Kalervo Kulmala was the principal horn of the Estonian National Symphony Orchestra from the 2010 to the 2019. Before he has been the principal horn of the Finnish Radio Symphony Orchestra from 1972 to 1983 and the principal horn of the Savonlinna Opera Festival Orchestra in Finland from 1974 to 2019. He is also professor of French Horn at the in Estonian Academy of Music and Theatre (EMTA) since 1994.

Kalervo Kulmala has been teaching for over 40 years at the Sibelius Academy of Helsinki, where he has been Head of the Brass Music Department from 1988 to 2015. Many of his students are now working in professional orchestras of the whole Europe. He established and instructed the class for Wind Orchestra Conductors at the Sibelius Academy from 2001 to 2007.

Kulmala has also worked as chief tutor of wind orchestra conducting for the Finnish Defence Forces' military conducting course both in Finland and abroad and was the chief conductor of the Kouvola and Vaasa City Orchestras. Since 1996 he has tutored the horn section of the Gustav Mahler Jugendorchester. He has been a tutor of the Simón Bolívar Orchestra in Venezuela from 2000 to 2009 and again in 2018 and has tutored the horn section of JONDE on several occasions.