Reference
OEMs & stencils
The factories behind the nameplates. A 'stencil' is one OEM-built horn sold under many retail brands — knowing which is which is the most useful transparency a buyer's guide can offer.
Many euphoniums that carry different brand names come out of the same OEM factory — a “stencil” is an OEM’s stock instrument rebadged and sold under a retail marque. This is not a scandal: a well-run stencil brand adds real value (selection and quality control, setup, a domestic warranty, service, and keen pricing). But a buyer cross-shopping several brands deserves to know when they’re comparing one horn under several nameplates.
These OEM→brand relationships are trade knowledge, rarely stated by the brands themselves, so they’re flagged for citation and hedged (“widely understood to be built by…”). They are also model-specific and change over time — a brand may source some models from one factory and others elsewhere.