Original vintage Klipsch:
The Klipschorn is the big one, the design that PWK first released and that formed the Klipsch reputation. Other all-horn systems by PWK were conceived to offer Klipschorn technology in smaller or less placement-dependend packages (LaScala/Belle) or technological refinements (Jubilee). It is one of the most copied and home-built horns around. Obviously, with its long lifespan and many occasions of publication, there are bound to be many versions out there. They are all basically the same, although there seems to be a preference for older versions. The plans available online are often tied to a 1949 version of the Khorn. Due to the massive amount of plans and the apparently limited amount of differences, I list two: a full version and only the bass section.
Interestingly enough, the LaScala started out as a PA-speaker, supposedly used to fire speeches off a campaign-truck in an election. It turned out to work well inside the home as well and was taken into production by Klipsch. I list two versions. One is Klipsch authorized. It was originally in metric and published in Germany, there is also an update in inches available here. The other is a later reconstruction by a member of the Klipsch forum. Plans are here. This has been reconstructed from measurements on real life LaScala's. I think they measured dimensions that they could reach, and deduced the others.
Basically, the Belle is a LaScala in different aspect ratios. It is the same height, less deep but wider. Horn/expansionwise, it should be more or less the same. There are some differences to be found, but these are fairly minimal and uncritical. The Belle was designed as a third, center speaker, to go between two Klipsch horns. At the time it was intended to fill a sonic gap, if the two Klipschorns were placed too far apart. There was a filternetwork to go with it, which summed/detracted the left and right channels and filtered out the center channel information out of it. I don't know where that filter schematic is, it would be nice to add it here. I think it was in the Dope from Hope series. I'll look it up for you. In any case, the plans I found are recently inferred from an actual specimen, by a Klisch forums member.
The Jubilee is either an update, or a replacement to the old familiar Klipschorn, it depends a bit on your perspective. PWK started the Khorn as a 2-way, but with increasing bandwidth of source material, stretching the midrange driver more into treble territory was unfeasible and the Khorn evolved into a 3-way loudspeaker. PWK was apparently unsatisfied with this and as his final act of speakerdevelopment designed the Jubilee, together with Roy Delgado. Under Related Material below, you can find the patent of the Jubilee, explaining the design considerations and strategy, I won't go into great detail here. Suffice to say it has equal or lower bass response and a significantly higher cutoff. The Jubilee is mostly found in DIY versions, since Klipsch is not selling a consumer edition. They will deliver the PA edition to private buyers. This is a fairly rough cabinet though and not livingroom friendly. There is an inferred set of plans online, which has been traced and reconstructed from the original patent.
I covered this area in an earlier post, which you can find here.
- Klipschorn paper, which is the patent paper in which the original Klipschorn was described.
- Jubilee paper, featuring the design of the new cornerhorn, and a comparison to the old Klipschorn.
- Dope from Hope, a periodical from the Klipsch company, in which PWK himself wrote about the things he thought were essential for high fidelity reproduction. Besides solid information from respected audio-engineer, it is also an amusing read. PWK was a unconventional thinker, and writer.
You will notice many of these files come from http://www.pirkensee.de/. The maker of that website has his own Klipschorn-based system and loads and loads of horn-related literature online. Well worth checking out. Most of the other stuff comes off the Klipsch forums. I think Klipsch is great to acknowledge their rich history by keeping the heritage line alive. They are also wonderful for providing the vintage fans with this much information about their "old stuff".