Here is the little I have picked up over time since I picked up my Model 4's:
The company was a wholly owned subsidiary of Schaak Electronics based in Minneapolis MN. The name is derived from name of the engineer Donald L. Kliewer. Don was an excellent engineer and had a state of then art lab for the time based on Bruel & Kjaer test equipment. The company originally made speakers under the Omega label and later developed a higher end line under the DLK label. Don did extensive testing of drivers and in the DLK line did not use off the shelf drivers but had them slightly modified to his specifications and 2nd order x-overs were used in all models. All the DLK speakers were made of ¾” mdf and had hand rubbed oiled book matched walnut veneered cabinets.
The DLK Model 1 was the first speaker in the line. It was a two way design using a Phenolic Ring tweeter and an 8” paper cone tweeter with a butyl rubber surround.
The next speakers were the Model 2 and 3. Both these were three way designs with the woofer and tweeter in phase and the midrange out of phase to smooth the x-over notch distortion, a common practice then. The Model 3 was developed first and the Model 2 was a modified 3 made to be smaller less expensive. The 3 had a 12” woofer with a foam surround in a sealed cabinet. A 4.5” paper midrange with a doped fiberglass surround in a sealed sub-cabinet. The tweeter was a Matsushita doped cloth dome with a sealed back. This tweeter was very cutting edge at the time. The model 2 cabinet had the same height and width as the 3 but was not as deep and was ported. The woofer was nearly the same as used in the Three but had a doped folded fiberglass surround and a smaller dust cap and was designed for the ported cabinet. The midrange was the same and the tweeter was the same as used in the model 1.
After the 2 and 3 were released there was a need for a model between the 1and 2 and DLK 1 ½ was developed. This was basically a Model 1 with two 8” woofers and the cabinet size increased to load both woofers. There was also a Model ½ and ¼ released later. The ½ was a sealed two way design with a 6” woofer with butyl rubber surround and a paper cone tweeter and the ¼ was a 41/2 full range driver in a small ported cabinet. The ¼ could be seen on the back deck of many cars in the seventies in the early days of car stereos.
The final speaker was the DLK Model 4 which was basically a 3 with two 12” woofers. This was known for its large size almost four feet high and it’s cultured marble top. The x-over in the model 4s were made in pairs with matched drivers and x-overs and all the capacitors were large Mylar sand filled type.
