I am unsure what is contributing to the sound qualities I hear. I have never had this driver or this horn running in my system.

I notice a slight lack of "bite" compared to a 2420/2312/2308 set-up - but man oh MAN, the midrange is to die for!

What's the scoop on the 2397? I see it referred to sometimes as a "Smith" wood horn. I would love to hear about the history or any info about it.

Anyone know? Is there a tie with Westlake here somewhere?

[Steve Schell]

This type of horn, often referred to as the "Smith horn" of the "flat horn" was invented by Dr. Bob Hugh Smith, a professor at U.C. Berkeley. Dr. Smith was very much a part of the postwar west coast hi fi scene, and made several contributions to the art. His article "A Distributed Source Horn" , which contained full construction plans, was published in the January 1951 issue of Audio Engineering magazine. Please email me privately at [email protected] if you would like scans of this article.

The DSH is basically an exponential horn where the expansion is all contained in the horizontal axis. Dr. Smith designed the horn so that there would be a widespread apparent source of sound, which he felt would provide a better listening experience than the pinpoint source of most horns. Another goal was ease of construction. There were many DIY horn builders back then, and the DSH was quite popular for awhile.

JBL eventually introduced their version, the 2397, and Westlake Audio built many speakers with DSH horns as well. I've never quite understood this, as DSH horns usually sound fairly pinched and nasal to me compared to most other horn types.

[Mr. Widget]

Originally posted by Steve Schell
I've never quite understood this, as DSH horns usually sound fairly pinched and nasal to me compared to most other horn types.

That is exactly the opposite listening experience from what I have had. I have discovered that due to the wide dispersion side wall reflections can destroy imaging, but in a room with controlled reflections they image extremely well and I find the 2397 to sound more natural and un-horn like (nasal sounding being a typical complaint about horns from non horn enthusiasts) than every horn I have tried to date.

Steve have you listened to the Westlake or the JBL 2397 or has your experience been with DIY DSH horns? From reading the article by Dr. Smith there are differences from the horns described in his paper and the production units produced by JBL and Westlake. Most notably the use of the 2328 throat adapter.

Here is a thread where I show some pics of some of these horns that I have made.

http://audioheritage.org/vbulletin/showthread.php?s=&threadid=695

Widget

BTW. Thanks again Steve for sending me that scan. It was fun reading.

[Chas]

Very interesting and thanks for the info Steve and Mr. Widget.

I notice that in the JBL literature they have fairly substantial rising response compared to say, a 2311. This may be part of the attraction for my ageing ears.

I am so taken with the sound of the 2397 that I'm contemplating a new ground-up 3 way design incorporating the horns, maybe even a nice Widget pair if they're still available, mine are really ugly...

In a three way set up, where would you mount a 2405? I am thinking about the consequences of HF diffraction off the horn flare if all the drivers are arranged in the center of the baffle. Maybe I could offset the tweeter and have it mounted above and to one side of the horn where the protusion of the flare is less. Food for thought, I suppose.

I guess this is one of the reasons for Westlake using a similar, smaller horn for UHF, rather than a vertical slot loaded design.

[Don McRitchie]

I don't know how the following translates into sound reproduction. Last time I was in L.A., Dr. Bruce Edgar did a simple and intriguing demonstration for me and Steve Schell using the 2397 vs his tractrix horn. Basically, he used the horns like megaphones, speaking just behind the horn throat. Coming out of the tractrix horn his voice sounded natural, only louder. Coming out of the 2397, his voice was very noticably coloured. Again, I cannot state that this is representative of how the horns would react to compression drivers since I have never heard a 2397 used in a system. However, it was an interesting demonstration.

[Mr. Widget]

Interesting Edgar comparison. One of the people I made horns for also has the Edgar salad bowls. Here is a quote from his comparison of the two when using 2441s on both horns.


