Best JBL mod for Klipschorn?

[Maron Horonzakz]

If the Be is manufactured properly You dont have to butter up the surface to smooth out the spikes. the 435Be could have been better flat out to 20k easily. And that ineficient 045Be what were they thinking? And they had to butter that one too. There was a better tweeter (Be) with out slathering aquacrap on it. Sidney Harmon is asleep He could have probably bought the other speaker co. And the drivers could have come out of that superior manufacturing process.

[Mr. Widget]

...the 435Be could have been better flat out to 20k easily. And that ineficient 045Be what were they thinking?

OK, I see where you are going with this.

I am not sure that the 435Be could have been made to go "flat out to 20k" since neither of the two TAD units I have (4001 and 4003) "go flat out to 20k" and they both have significantly more powerful magnets and no aqua-butter. They do have greater HF extension than the 435Be, but I believe that the "lack" of HF extension for the 435Be and lower sensitivity of the 045Be are due to engineering compromises that were accepted since these drivers were purpose built for a specific system and were not compromises within the scope of that system. These drivers were not built to be stand alone drivers but rather to enable JBL to assemble a truly spectacular system called the K2-S9800.

As to why the aqua-butter? Hell I don't know. I guess they feel it helps. They are using aluminum in the 435AL in their down market design. It would be interesting to compare the response and sound quality of the two diaphragms.

Widget

[Mr. Widget]

Sidney Harmon is asleep He could have probably bought the other speaker co. And the drivers could have come out of that superior manufacturing process.

Maybe. The retail price of the K2-S9800 is already beyond most people's threshold of pain. I assume you are referring to TAD. The cost of producing the TAD compression drivers is so high that using them in the JBL flagship would probably double it's price. I am not sure that it would be that much better.

Widget

[Maron Horonzakz]

And on that comment...B N Locanthi is smiling down on you.

[whgeiger]

XVT,

The Klipsch corner horn bass section exhibits irregular response above say, 300 Hz. [1]
For best performance, a muscular compression driver such as the JBL 2490H [2] will get the job done at the needed lower crossover frequency. To do this a reentrant mid range horn would have to be designed and built. A similar approach was used by Roy R. Carlson in his design of the EV Patrician IV [3]. Here a pair of 828HF Drivers with A8419 Horn segments radiated into the back of a wooden mid-range horn to cover frequencies between 200 and 600 Hz. The JBL driver recommended will allow an upper c/o of 1000 Hz or better if needed. Just keep horn fold width less than ½ wavelength on the highest frequency to be passed.

Regards,

WHG

[1] Title: A Revised Low-Frequency Horn of Small Dimensions
Publication: AES-J, Vol. 48, No. 10, Pg. 922 (Oct-2000)
Author: Roy Delgado, Jr.
Author: Paul W. Klipsch
Abstract: A widely used commercial loudspeaker system, originally described in 1941, has been modified and improved. The modern version of this system claims smoother response in the pass band region, reduced distortion, and an increase in its upper frequency limit. These and other improvements have been installed in a cabinet, which occupies the same footprint as that of the original design.

[2] JBL 2490H Mid-Range Compression Driver
http://www.jblpro.com/pages/pub/components/2490.pdf

Note that this driver’s flat PWT (power) response below 500 Hz becomes displacement limited at its lower frequency limit. For at home listening, this should not present a problem so long as reasonable horn loading is maintained an octave below the lower crossover frequency used. Also a high pass filter slope of no less than 24 db/octave will provide additional protection for the driver. If an electronic crossover is used, be sure to insert a large D.C. blocking and small bypass capacitors in series with the driver voice coil.

[3] Electro Voice Patrician IV and Component Drivers http://www.hifilit.com/hifilit/Electro-Voice/117-17.jpg

[Maron Horonzakz]

The AES paper on the new bass horn (Delgato/Klipsch) Is the still born Jubilee two way Klipsch Horn good up to 800hz. And the bottom end is 6db better at 35hz. A pro cinema version is in the works.

[whgeiger]

MH,

This stage system has been around for about two years.

http://www.klipsch.com/product/product.aspx?cid=502

Regards,

WHG

[Maron Horonzakz]

Yes the KPT uses 2 12" woofers.... Another version is being talked about using 2 15" woofers.

[JBLGUY]

The stock klipsch Mid horn and driver and possibly the crossover are a very nasty combo indeed. We have side by side compared these to several other combo's and the klipsch always sounds very bad when compared. My buddy doesn't even listen to his since he got his new setup. Now the K horns are sitttng upstair unused. I never did like them much. I have heard many other horns that work much better the Klipsch driver.


Speaking of Vitavox, I have a pair of the corner cabinets. I don't have any Vitavox drivers though. I am using Beyma woofer in them and have had Altec 416b's in them as well. They are a much better cab than the K horn cab. Mine have full sides ( waveguides ) on them so corner placement is less critical.

I live in the city where Vitavox Canada was located. We recently met the original draftman who drew up the Vitavox Cabinets. He was quite surprised to see a pair so many years later. We actualy have his blue print in full scale and they are huge drawing to say the least

chow

[Jim DiFalco]

Vitavox components:

http://cgi.ebay.com/ws/eBayISAPI.dll...740245019&rd=1

[Ron K]

HiAll. I have built many corner horn systems. My favorite ones always had a midbass horn with K110 or E110 or 2123 driver. I have tried most of the 1" Jbl and Altec horns on these systems. Sometimes with tweeters. Lot of fun and some incredible results. My current favorite is my rear loading corner horns with 2226 drivers. Good performance to 25 Hz, And allows time alignment with mid and high. Just my .025 Ron

[Earl K]

Okay, I'll try to keep this relevant to JBL models' ( Current & from the Past )

- Here's a possible mod. that might allow a K-Horn to run 2way and still use a crossover point down at 300 hz .

- The parts used were RCA MI-9594 Horn (with MI-9191 entry Throat) & a B&C 900 nd driver ( 3" Ti diaphragm, 1.5" exit ). This horn has a 60°x40° pattern ( it's obviously a radial design horn ).

- You can see that this horn easily loads to 300hz ( my electronic crossover was set to @ 290 hz ). This driver ( like most modern "fast-exit" drivers ) has a "highish" recommended Xover point (of no lower than 800 hz) . ( Oh Well :dont-know )

- Hopefully JBLs' new 2431h driver would holdup just as well ,when working in this lower octave ( on a huge horn ) / ( just for HiFi use ) . See Zilch for his developing 2431h information .

- A comparable horn to this RCA9594 is JBLs' old 2356 ( The one Widget mentioned ) .

[Earl K]

A Few More Pics

- these pink-noise FR displays show the effects when the CD horn boost is engaged .

- I've only listened to this setup with pink-noise. But I somewhat feel that I would forego the CD horn boost.

- I may listen to this sometime to gauge the midrange loading effects on this poor diaphragm, which is ( just about ) completely relying on horn loading for the response seen below the recommended crossover point (800hz) .

- It's hard to see, but the 6 db down point was at around 300 hz , just like it should be with this LR type ( 24db/octave crossover ) .

- Moving the crossover point lower revealed that - well - that was it,,, this diaphragm could do very little more . This diaphragm is also enclosed in a "tight" backshell ( small volume ) - just like JBLs' newer pro series compression drivers