Pronunciation: [bˈe͡ɪs tjˈuːbə] (IPA) 
The correct spelling of the low-pitched brass instrument is bass tuba (beɪs ˈtuːbə). The spelling "base" tuba is often seen, but "bass" refers to the low frequency of the instrument, not its position. In IPA phonetic transcription, "bass" is spelled /beɪs/, indicating the long "a" sound. "Tuba" is spelled /ˈtuːbə/, with a short "u" sound followed by a schwa. So, it's "bass" as in low frequency, not "base."
The bass tuba is a brass musical instrument belonging to the tuba family, known for its deep and resonant tones. It is the largest and lowest-pitched instrument within the tuba family, typically tuned in the key of BBb (B-flat). The term "bass" refers to its ability to produce low frequencies, while "tuba" originates from the Latin word for trumpet, highlighting its brass construction and similar playing technique.
The bass tuba is characterized by its large and curved shape, consisting of a wide bell, long tubing, and various valve mechanisms which allow for different pitch productions. With its conical bore design, the instrument produces rich, warm, and sonorous sounds, capable of sustaining deep and low notes, hence often supporting the foundation of many musical compositions.
This tuba variant, commonly found in orchestras, bands, and brass ensembles, is played by skilled musicians using a mouthpiece that requires ample breath support due to the instrument's size and capability to produce forceful sounds. The player uses their embouchure to control the airflow and create different pitches by pressing different combinations of the valve levers.
Due to its size and weight, the bass tuba is usually positioned on the lap of the player, rested on a cushion-supporting device, or supported by a shoulder harness during performances. It has become a vital component of many musical genres, such as classical, jazz, and military music, adding depth, richness, and power to musical compositions.
The word "bass tuba" is a combination of two separate terms: "bass" and "tuba".
The term "bass" (or its original form "basse") comes from the Old French word "basse" meaning "low". It has its roots in the Latin word "bassus" which also means "low".
The word "tuba" has Latin origins as well. It is derived from the Latin word "tuba" which referred to a large, straight, and curved instrument used in ancient Roman military bands.
The two terms were combined to describe a low-pitched brass instrument that belongs to the tuba family. The "bass tuba" is a larger variant of the tuba with a lower range.