"WOW! Very smooth sounding! Compared to the Edgar horns, they are less
upfront sounding with a more uniform dispersion pattern. The sound does not
change from side to side listening positions. Did I mention how smooth they
are??"

But then again we all do hear things a bit differently. I like the Tractrix horns from Dr. Edgar. I also like the 2397. I especially like the esthetics of the Westlake as well as their sound.

Chas, to my ears the improvement between the 2441/2397 compared to the 2420/2307 is nothing short of phenomenal. As for slot placement... I have not found the ideal solution for that when aesthetics is a concern.

Widget

[Steve Schell]

Hi guys,

My experience with the DSH has been confined to a couple of Westlake demos at trade shows, and a listening session at Bruce Edgar's one time. On that occasion, I had brought a mint pair of 375s on 2397s to trade with a friend of Bruce's for some Lansing field coil gear. We removed one 2397 and installed one of Bruce's 350Hz. tractrix horns, then installed that combination on one side of Bruce's Titan system, and the 375 with 2397 on the other side. It seemed no contest to us on that day that the tractrix horn was more open and natural sounding.

Many factors are probably involved in our differing experiences; crossover, room acoustics, etc. The DSH has been popular for more than 50 years now, so there must be more to it than meets my ear. There have been hobbyist systems built in the past with DSHs covering more than one frequency range. I spoke to one fellow who had a pair of speakers, built in the 1960s, with lower mid, upper mid and tweeter DSHs.

[scott fitlin]

There was a club in NYC called Paradise Garage that used both 2395 lenses and the 2397 "Smith " horn. The 2397 was right ontop of the lens, and the mids were split into 2 sections!

I liked the wood horns, although they could get a bit nasally sometimes. But I liked the wide dispersion, without the center hotspot, like the 2395 lens has. What the wood horns do thats right is tonality. Wood, unlike metal, and sometimes fiberglass as well, doesnt ring, and has a sound that is natural and doesnt bite. And of course the wide dispersion horn doesnt beam, so the image is stable as you move around the room. TAD still makes wood horns, and Westlake uses wood horns, because of their natural sound characteristics. Thats what its all about as far as Im concerned.

My only negative comment on wood horns, particularly for pro use, is that they change sonically with the temperature and humidity. At home this isnt a problem, but in a club with 2500 people or at a concert it is!

:cool:

[Hofmannhp]

Originally posted by Mr. Widget
That is exactly the opposite listening experience from what I have had. ......and I find the 2397 to sound more natural and un-horn like (nasal sounding being a typical complaint about horns from non horn enthusiasts) than every horn I have tried to date.
Widget


Hi folks,

I agree with Widget (as he knows from earlier threads) and I like the sound of the 2397 specialy with a 2441 a lot. In comparision to other models like 2312/2308 or 2309/2310 and 2395 the 2397 is my vote for an "unhorn" sound.

HP

[Chas]

Okay, I have to admit that based on my experience for example, with EV horn loaded stuff, diffraction = nasal sounding.

Plus, after many years of listening to lots of different kinds of speakers, particularly panel types, my ears are particularly sensitive to both boxy and nasally midrange colorations.
On the 2397's, I don't hear a nasal coloration, I just don't hear it!

There is a transparent, electrostatic quality about them. Once I get the 2441's and 2311's installed in my boxes, with suitable bracketry, I will try the 2397's with my 2420's and some 2327 adaptors. Then, maybe I can compare things with a little more sanity.

[Mr. Widget]

Originally posted by Chas
...I will try the 2397's with my 2420's and some 2327 adaptors. Then, maybe I can compare things with a little more sanity.

I have tried the 2420 with 2327s on the 2397 horn. I was very disappointed. I guess you might say the horns sounded rather "nasal". They certainly didn't have the smooth natural quality of the 2397 and 2441. Also in regards to the plot of the 2397 output in the JBL literature. That rising response to 10KHz with a sharp drop off is the result of using the 2440 driver. The 2441 has a much smoother response.

