There are many samba instruments that are used from agogos, cuica, ganza, berimbau, and more. You can notice that traditional instruments are used when you listen to the music. Samba is a music and dance that partly defines the music culture in Brazil. The music itself consists of a quick tempo and catchy rhythm while being used for dance.
4 String Banjo - This instrument is known for being used in Samba. It sounds similar to a regular banjo but with a higher pitch. It's used as part of the rhythm section and uses unconventional rhythms when playing the Samba.
Agogo - This is a bell that is known as one of the oldest instruments used in samba. It can be a single or multiple bells which have different pitches. It is played by hitting it with sort of a drum stick in a rhythm. You can hear the agogo in the background as part of the rhythm.
Cuica - This is basically a drum that produces high pitched sounds. It is played by holding it with 2 hands. One hand uses a stick to rub behind the instrument up and down. This produces the sounds. The other hand is placed on the skin of the cuica and the pressure is what produces the different pitch.
Ganza - This is a very simple percussion instrument. You will probably notice this instrument as the one that produces a shaking sound. It is filled with beads or other items and produces the sound when you shake it.
Berimbau - It looks like a wooden bow. A string is used to play this instruments and the resulting sound is a deep vibrating string sound. It is also used in capoeira as a rhythm for the dances. It is a very driving rhythm and can be heard fairly clearly.
Pandeiro - This instrument is like a tambourine but you can tune the head to control the notes. There are many ways to play this instrument from using your thumb, fingertips, the palm of your hand as well as the sides of your hand. This is a very versatile Samba instrument.
Other instruments such as the keyboard, saxophone, drum set, acoustic guitar, tambourine, trombone, and trumpets are used in Samba. It is a genre where a wide variety of sounds are used and the focus is on the rhythm. Hopefully this has given you a good idea of this unique genre. The instruments used should give you a grasp on what are producing the rhythms and the sounds.