Bitten by the organ bug in the class of Chris Dubois at the Bruges Conservatory, Bart studied at the Lemmens Institute in Leuven with his great inspiration prof. Luc Ponet. In his class he learned not only to focus on organ playing per se, but also to have an eye for a broadly oriented aesthetic. He learned to expand his musical spectrum and to marvel at the exceptionally profound power of Art and Beauty.

In Paris he obtained his Prix d'excellence organ with the highest distinction and congratulations from the jury, specializing in French symphonic organ music. In May 2007 he graduated for harpsichord with Kris Verhelst and in September 2008 he obtained his Master's degree in symphonic orchestra conducting with flying colors in the class of Edmond Saveniers. He followed masterclasses with Ben van Oosten, Ludger Lohmann, Louis Robillard, Leo Van Doeselaar, Menno Van Delft, Trevor Pinnock, Skip Sempé, Kazushi Ono, Bernard Haitink, Roland Börge, among others. 

Bart's musical activities are in many different areas. He is a much sought-after and highly valued continuo player, he is often asked as a soloist or in chamber music ensembles and in recent years he has also increasingly performed as a conductor at home and abroad. His repertoire is very diverse and ranges from early polyphony to creations of contemporary compositions. He is invited by leading musicians and renowned ensembles and orchestras such as the Netherlands Bach Society, the Ensemble Il Gardellino (Marcel Ponseele and Jan De Winne), B'Rock, Flemish Opera, the Ensemble Explorations, Zefiro Torna, the Collegium Vocale Gent, the Flemish Radio Choir and Orchestra, the Tulipa Consort, Il Fondamento, Les Muffatti, Currende, the Choir and Orchestra of the Royal La Monnaie Theatre, the Ensemble Philidor, the Symphonic Orchestra and Choir of Curitiba (Brazil) and the Cluj Symphony Orchestra (Romania). Since 1999, Bart has been the titular organist of the Saint-Gilles Church in Bruges, where he plays the famous Bach organ and a unique, beautifully preserved Hooghuys organ. His pedagogical activities mainly take place at the renowned Royal Brussels Conservatory where he is the principal subject teacher of a flourishing harpsichord class. Since 2019 he has been head of the department of Early Music.

Bart increasingly focuses on solo keyboard playing (organ and harpsichord) and conducting. On the one hand, this results in a large number of organ and harpsichord recitals throughout Europe, America and Japan. On the other hand, he is regularly asked to conduct as a (guest) conductor by various (inter)national choirs and orchestras. In September 2014, he was selected from 400 candidates to conduct the final week of an international conducting competition/masterclass in Cluj (Romania), where he also won first prize. In 2015, he made his international debut as a symphonic conductor with concerts in North and South America. In the fall of 2015, he was assistant conductor to Kenneth Montgomery at the Orchestra of the 18th Century. In September 2016, he was selected as a finalist for the International Conducting Competition in Bucharest. In October 2019 he made his debut as a conductor at Opera Ballet Vlaanderen, where he led B'Rock in the production Mea Culpa by Sidi Larbi Cherkaoui. The 2019-2020 season will feature Handel's Messiah, the Weihnachtsoratorio, the St. John and St. Matthew Passions and the Magnificat by Bach, symphonies by Boccherini, Purcell's Dido & Aeneas, Mozart's Le Nozze di Figaro and Requiem, Brahms' Requiem, Mendelssohn's Paulus and Monteverdi's Vespers.

Very recently, his musical career was rewarded by VRT Klara with the Klara award for 'Musician of the Year'. The jury praised his activities with a glowing report: "Bart Naessens is the musical jack-of-all-trades par excellence. His range of action in the world of classical music is overwhelming: as a conductor and artistic director, as a player of harpsichord and organ, as a pedagogue at the Brussels conservatory and as an inspiration to amateur musicians."

In addition to the many invitations, he wants to give his own insights and passions a personal interpretation. That is why he founded the ensemble Capriola di Gioia in 2007 together with his wife Amaryllis Dieltiens, where they focus on the performance practice of the baroque repertoire in an original and affected way. In 2010 a long dream was realized with the foundation of the ensemble BachPlus. With this he wants to create a platform for the performance of the (cantata) repertoire of JS Bach and his contemporaries. This project is currently reaping special success at home and abroad, the ensemble charms many music lovers with their professional, original and particularly enthusiastic performances.