Lehmann "Walzen" Compensating

Date of Manufacture:

The compensating double horn by Carl Lehman & Co. shown above is a fine example of a "walzen" horn. The term "walzen" (German for roller, barrel, or drum) describes the large rotary change valve in the center of the horn. In this "compensating" design the B♭ slides are located between the main valves and the change valve, with additional "compensating" slides for the F horn on the opposite side of the change valve. The change valve adds proportional supplemental tubing to the B♭ slides. One advantage of a compensating horn is its lighter weight since tubing is shared between the F and B♭ slides. In addition to Carl Lehman & Co. horns of this design were also produced by the firms August Knopf, Joesf Lidl, and other makers. This horn dates from about 1925 and the label (below) states that patents are pending in Germany and foreign countries. Carl Lehman was a brass instrument maker who flourished in Hamburg from ca. 1925 to ca. 1944. Deutsches Reich Patent 440308 for a Schaltventil für Blechblasinstrumente (Switching Valve for Brass Instruments) was issued jointly to Lehmann and Erdmann Chemnintzer on November 24, 1925 with subsequent foreign patents for the same valve design in Austria (107404, October 10, 1926), Great Britain (263460, December 30, 1926), France (622,226, February 21, 1927), and the United States (1,642,783, September 20, 1927).

31
St.L.
Carl Lehmann & Co.
Hamburg
Patent Doppelhorn
DRP
Auslandpatente ang

(Note: The initials "St. L." appear to be a later engraving in a different typeface, perhaps by a previous owner or repairer.)

With minor differences to the wrap, the body of the horn (above) closely corresponds with the original patent drawing (right). The components are identified in the list below, right.

The four-story barrel-like rotary change valve (1, 2) at the center is the subject of the patent. As shown in Abb. 4 of the drawing, it has a total of eight pairs of ports corresponding to the attached tubing segments. The air column begins with the mouthpipe entry to the main tuning slide (7) and enters the change valve at one of the top ports. Assuming that the horn sits in F, the air path continues through the change valve to the F extension (18) returning to the other port where it connects to the secondary tuning slide (17) and enters the bank of rotary valves. If the change valve lever (3) is pressed, the F extension is bypassed and the air path is directly from (7) to (17).

For the three simple rotary main playing valves, the slides for the B♭ horn lie between the valves and the change valve. For example when the thumb and first valve are pressed, the change valve is closed and the air path is through segments 9 and 12. For the F horn, when only the first valve is pressed, the air path is from segment 9 through the change valve to the F compensation segment (18) and then back through segment 12 to the first valve.