JBL 2235H for Klipschorns

[Khorn]

Anybody here tried using the JBL 2245H med eff low frequency driver in Klipschorns? I would guess a multi amp configuration would be needed for driving it due to the less compliant driver as well as the lower sensitivity rating, although it is capable of handling a steady sine wave input of 150 watts so could be driven by a huge amp. If so what frequency dividing network did you use and what alteration was necessary for the driver throw (22mm peak to peak excursion)?

[Frzninvt]

Unless its T/S parameters are similar or identical to the K-33E's it won't sound right. Worth a try I suppose, why not. That is a beefy woofer I think that was the woofer I had in my JBL B-380 subwoofer if I am not mistaken. It's bigger brother would be the 2245H 18" woofer if so.

[Khorn]

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On 6/23/2004 10:15:07 AM Frzninvt wrote:

It's bigger brother would be the 2245H 18" woofer if so.

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That's right, the 2245H is probably my fave and mounted in a 12ft/3 enclosure it can be awesome if driven by 500 to 1KW of amplification. Size constraints limit setting up a system with bass units like those in a home environment.

The smaller 2235H would be an interesting experiment iF setting up a multi amped actively X'overed Klipschorn system.

[Q-Man]

The best bet is to stick with the K-33E. It is made for Klipsch, and Eminence (sp?)won't sell it to anyone elce. They even say that none of their other drivers will work in it's place.

We talk about mods and improving the upper end of the Klipschorn, which can be done, but you never hear us telling anyone how to improve the bass horn. The genius of Paul lies in the bass horn.

[D-MAN]

Khorn,

Haven't done anything but thought about it...

There is a JBL 15" 4 Ohm version that is pretty darn close to a K33E, or so it would seem. They are much more expensive than the Klipsch driver, which is why I hesitate.

The major impact that changing out the woofer will be the crossover and the attendant mid/upper frequency outputs. They are inseparably inter-related. This problem can be better solved with an electronic 2 or 3 way crossover vs. a fixed passive one.

Here's the rundown on the Khorn itself...

1) Any 15" driver will do; the horn and back chamber are "balanced" to present an equal compression to the cone.

2) the back chamber is about 4800-5000 sq in. or roughly 3 cubic feet. The K33E t/s spec is 13 cubic feet if I remember correctly. Therefore: no correllation!

The only limits to this would be:

A) the Fc of the driver (K33E = 34.5 Hz)

the crossover point(s) effected

C) power handling

D) sensitivity (K33E = 96.5 db)

Remember that variations in sensitivity will cause a mismatch in the output of the bass horn to the mid/tweeter output, resulting in either too much or too little, and will serve to destroy the "balance". This is an expensive thing to fix. I know of where I am speaking here...

DM

[Khorn]

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On 6/23/2004 10:42:03 AM Q-Man wrote:

The best bet is to stick with the K-33E. It is made for Klipsch, and Eminence (sp?)won't sell it to anyone elce. They even say that none of their other drivers will work in it's place.

We talk about mods and improving the upper end of the Klipschorn, which can be done, but you never hear us telling anyone how to improve the bass horn. The genius of Paul lies in the bass horn.

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Agreed, the biggest attribute of the K-33 are compliance and through its loading has the ability to translate quick transients and maintain musicality to a reasonably low frequency response. Modern, specially, home theater requirements, alter the playing field to a great degree. Reproducing artillery shell explosions, volacnic eruptions and earthquakes was never an intended function of Klipschorns although they do a credible job in that regard.....to a degree.

If going the bass augmentation route probably the best bet would be to set up 2245H's in 12 cu ft enclosers driven by KW monoblocks to use with my Kipschorns then, run for my life, 'cause from that point on I'd (probably) be homeless

[D-MAN]

I forgot to mention one IMPORTANT thing:

the throat cavity opening.

This is 13 x 3 in most Khorns. It should be widened to 13 x 6 for most 8 Ohm drivers. This came from Bruce Edgar and I have proved it myself; it's true, but I can't say why.

This little mod is the main reason why most choose to stay with the stock K33E which works as well as anything, although granted other drivers can produce more powerful bass.

I have experimented, I have a 13x6 throat, I use the motor board with a 13x3 opening, and STILL chose the K33E as the best sounding to me. It has a "transparent" quality to it that can't be found in other drivers.

DM

[Khorn]

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On 6/23/2004 11:05:00 AM D-MAN wrote:

Khorn,

Haven't done anything but thought about it...

There is a JBL 15" 4 Ohm version that is pretty darn close to a K33E, or so it would seem. They are much more expensive than the Klipsch driver, which is why I hesitate.

