Tuba

The tuba is the largest and lowest-pitched instrument in the brass family, providing the bass foundation beneath the trombones, horns, and trumpets above it. It's also the youngest standard orchestral instrument by a wide margin — not invented until the 1830s, meaning composers before the mid-1800s (including Beethoven and everyone earlier) never wrote a note for it, since it simply didn't exist yet.

Despite its size and deep register, the tuba is a genuinely agile instrument in skilled hands, and while it's typically used to anchor the brass section's harmonic foundation, it does have a modest solo and concerto repertoire showing off a more melodic, lyrical side than its reputation as a purely supportive bass instrument might suggest.

Where to start listening: the tuba's warm, exposed solo melody in the "Bydlo" movement of Mussorgsky's Pictures at an Exhibition (in Ravel's orchestration) shows its lyrical, melodic capabilities.