D. Ansingh & Co.

The exact taxonomic classification of this unusual instrument remains a fascinating mystery, bridging the design lines of several distinct brass profiles. In terms of overall layout, it behaves and looks like a hybrid—potentially an Alto Flugelhorn, an 'Althorn in Trompetenform' (alto horn in trumpet form), or a Solo Alto Horn. Visually, its chassis bears an uncanny resemblance to a historic Althorn in Trompetenform crafted by Edmund Paulus of Markneukirchen, save for this instrument's significantly larger, more dramatic bell flare. Concurrently, comparative archives in the Horn-u-copia catalog reveal striking structural similarities to a vintage Bass Trumpet manufactured by Moritz of Berlin.

Acoustically, the horn is configured in E♭ (or approximately within that spectrum, heavily dependent on the chosen mouthpiece setup). Uniquely, the mouthpiece receiver is exceptionally wide, engineered to accept a modern large-shank trombone or euphonium mouthpiece rather than a standard alto horn shank.

The bell is faintly but unmistakably engraved with the dealer mark 'D. Ansingh & Co. Zwolle'. Founded in 1875, this prominent Dutch music house did not actually manufacture brasses; they imported 'stencil' instruments from prolific Bohemian workshops and engraved their own storefront name upon them for domestic sale. Consequently, the identity of the true artisan behind this hybrid remains anonymous.

Regarding its preservation, this horn represents a recent heartbreak: shortly after a video demonstration was recorded, the first valve deteriorated from bad to worse, rendering the instrument completely unplayable for the time being.