The major impact that changing out the woofer will be the crossover and the attendant mid/upper frequency outputs. They are inseparably inter-related. This problem can be better solved with an electronic 2 or 3 way crossover vs. a fixed passive one.

I think rather than screwing around with the Klipschorn bass driver the optimal tact would be augmentation of the LF by adding the following:

for the X-over:

Bryston 10B X-Over

For the LF drivers:

JBL 2245H

Two JBL single driver "subwoofer" cabinets

For amplification at a reasonable price:

Bryston 14B

One decision would be at which fequency to X-over to the Klipschorn's bass driver.

Klipschorns coupled with a pair of these subs should be a formidable system.

[Frzninvt]

I use two Velodyne F-1500R's w/15" drivers to augment the bass, trust me the enclosure for them is much, much smaller they can dig much deeper (were talking Hz in the teens here) than the 2235H or 2245H for that matter since you will be dominant in the 30-50Hz range with those drivers and the Servo's in the Velo's make them much cleaner and accurate with no boominess whatsoever all that in a 20" cube is certainly hard to beat. Especially since they can be purchased on the used market for about $500.

I had the JBL B380/BX-63A combo with the 2235H woofer in it powered off a DBX BX-3MkII in 3-channel mode running 400W-600W and can tell you without a doubt the Velodyne provides more extended and cleaner sounding bass response than the big mother JBL ever could. Just a thought.

[Khorn]

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On 6/23/2004 2:39:28 PM Frzninvt wrote:

I use two Velodyne F-1500R's w/15" drivers to augment the bass, trust me the enclosure for them is much, much smaller they can dig much deeper (were talking Hz in the teens here) than the 2235H or 2245H for that matter since you will be dominant in the 30-50Hz range with those drivers and the Servo's in the Velo's make them much cleaner and accurate with no boominess whatsoever all that in a 20" cube is certainly hard to beat. Especially since they can be purchased on the used market for about $500.

I guess that makes a hell of a lot more sense in a home environment and amplification is included. What frequency do you X-over at?

[Frzninvt]

The NAD T163 A/V Preamp allows me to select a variety of frequencies, I usually cross them at either 60Hz or 80Hz depending on the source material.

[Q-Man]

With klipschorns I wouldn't crossocer above 50 Hz. Klipschorns have very strong output at 50Hz. I crossover mine at 40Hz. It's guite easy to figure out

where to set your crossover point by just turning off the sub to see what your missing and then turn off the speaker and just listen to what the sub is doing. Just work with the crossover point, gain or volume control and the phase control.

I have mine blending in fairly well. You never would think that the sub was even on.

You can't make the bass horn play lower by changing the woofer. The horn itself is controling the low freguency cut off point. Look at the LaScala compared to the klipschorn, they use the same woofer. You need a good sub, and there arn't many that can keep up with a Klipschorn. Room size will aslo be a factor.

[D-MAN]

Q-man is right, they won't go any lower. For the most part.

PWK published a paper in the 40's that talked about bass below the Fc of a horn. It's there, but it rolls off faster than other types of speakers.

They can be made to have louder bass (i.e., more than "normal") by swapping out the woofers. Also they can suck up more power (if that is what you want) depending on the woofer chosen.

My main concern for experimenting is to come up with an economical alternative to the Klipsch K33E, which is quite overpriced IMO for what it actually is...sheesh, the things only weigh a couple of pounds! Where's the magnet?!

But I haven't found anything that has the same sound...

DM

[Khorn]

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On 6/24/2004 10:44:42 AM Q-Man wrote

You can't make the bass horn play lower by changing the woofer. The horn itself is controling the low freguency cut off point. Look at the LaScala compared to the klipschorn, they use the same woofer. You need a good sub, and there arn't many that can keep up with a Klipschorn. Room size will aslo be a factor.

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I agree that for lower response bass augmentation in the form of subwoofers is the answer. I had LaScala's prior to Klipschorns and IMO there is no contest. It's not that the bass respose is just lower on the Klipschorns but there is a very noticable over all smoothness to the presentation over the LaScalas. The problem with finding a good subwoofer system is not so much the lower response and output but rather the "musicality". That is the attribute that the Klipschorn's possess over other speakers specially in the bass area.

Low frequency reproduction is not that hard to obtain, look at all the cheap subs around that can reproduce explosions and all that. If a sub is just meant for movie use its not hard to get at a reasonable cost. It's when you want to reproduce accurate, musical and emotionally involving bass that it becomes a challenge and, it doesn't come cheap cause the amplification also becomes an important factor. That's why the Klipschorn's folded horn system is so unique over the range that it does cover.