Ed. Kruspe
"Modell Gumpert Kruspe"
in F and B♭ D.R.G.M. 295125

The horn described below is  NOT part of the personal collection of Dick Martz but the description and images are shown with the kind permission of the owner, Neil Mantle.

Label :
Ed. Kruspe
Hrzgl. P.M. Hoflieferant
Compensating Double
Serial Number:
Date of Manufacture:
ca. 1910?
 F,  B♭, E, and A
4 rotary

Bell Flare:

Bell Throat:

Bell Diameter:

Base Metal:
(click on photos for larger view)

The horn shown above is an example of the Gumpert- Kruspe model compensating double horn first produced in 1906 by the firm of Ed. Kruspe. It became known as the Gumpert-Kruspe model and was probably designed by Frittz Kruspe (ca. 1862-1909), son of the founder Eduard Kruspe (1831 -1918), and Edmund Gumpert, nephew of the great horn Leipzig horn player and teacher Friederich Gumpert. This particular horn is probably a somewhat later version in that the the first and third valve slides are of the more open type than those shown in the catalog drawing  at the lower right. The label on this horn, however is of an early twentieth century style and does not include the Prussian eagle found on Kruspe horns after World War I. The shape of the F-extension tubing (above right), distinquishes the Gumpert-Kruspe from subsequent Kruspe compensating models.

The design was registered as D.R.G.M.295125 on November 19, 1906, under the title Doppelzylindermechanik für Metallblasinstrumente mit doppeltem, direkt an die Tonventile angereihtem Dreiwegstellventil nach Gebrauchsmuster 232038. [Double cylinder mechanism for brass instruments with a three-way double change valve located side by side with the valves according to registered design 232 038.1

Zeitschrift für Instrumentenbau, v. 27, nr.11, January 11, 1907, p.327

1929 Kruspe catalog, courtesy of Dirk Arzig,  

The title of the referenced D.R.G.M. 232038 (1904) is Doppelzylindermechanik für Metallblasinstrumente, mit neben und parallel zu den Zylinderdoppelventilen angeordneten, zu einem Zylinder in einem Gehäuse vereinigten Stellventilen. Double cylinder mechanism for brass instruments alongside of and parallel to the double cylinder valves in one cylinder housing as a combined control valve].2In both cases the registrations are descriptive of the change valve, but do not describe the layout of the tubing or "wrap" of the horn. The new registration is required because the valve geometry has been changed to accomodate the routing of the air path for the compensating design. The earlier valve used on the full double horn routed the air path to either the F valves plus the F extension, or to the B valves, which were independent of each other. On the compensating horn, the F valve slides are short stubs that are combined with (to "compensate") the Bvalve slides to give the full F valve slide lengths. This requires that the change valve route the air path through both sets of valve slides plus the F extension. The operative word in the registration title is Dreiwegstellventil [three-way change  valve]. The new valve, like the earlier valve, is a single two-story rotor located adjacent to the other three valve.

The text of the D.R.G.M. 295 125 submission describes in detail the connections of the new change valve to the main valve section as shown in the diagrams to the right. Note that the text does not mention the specific tonalities of the two sides of the horn nor does it use the word "compensating." Refering to the diagrams, the leadpipe is connected to the change valve (1) at port 3. From there the air path is routed either to port 7 or to port 4 depending on the state of the valve. Port 7 is connected to port 8 by way of the tuning slide at the top, and port 8 connects to port 6 with the air path routed through the upper valve slides (typically the B♭side) and out to the first branch and bell via port 10 on the third valve.

In the other case, the air path is routed from port 4 to the first valve (lower slides, typically the F stubs) through to port 9 on the third valve. Port 9 is connected back to port 5 on the change valve by way of tubing "wound according to the instrument" (typically the F-extension). Port 5 connects to port 6 as above.
One advantage of this design over the previous is stated as "...in contrast to the arrangement of utility model No. 232038 a significant simplification of the entire instrument is achieved and less tube stuff [weniger Rohrzeug] is necessary for this purpose."

