Analysis of Klipschorn and La Scala cabinets with several drivers lists info on several drivers. But I am still a bit confused on what is considered the appropriate usable range for these drivers. I was esp concerned loking at the curves on pg 1 of that thread as K33 gets below 60-70 Hz (yet the Khorn rates down to 38 Hz) and when the K33 is above 400 Hz or so. I googled, but no luck on finding the SPL vs frequency charts for these drivers (offical or unofficial real world test).

My reason for asking: if I buy Altec 511 or 811 horns (or other horn that is only usable down to 500 or 800 Hz), can I rely on the K-33 up to 500 or 800 Hz? Khorn and/or LaScala bass bin.

I have various subs for my main room. All are 18", single or dual driver cabs.So, where to set my LFE/sub xover point, as the subs can go over 100 Hz? (B1800X 42-250 Hz, xover at 80-150 Hz, low / high pass filters at 175 Hz).

Similar issues regarding the mids (vs trachorns) and tweeters (vs Crites or Beyma).

Thx

NOLA

The high frequency limit on the K-Horn bass bin is determined by the geometry (folding) of the horn and not by the K-33 woofer. Have a look at the JAES (2000) article by Delgado & Klipsch, They show frequency response measures of the Klipschorn (relative to the Jubilee). You will note there is an appreciable dip in the response at about the crossover point you are aiming at. The article has been posted on the forum and you should be able to search for it.

The lower point of the Altec horn is not a simple number. The lower you cross it, you need to worry about the 1) choice of diaphragm material, 2) steepness of the crossover, 3) the amount of distortion if you drive it hard (loud). The 811 will not be a good choice. BTW, there are many other choices for horns besides the altecs (that are still in the same price range).

As far as the low frequency extension of the bass bin, you need to remember if the measure was made in free-field or in a corner (1/8 space). Some of the plots floating around will have different degrees of smoothing. I would not worry too much about the measured low frequency response, since this will all be changed (perhaps drastically) once you place that cabinet in your particular room.

nola:

 Analysis of Klipschorn and La Scala cabinets with several drivers lists info on several drivers. But I am still a bit confused on what is considered the appropriate usable range for these drivers. I was esp concerned loking at the curves on pg 1 of that thread as K33 gets below 60-70 Hz (yet the Khorn rates down to 38 Hz) and when the K33 is above 400 Hz or so. I googled, but no luck on finding the SPL vs frequency charts for these drivers (offical or unofficial real world test).

My reason for asking: if I buy Altec 511 or 811 horns (or other horn that is only usable down to 500 or 800 Hz), can I rely on the K-33 up to 500 or 800 Hz? Khorn and/or LaScala bass bin.

I have various subs for my main room. All are 18", single or dual driver cabs.So, where to set my LFE/sub xover point, as the subs can go over 100 Hz? (B1800X 42-250 Hz, xover at 80-150 Hz, low / high pass filters at 175 Hz).

Similar issues regarding the mids (vs trachorns) and tweeters (vs Crites or Beyma).

Thx

NOLA

I have had both Khorns (30 years) and La Scalas (about 6 months) for mains. Under the LaScala mains, I had one and two MWMs woofers with K-33's. I can honestly say that the LaScala bins, being "short horns" will go up to the 700-800 Hz. range, since there are fewer turns that the higher frequencies must make. Using the LaScalas with sub woofers of some kind is optimum for most music on Digital Media since it can contain frequenices all the way down to 4Hz, theoretically. If one is using subwoofer, then I much prefer the K-43 woofer in the LaScala. It has a much better marriage of sound with the low end of the K400/K55 than the K33 does, which is a compromise in trying to get lower bass out of a short horn (which it does, but sacrificing the higher end in doing so).

Also, while I have not had the Beyma tweeters, I have had the Crites (very good improment over the K-77 if you must match the form factor and location) and JBL 2404's which the Beyma's try clone. By far a better tweeter than all of them is the B&C DE-10 Mated to their ME-10 horn available from Parts Express. Each tweeter/horn combo is about the same size as the Beyma/JBL type, but with 2 db higher output becaude of the 90x60 degree horn lens. A pair of those brand new will be about half the price of New Beymas or used JBL's. I'm currently using a bunch of them in my Surround and they are wonderful.

Even if you cross at 800 Hz. the Altec 500 Hz. horn is still a better choice. The bigger the horn, the better the horn because you can use a 1 st order slope in the Xover without hitting bottom as quickly as you do with the same mid driver and a smaller horn..........IOW, better loading at lower mid frequencies and a better blend to the woofer section, especially if it's a K-43.