USA made
stereo tube receivers
Bogen |
Fisher |
Harman-Kardon  |
H.H. Scott Inc Co.  |
BOGEN COMPANY from New York was associated with HK. Working in this company, Harman and Kardon met. By the way, they probably later collaborated with this company very closely, since some models of these two companies shared a common design and the power tubes used. BOGEN model names began with the letters RP followed by three numbers. BOGEN was in the segment of "cheaper" producers, unlike the next company. One of the most popular manufacturers of tube amplifiers in the second half of the 1960s was the Massachusetts company H.H SCOTT. It produced a pair of models called "Stereomaster" supplemented with a numeric or digital-letter symbol. The production of the stereo began in 1959 with the collector's model 399 with a very distinctive design and working in a "simcast" arrangement, and ended with the 345 compactron vacuum tubes, which in terms of appearance entered the 70's. Their biggest competitor in this segment was FISHER from New York. Visually, the FISHER receivers were very similar to each other. Their common feature was a symmetrical front plate, natural aluminum or bronze galvanized. FISHER has released a dozen or so models of the 400, 500, 600 and 800 series receivers that differ in terms of their end lamps and the ability to work in the MPX system. It is also worth mentioning the company SHERWOOD from Chicago, which produced specific looking amplifiers, tuners and two receivers that were a combination of them. Both symbols began with the letter "S". Another company from the "medium" segment was GROMMES, which probably offered one receiver model. Today, the well-known and then very exclusive MARANTZ did not produce receivers, but expensive kits for mounting, e.g. in walls, consisting of monoblocks and a preamplifier. Another company from the "higher" segment McINTOSH is the only company whose tube products from the 1960s are still serviced. It has released a few models of receivers that are very highly rated even today.
American-made receivers used mostly several types of power tubes. First of all, they were EL84 pentodes and their American counterparts, i.e. 7189 and 6BQ5. The typical American 7591 lamp and its Novar counterpart 7868 dominated the segment of more powerful devices. The 7591 lamp was developed as a successor to the lamp, which is little known in Europe, with the symbol 7355. This, in turn, was a development version of the 6L6 lamp. Both the 7591 and 7355 were characterized by the fact that they were short and it allowed to put them in not very tall equipment. They also had high power comparable to the 6L6GT. The EL84 and 7591 were used by all manufacturers, but only HK and BOGEN also offered 7355 equipment. These two companies also offered receivers with 7408 output tubes, which were "more powerful" versions of the 6V6 pentode. American manufacturers of receivers rarely used ECLxx double tubes, often in custom designs for other companies.