Samba Em Preludio includes only two instruments as well as Spalding's voice.

• Acoustic bass guitar - This is like a bass guitar but has a hollow body which allows it to be heard without amplification. It produces a natural sound which is similar to an upright double bass but also clearly guitar-like. Spalding pushes it to its limit in the third bar (0'12) by including a harmonic on a G, sounding a little ethereal and ghostly. Many double stops are included as well, as discussed in Harmony.

• Acoustic guitar - This is a nylon string guitar, associated with the classical style. It is a little softer in tone quality compared to a steel string, which is usually used for pop and rock music. The nylon string guitar can be plucked using the fingers to create that distinctive flamenco sound heard in the solo from bar 54 (2'24). This is combined with strumming as well as a virtuosic outro from bar 112 (4'55).

Spalding uses a low tessitura in her voice which produces a distinctively mellow and relaxed sound. It lacks the intensity heard in a singer using their higher register and this suits the mood of the song well.

Dynamics aren't written on the score because the performers all play at a consistent volume. There are points which are quieter because there are fewer instruments but generally the dynamics are very constant, providing a suitably warm and smooth setting for the song.

Articulation is also very minimal. Guitar playing techniques are discussed in Melody (such as slides and pull-offs) and these are relevant to the sonority of the sound. Again, these make the overall tone quality typically flamenco, supporting the setting of the song.