Widget

[Chas]

Sure, Widget, go ahead and burst my bubble!:biting:

So, you're telling me I have to buy another pair of 2441's to do a real A-B comparison? Geez, there won't be anything left for the donation this year to my Mutual Funds!
:D

Seriously though, the literature I was looking at regarding the freq. response, was based upon using the 2440 driver.....so I am at a loss to explain the differences except for the influence from the horns themselves.

BTW: I haven't had this much fun with Audio for a long time.......
:smthsail: second BTW: I love your version of this horn too.

[scott fitlin]

Originally posted by Chas
Sure, Widget, go ahead and burst my bubble!:biting:

So, you're telling me I have to buy another pair of 2441's to do a real A-B comparison? Geez, there won't be anything left for the donation this year to my Mutual Funds!
:D

Seriously though, the literature I was looking at regarding the freq. response, was based upon using the 2440 driver.....so I am at a loss to explain the differences except for the influence from the horns themselves.

BTW: I haven't had this much fun with Audio for a long time.......
:smthsail: second BTW: I love your version of this horn too. If you have 2440 drivers, just change the diaphragms to 2441 diaphragms. Thats the difference between the two, and IMHO, the 2441 phragm sounds alot better than the 40!

And the 1in drivers always sounded somewhat nasal. 2in is THE way to go! If you got the 2397,s get the best from em with the 2441!

:cool:

[Maron Horonzakz]

Ive been using the 2397/2328 on the JBL 2450 with good results for the last 15 yrs. Ive switched to the 2450SL diaphrams & they even sound smoother like using aluminum But longer lasting. I had a smaller Smith type horn using LE 85 for the top end . It was only 10" long. But the throat was not designed right So I abandond that for 2405. I find the smith more open . Ive heard several Smith DIY made mutch LARGER crossing over at 300hz using 2482 drivers , It was smooth & tansparent.

[Alex Lancaster]

Hi there:

What do You think of the following possibilities that I have:

2441's
2445's
2446's
TOA 2" horn drivers, 3" diaphs.

2311/2308´s
2382A's

2441 diaphs.
2445 "
2445 non JBL diaph´s
2450 diaphs

The iterations are many, many, suggestions?

Alex.

[4313B]

I'd dump it all and pick up a couple pair of L100's...

[boputnam]

Originally posted by Giskard
I'd dump it all and pick up a couple pair of L100's... :yes: :yes: :yes:

[Alex Lancaster]

I´ll have to wait and win the raffle.

[4313B]

Ah! :p

[scott fitlin]

:confused:

[4313B]

Hi Scott :)

You have to know we are just screwing around. We can't allow every single thread to be a veritable plethora of sage advice and spot-on technical discourse. ;)

"The iterations are many, many, suggestions?"

I just thought it might be helpful to narrow down the number of iterations by simply dumping the whole list and getting some L100's instead. They are the bomb and two pair go great with something like a Marantz 4300 Quadraphonic Receiver.

[scott fitlin]

How can you take me so seriously? I have a sense of humor too! After all, Im the guy who still likes TLO84 chips, so I am a comedian too!

:nutz:

[Maron Horonzakz]

Medication? or Booze.

[scott fitlin]

Originally posted by Maron Horonzakz
Medication? or Booze. Audio did it to me!

:wave:

[Robh3606]

Hey Bo, Giskard too

Saw this figure you guys can draw straws to see who bids!

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=61377&item=3093996933&rd=1

What a great deal!!


Rob:rotfl:

[boputnam]

Just think what those cabinets could be used for...!! :hmm:

And, Giskard, that is (I think) one of the most hilarious posts, ever. Quadrophonic Marantz... Pretty soon you too will be shipping obscure blue paint all over the planet... :rotfl:

[4313B]

A Buy It Now price of $775??? :eek:
I wouldn't pay less then $1,200 so the deal's off. :no: