The alto horn (in E flat) has a conical bore like the orchestral (French) Horn (in F) and uses deep funnel-or cup-shaped mouthpieces depending on the model.
The alto horn (in E flat) has a predominately conical bore like the euphonium, orchestral (French) horn (in F), and flugelhorn. It uses a deep funnel-or cup-shaped mouthpiece depending on the model.