freddyi

hi Moray - what kind of power amps are you running? although not as sensitive, a Karlson 12 loaded with Eminence/Pyle PYM1298 (much like current Kappa 12A) & topped with the Transylvania Power Co. "The Tube" did better on drums & hi-hats than my stock FH1/K55V-511/APT150 setup. An X15 midbass could be good as would be K15 but Karlson mesh best with Karlson stuff - some horn patterns aren't a great combination. A rectangular 250Hz LE5 driven Edgarhorn was only so-so with K15 - I did like a big (30" wide) radial. A one inch format K-tube is good only to about 1K2 but 15's will reach that high. Faerber uses a very long unslotted portion on their K-coupler tweeter which protrudes thru their midhorn. I tried up to 11" unslotted portion and 5.5" slotted and that worked well with my little 15s and K18. Best, Freddy

time for an updated version of this classic

bump - -anyone here use 203 as a midhorn with a 1" driver?

fwiw the balanced version improved coherency and subjective quality on a Martin/Eminence 12" coaxial (I'd love to have a pair of 100hz cutoff Unity horns)

nice - how did the new caps sound?

anyone here run Altec 203B as a midrange with K55V? my 203B are packed way back into a shed and would have to pull out most stuff to get to them, I don't remember the adapter needed to try so would appreciate that spec. Are they worth a try vs 511? I'd run them on top of FH1

Thank you very much Dave.

which input and output taps on 3636 are used to equal the original autoformer's attenuation with 13uF and K55-V? (what is the original's squawker attenuation?)

hmmmm - have I heard something like that before? [] (the article below was part of an Australian "Mullard" book and includes the Karlson and Ed Gately Jr.'s rectangular "Super Horn") - wonder what PWK would have thought? (did he know of it?) http://gaviscon2000.fileave.com/Karlson Enclosure.pdf

here's 4 inductors marked 2.4->3mH (just got the Electra-Print so not heard it in a system) Madisound 3mH bar-core steel laminate Solen 10awg 3mH air core Klipsch 2.4mH E-core from K-horn Electra-Print 2.5mH (reads ~2.8mH on WT3) EI - core about the same size and mounting centers of the Klipsch unit dcr for the E-P came in around 0.065 ohm on a couple of runs - WT3 sometimes changes low frequency http://img64.imageshack.us/img64/1200/khorninductorcomparison.gif 100-1KHz http://img97.imageshack.us/img97/1200/khorninductorcomparison.gif 500-5Khz http://img692.imageshack.us/img692/1200/khorninductorcomparison.gif

Big thanks Bruce for the schematic and your time - that's a beautiful LS setup! Best, Freddy

I need to mate 511/K55V on top of FH1 to APT150 - what uF is good? (my measuring system is torn down)

it might not hurt to clean pots, switches, tub sockets and tighten up any physical ground connections (if any) - make sure to use a voltmeter to ensure the high voltage caps are drained before proceeding with any work underneath

I mounted a MISCO built Wild Burro Audio "BetsyK" 8" fullrange into the first Karlson Twelve (made debut October 1954) and it played very good bass at high levels for this size driver with no more than ~1/16" cone movement in each direction - in ways the bass was better than the larger speaker behind it and certainly fun - its interesting to hear that much sound for so little cone movement. There's only about 1.4 cubic foot rear chamber so some 8" will go lower than 12" in K12. The first K12 offered a movable tuning strip - a plywood bar on the rear panel to addjust the rear lowpass gap - it does mild juggling of the first two impedance peaks.

It would be fun to see a scan of your Karlson plans - there's a chance its something not seen for a long time. Karlson's little X15 at ~4.2 cubic foot external bulk was just a bit larger than the 12" enclosure so its half-space low frequency corner like the 12K was around 80Hz.. (A Peavey FH1 which was like a 6" deeper Belle had a half space low frequency corner of around 110Hz/12dB per octave.) last year I uploaded Julian Hirsch's "The Audio League" report of October 1955 where the Karlson 15 and 12 were examined objectively and subjectively http://www.audioasylum.com/forums/hug/messages/14/144523.html