Marmosets are highly vocal. 
Calling is a striking aspect of common marmoset behavior 
Marmosets make a range of high-pitched calls, some of which sound like those of birds. 
Vocalization is a very important mode of communication in marmosets because their natural environment (often dense vegetation) makes visual communication difficult.

Contact call (contact calls help marmosets to keep track of where other group members are, keeping the group together in their natural habitat where dense foliage can make seeing each other difficult) 

Made in friendly/affiliative contexts. When near, or anticipating a favorite food.

Territorial call; can also indicate a level of alertness or agitation.

Contact call
Chatter, Angry Chatter/Cackel
Body vibrates noticeably while making this call. Aggressive call; often given when eating and approached by another or when chasing.

Loud Shrill
Long distance call. Aggressive or territorial call.
An isolation call (a very long distance contact call) when made by isolated marmosets or those that have been separated.
Indicates mild anxiety.
Situations of mild anxiety.

Made when alarmed. Also heard during aggressive encounters.
Rapid fire Tsik, Mobbing call
Very loud call Given in response to the presence of a potential predator. Contagious call, all other group members typically joining in. 

Seep-Warning Alarm Call
An alarm call Given at the sudden appearance of a threat.
Squeal, Scream Adult
Submissive/distress call Given by submissive individuals, by individual ‘losing’ an aggressive encounter. Also made if fearful when being held. Vital to check the situation if this call is heard.

Infant Cry Call
Only heard from infants. To get attention from parent or group members; heard when encouraged off a carriers back. Not comfortable being alone.