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Jim Hodgson
12-09-2011, 06:21 AM
Hi folks ... brand new here and have a question.

I'm on a quest to slowly put together a full-range horn system by converting my Altec Carmels (drivers = 2 x 414Z 12" woofers / 804A 1" compression driver) into something much better sonically. I'd kind of like to go in steps in order to experience what each improvement adds to the mix (i.e., I'd like this to be as much a learning exercise as a consumer exercise). I think step 1 is to replace the aluminum 811B horn with a wooden horn -- maybe a 2397??? I'd use my 804A compression drivers with adapters for now; but, step 2 is probably to replace those with 2" CDs.

I've never heard the 2397, but I think they would likely better my 811B horns, which are too directional. (They leave both my GF and me kind of dissatisfied when we listen together -- which is often. I hear the left speaker, she hears the right, and we're forced to compare notes later ... or something like that.) Even when listening solo, I notice how severely the soundstage collapses when I shift my head a foot or so right or left.

Might these be it ... or is there another horn design that would improve upon my current aluminum horn and better suit two listeners side-by-side at a short listening distance (~10 feet)?

Thanks for your thoughts!

Lee in Montreal
12-09-2011, 06:46 AM
Hi Jim

What I like with 2397 horns is that they don't sound like horns at all. In fact, they are quite transparent and relaxed. You don't get the metallic resonance you usually get from an aluminum horn. The diffraction is also very wide and the sound is well distributed, wherever you are in the room. I'd say go for it.

Mr. Widget
12-10-2011, 11:32 PM
I too like the 2397. It is generally free from a horn sound if crossed over high enough. I definitely prefer it with a 2" driver. In my opinion there are two issues with the 2397. First, it does have a very wide dispersion pattern that needs to be controlled in the room. The other issue is that they don't have "audiophile" imaging... but then I am not aware of any other vintage horn based systems that do. This isn't usually problem as most people who are drawn to these vintage systems aren't looking for that type of sound anyway.

I don't know what you are after sound wise and system complexity wise, but I do think a sub below a single 414Z, a 2" driver on the 2397, and a Fostex super tweeter or a JBL 2405/077 up top would give you a very commanding system. If done right it could rival a JBL 4345.


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Maron Horonzakz
12-11-2011, 08:11 AM
I believe I may have the oldest Smith Horn (pre 2397) on this forum,,Made in 1951 and derived from the Audio magazine construction article...Its 35 inches wide and now uses the JBL 375 driver,,I plan to install a new Truextent diaphram in the near future,, As soon as funds become AVAILABLE after the first of the year,,,,At present it sounds very natural,,,Remember it was designed before STEREO,,, So spacial imaging was not important,,,Ive made a small version to use as a tweeter,,useing a Eminence APT-50 super tweeter strapped to the small Smith type horn.. It blends very well.. All sitting on top of a Klipsch bass horn..

Lee in Montreal
12-11-2011, 08:14 AM
Hi Vlad

Would you have any picture of your 35" wide horn? Does it have a tall mouth, or is it shallow like the 2397?

Maron Horonzakz
12-11-2011, 03:46 PM
THE SMITH HORN VERT, IS 2" tall..No i dont have a picture...The horn was made by George Ashworth,,,A close friend of Paul Klipsch,,, Paul came up to St Loius to see and hear the Smith Horn.. But PAUL KLIPSCH wanted a cheeper way to manufacture a HF Horn..At that time Ashworth used the University HF driver,,,THe same driver Klipsch eventually used,,,I recommended that Ashworth use a JBL driver...I loaned him my JBL 375,,, He made the transition horn adaptor to fit the driver to his horn.. I still have the cardboard templates for the septa vanes,,and the plans to the transition adaptor..Ashworth made several Smith Horns,,,Even larger,,,After his death I recieved Two,,and a friend of mine has the other two...BUT Ashworth did not use them as a Stereo pair,,,He was a dedicated MONO AUDIOPHILE ,,,HE had a system in his living room 18x30 feet and another in his down stairs lab..

Lee in Montreal
12-11-2011, 03:55 PM
There's a bit of audio history right there ;)

Thanks for sharing.

dubkarma
03-09-2012, 12:53 PM
Using the BMS 4590 coaxial compression driver with the (cheapo) BMS passive crossover @ 6500 Hz, so far I like Lee's 2397 repros better than a pair of TAD TH-4001 repros and a pair of Azura horns.

On the other hand, this is the first time I've used the Bryston 10B crossover (@ 800 Hz) instead of the old JBL 5235 (also @ 800 Hz).

A McCormack DNA-500 drives the LF speakers (TAD TL-1603 in 30 x 20 x 19 in. cabinets tuned to 32 Hz) and a Bryston 4B-SST2 (attenuated by 15-16 dB) drives the horns.

My greatest surprise is, as Lee has already stated, that the 2397s sound very natural without any of that "man in the well" sound I got with the other horns. I think, though, the cabs should be raised four or five inches to get the horn at optimal height. And, though it's too late now, I think I should have placed the bass driver higher in the cabinet. . .

But. . .I'm new at this game, so I guess I have to go back and try the other horns with the Bryston crossover. . .55023550245502555026

Lee in Montreal
03-09-2012, 12:59 PM
Nice... Now all you're missing is a nice set of 2404 or 2405 ;-)

dubkarma
03-09-2012, 01:38 PM
Nice... Now all you're missing is a nice set of 2404 or 2405 ;-)

Hi Lee,

Actually I've got a pair of 2405s with 10 kHz passive crossovers and also those 2405 brackets. But with the BMS drivers, there's no need for a 2405, as they are "compound" drivers, with a 1-inch compression driver, crossed over at 6500 Hz, coaxially mounted with the 2-inch driver.

In any case, many thanks for providing the 2397 kits! For some reason, the cabinetmaker found it rather challenging to assemble them, but in the end he did a good job, including making a simple, but very solid, pair of mounts for the drivers and horns.

pos
03-09-2012, 01:45 PM
The 2397 absolutely needs a tweeter, for directivity reasons, above ~7khz

dubkarma
03-09-2012, 02:16 PM
The 2397 absolutely needs a tweeter, for directivity reasons, above ~7khz

That's why decided to try the BMS 4590, because it combines MF (800-6500 Hz) and HF (6500-22000 Hz) compression drivers in one point-source package. . .

pos
03-09-2012, 02:25 PM
This could get you more uhf on axis, but will not solve directivity and lobe issues above 7khz caused by the long adapter and the fins. You wouls certainly be better off with a normal compression driver and an external tweeter.

Mr. Widget
03-09-2012, 03:06 PM
This could get you more uhf on axis, but will not solve directivity and lobe issues above 7khz caused by the long adapter and the fins. You wouls certainly be better off with a normal compression driver and an external tweeter.Based on my experience with the 2397 and a variety of drivers, I agree completely!


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