Karlson "projectors" and HF waveguide tubes


Paid Member
2005-08-16 4:21 pm
junk science? - or useful device? lol - -using a $12.60 Sammi 8" I think a pair of little klams could be fun for about an acre of coverage. John Karlson had the vertical "Rocket" speaker around 1959 and rotating it 90 degrees came up with asymmetric projector line of PA speakers. Jess Oliver produced some of John's designs until John's passing in 1973. This one is based on Alan Weiss's "Rocket" which derives from Karlson's 1961 Rocket. Alan likes a 40 degree wedge and some open nose area. Karlson's original klams had long aspect. Front coupler volume is usually about the same as the rear chamber volume.

I didn't have enough preamp gain to push the speaker in the video below - it would play at least 10db louder than that presentation-- my kid said at 150ft that it sounded like the drumkit was in the local church where he was standing

these are strange but interesting devices---theres some of the mechanical reverberation present - - If the 8" klam were scaled to a 12" then might not have any lower cutoff. Cutoff is very high but playing music loud kinda makes up for it.

IIRC according to some literature, the military once tested Karlson's projectors for wide coverage applications.

Radio City Music Hall had 15" driver AP100 Karlson projectors (Altec 421 + K-tube - mounted somehow)

CN looks at system Q or Qtk in this case - not sure how that would apply if LF slope approaches 3rd order.

video playing drum solo

picture of klam w. B20 - rear chamber was a bit larger than needed to accommodate psd2002 on Beta 8cx. I liked the little Sammi in this noisy toy and felf it could take more power than B20

I very much like Karlson's open ended waveguides including X!5 unit and Transylvania Power's "The Tube" - -maybe Magnetar has some comments on the tube.
Hi Freddy,
How's it going?
Got any construction measurements/diagrams for those Klams?
I'm thinking of making a pair to project ~ 10m from my garage to a pergola I just built (so I can drown out my neighbours country music :), or perhaps a bessel array....but that's too complex
(How about a bessel array made of Klams... now that would be something)
How low do the 8" Klams go?
Pete McK