Piano Trio No. 45 refers to a specific piano trio composed by Joseph Haydn. It is one of the many piano trios within his extensive output in the genre. While Haydn composed dozens of piano trios, numbering conventions vary. Therefore, "Piano Trio No. 45" is often used as a convenient, though possibly imprecise, identifier.
Without further specifying the Hoboken number (Hob. XV:XX) or other cataloging details, identifying a specific Piano Trio No. 45 can be challenging. Identifying the key of the trio also helps, as many of Haydn's trios are commonly referenced by key. For example, a search for "Haydn Piano Trio No. 45 G major" would be more fruitful.
Haydn's piano trios typically consist of three movements, commonly in a fast-slow-fast tempo pattern. The instrumentation is standard for the genre: piano, violin, and cello. Haydn's piano trios are significant in the development of the form, often giving a more prominent role to the piano than previous chamber music of this type.
To accurately identify a particular "Piano Trio No. 45," consulting a complete thematic catalogue of Haydn's works, such as the Hoboken catalogue, is essential. This allows for disambiguation and precise identification of the work in question.