Figures D.R.G.M. 295 125 courtesy of Tatehiko and Katsushi Sakaino
George Wendler (1883 – 1963) was an early proponent of the Kruspe compensating horn. He is shown at right in 1913 as a principal horn of the Boston Symphony Orchestra holding the Gumpert-Kruspe model compensating horn. Prof. Wendler came to the United States in 1909, so it might be presumed that the horn he is holding dates prior to that. He was a student of Friedrich Gumpert in Leipzig whose nephew is presumed to be a co-designer of the horn.  Prof. Wendler later married Ilse Kruspe (1898 -19??), daughter of  Fritz Kruspe.3  and in 1924 became a general partner in the company. That same year it registered his own model of compensating horn (D.R.G.M. 888990).  In 1928 he resigned as principal horn of the Boston Symphony and returned to Germany to become the head of the company a position that he held until after World War II.

George Wendler, ca. 1921
Notice that the horn Prof. Wendler holding in 1921 (above) is slightly different than the one of 1913. In particular the third valve slide is of the more open wrap.

George Wendler, ca. 1913

D.R.G.M 232038 change valve (1904)

D.R.G.M. 295125 change valve (1906)
As shown above for comparison the two change valves have different geometries to suit the routing of the air path. At left the valve found on Kruspe full double horns ("Fritz", "Horner", et. al.) described in D.R.G.M. 232038. At right the change valve found on Kruspe compensating horns ("Gumpert-Kruspe", "Wendler", et. al.).

Very special thanks to Tatehiko and Katsushi Sakaino, proprietors of  Curia Metallblasinstrumentenerzeugung and Ed. Kruspe Metallblasinstrumente for providing copies of the extant original Kruspe documents, and to Neil Mantle and his granddaughter for providing the photos of his horn. Special thanks also to Dirk Arzig, BrassTacks.De  for permission to use his images from the 1929 Ed. Kruspe catalog.


1.  D.R.G.M. stands for Deutsches Reichsgebrauchsmuster, a registration created in 1891 for the purpose of protecting for three years the design or function of an item throughout all of the German states. D.R.G.M. registered products were protected either for their way of intended use or design, but this did not include patent protection. Patent rights were secured by applying for a Deutsches Reichspatent (D.R.P.). No D.R.P. has been found for this Kruspe horn, nor have the documents filed for D.R.G.M. 295125 or 232038 been found and are presumed lost.

2. TheD.R.G.M. 232038 registration (1904) was made to distinguish a new valve from the dual tandem valves used on the first Kruspe double horn (D.R.G.M.  84240,  October 5, 1897) also known as the Gumpert-Kruspe model. That horn employed two rotary valves, one on either side of the three normal valves, and mounted perpendicular to them. This pair of change valves was connected by a rod attached to the thumb lever so that they moved together in tandem. The upper rotor selected the F or B valve slides and opened or bypassed the F-extension tubing; the lower rotor routed the air path from the selected valve slides to the first branch and bell. In the 1904 design these functions were combined into a single rotor mounted parallel to the three normal valves.

3. The New Langwill Index (1993, p.217) is in error, placing Ilse Kruspe and her brother, Walter, as children of Eduard Kruspe (1871 - 1919), son of Frederick Wilhelm Kruspe (1838 - 1911) and nephew of Eduard Kruspe (1831 - 1918?), founder of the brass workshop Ed. Kruspe.  They were in fact children of Fritz Kruspe (ca. 1864-1909), who had succeeded his father, Eduard Kruspe, as owner of the firm Ed. Kruspe. 

Waterhouse, William, The New Langwill Index of Wind Instrument Makers and Inventors, pub.Tony Bingham, London 1993

Zeitschrift für Instrumentenbau, Paul de Wit, Leipzig, selected volumes: 1907, 1909, 1915, 1919, 1924

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