Tenor Flute (Bass)
This is the largest commonly encountered flute and is pitched one octave below the C Flute. It is the same pitch range as the Viola. It has a soft and mellow sound, and is quite often haunting. Most technique from the C Flute can be transferred to the Tenor, though passages in the third octave tend to be challenging. It is best to keep this, and all lower flutes, out of their very top ranges. Some Tenors do possess a low B foot, but their availability is unknown, so it is best to avoid this note altogether.
Typically, the Tenor Flute is the lowest voice in a flute quartet (2 C Flutes, Alto, and Tenor). In larger flute ensembles, the Tenor Flute is sometimes doubled an octave lower by the Bass Flute. This doubling helps to ensure that the bass line is audible and adds considerable warmth (akin to Basses doubling Cellos in the orchestra).
A special note: from the Tenor Flute on down to the Contrabass, all low flutes benefit from amplification. A player who specializes in the low flutes will almost assuredly have a small speaker and microphone set up as part of their gear. I would greatly advise the use of amplification with all lower flutes.
Jean-Pierre Rampal playing a jazz etude on the Tenor Flute
Three Philosophies, concerto for low flutes