When the Klipschorn was introduced in 1946, the primary input device was the phonograph. In those days the low end response of a phonograph pick-up was rolled off at 50Hz or so to avoid rumble and other issues at such “useless” low frequencies.* While this made sense in view of the typical speakers available, it left nearly an octave of bass response that a Klipschorn would have been happy to reproduce. Paul anticipated this situation long before he founded Klipsch & Associates. At least as early as 1940 he was designing his own phonograph pickups and arms. A small portion of PWK’s many drawings can be viewed here. This was during his employ in the oil exploration industry in Houston, TX. Only the X-1 woofer had been built at that time, and since it proved to be inadequate, it resulted in the development of X-3 at the proving grounds during WWII.
During his “Houston period” he corresponded with several companies trying to find a good wide-range pick-up. This included Audak Company, The Brush Development Company, and Sound Scriber Corporation. Since “high fidelity” in the home was barely in its infancy, he was communicating with companies that provided professional equipment to the broadcasting industry. Up to this time his favorite pickup was the Astatic “Featherweight”.
On 7/31/1942 Paul corresponded with Lawrence Fleming, who had authored a JASA article on pick-ups. By this time he was stationed at the South West Proving Grounds in Hope, AR. An interesting and slightly prophetic statement in this letter:
I am seeking some suitable pick-up to use in demonstrating a loud-speaker combination which I hope to complete some day, perhaps after the war.
Paul W. Klipsch
Capt., Ord. Dept.
Throughout the rest of 1942 he corresponded with many professional pickup companies including The William Miller Corp., Decca Records, John Gabel Manufacturing Company, Presto Recording Corp., Pacent Engineering Corp., Electrical Research Products, Inc. (Western Electric), Damon Transcription Laboratories, and Fairchild Aviation Corp. In almost every case, the specter of World War II put up road blocks for any non-essential commerce. In one letter Paul suggested that the development could in part support the officer’s club! Late in the year Paul placed the following want ad in Electronics magazine:
Wanted: High grade low-pressure phonograph pick-up, preferably magnetic; state make, pressure, condition, price. Will sell Jensen A-12, W.E. 555W Speakers. Paul W. Klipsch, South-western Proving Ground, Hope, Arkansas.
In any case, the trail (as discovered so far) goes cold until after the war. In a 1947 letter to Gray Research & Development, he recounts his early favorite (Astatic) and how its short-comings led him:
…to construct a variety of types, including the capacitor FM of Beers and Stinnet, a strain-gage (a series of them in fact) a-la Baldwin-Southwark wire type, and finally a magnetic which I was on the verge of attempting to patent when Bachman reported the identical structure.
The latter prototyping effort began in the spring of 1946. He secured Alnico V magnets from Thomas & Skinner Steel Products Company (Indianapolis!), coils from Vacolite Company (4000 turns of #44), and raw 1/16” brass stock from Metal Goods Corporation. The “patent model” resides in our collection.
Meanwhile, Paul met Norman Pickering at an IRE convention in February 1946. Paul was still wearing the uniform of a Major, Ordinance at that time. Mr. Pickering had already built a Klipschorn woofer from Paul’s drawings. Later Paul tried to talk Norman into one of his newly manufactured K-5-J’s to compliment the woofer. However, Norman was impressed with the Atlas HF-1, and tried to talk PWK into it!
However, the LF cut-off was too high to meet the K-horn woofer’s upper limit. Paul also suggested that Norman visit Sherman Fairchild’s NYC apartment to hear his Klipschorn. Lengthy technical discussions of Pickering pick-ups compared to others ensued. Paul’s favorite at that time was the GE, again a professional model for broadcasting.
Until the advent of tape in the consumer arena, PWK would fight the deficiencies of the phonograph pick-up. Many letters to manufacturers offered product improvement suggestions, and at least a few were implemented. In 1951 he wrote The Phonograph Pickup. It is unclear if it was ever published.
*Note the general acceptance of “wide range” as even being desirable was hotly debated until the late 1940s.