Wood Tractrix horn upgrades Do your Klipsch speakers sound harsh or give you a headache after listening for a while? It's a very common reaction and the reason is the squawker horn! This is the fix!

Wood Tractrix horns will no longer be available directly from ALK Engineering. The Trachorns have always been made by Bill Martinelli of woodhorn.com. Mr. Martinelli has moved on to other endeavors and will no longer be making them.

Dave of Fastlane Audio and I will be working together to develop new horns that we expect will be comparable. We hope to offer both a 1-inch and a 2-inch version for the Klipschorn. Here's a glimpse of the 1-inch version and mounting frame: Fastrac K
A new horn and frame will also be offered to directly replace the K500 horn in the Belle Klipsch without the use of top-section risers.

The "stock" grill frame assembly.

On the right is a grill frame from a Belle Klipsch. It's the K500 squawker horn, K55V driver and "Z-bracket" K77M tweeter. A frame out of a Klipschorn, on the left, looks the same except everything is a little bigger. It uses the K401 horn and K55M driver instead. Both frames are held to the sides by 4 long screws. The screw positions are marked by red arrows in the pictures. Remove those 4 screws and the entire thing slides out the front! They are very easy to remove and replace.

1 Inch or 2 Inch drivers ?

Should I spend the extra money for a 2 Inch throat driver and horn? They say that a 2 inch horn is supposed to be better. The truth is that this is quite true, but the difference is hard to measure at normal listening levels. Look at the intermodulation distortion plots of a 1 inch driver on a 1-inch horn versus a 2 inch driver on the 2 inch horn. The small "spikes" on the bottom line are the distortion products. This illustrates how even a high quality 1-inch driver will overload when used on a Klipschorn at moderately high levels. There is no quality 1-inch driver that will handle 400 Hz without distorting the sound. These drivers all have light metal diaphragms designed to go up high in frequency. They won't go down like the phenolic diaphragm in the stock K55 will. The only drivers that will are 2 Inch drivers! The Klipschorn squawker driver needs to handle the 450 Hz tone because the woofer won't go up that high. The Belle Klipsch and LaScala can be crossed over at 500 Hz. The 450 Hz tone would go to the woofer, so the Belle and LaScala don't have this problem to such a degree.

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The real reason to move to a 2-inch horn is to allow a better driver than the stock K55 to be used. This is why a 2-inch horn is being suggested, not to extend the lower limit of the midrange! There is simply no 1-inch driver that will do! The B&C DCM50 driver is being offered for 2-inch horns. It was designed for the 400 Hz crossover required by the Khorn.

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ALK will still be offering the B&C DCM50 2-inch driver which is an ideal driver for use in the Klipschorn. ( $760.00 ) No known 1-inch driver can replace the stock K55V without distortion. This should not imply that a K55 driver should be jury rigged to the throat of a 2-inch horn. This creates a major discontinuity in the throat no matter how it is done. Long conical extensions ruin the tractrix expansion which is itself a discontinuity.

NOTE: If you do decide to replace the K55 with a better driver you should realize that your "stock" Klipsch network will no longer be usable. All of them depend on the natural roll off of the K55 at 6000 Hz to form the crossover. Very few quality drivers do this. They usually operate far higher. This means the squawker and tweeter will both be making a sound simultaneously. Better drivers will normally be louder too. Only the networks from ALK Engineering will do.

The B&C ME10 tweeter and ME10 horn will also still be available from ALK Engineering $115.00 . Another good tweeter is the Selenium D220TI and HM17-25 horn. These are available from Bob Crites. Both of these tweeters have very low distortion even at extremely high levels.

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