There is no specific information about the music being played on the panels of the Ghent Altarpiece. It might be music that we cannot know: the song of the angels, heavenly sounds, mystical music. Two of the panels painted by the Van Eyck brothers show both angelic and human figures. On the left-hand panel, between Adam and Mary, singers are standing around a lectern that holds a manuscript. On the right-hand panel, between Eve and John the Baptist, someone is playing a small organ. Two others, with a harp and vielle, are watching.

Singing and music-making angels transcend tangible, everyday musical practice. The hosts of heaven sing and play music that is inaudible to human ears, something more beautiful than the music that can be made on earth. This is divine music that humans simply cannot imagine. But because the angels are also portrayed in a very human way, they contribute to bridging the distance between the unknowable liturgy of heaven and the liturgy that we hear here on earth.

At the time when the Altarpiece was painted, the vocal music of the Christian Church had made an enormous shift towards polyphony. Gregorian formed the basis of everyday liturgy, but for festivals and special occasions, no polyphony was too rich or complex. Fifteenth-century singers, including those specialized in polyphony, were thoroughly versed in Latin and the Gregorian liturgy. When the Van Eyck brothers painted angels, they were surely singers like these: they sing both Gregorian and polyphony. The singers were also very familiar with secular song repertoire.

The Mystic Music exhibition explores the musical world of these famous panels. Are the angels singing Gregorian or polyphony? Is the organist on the right accompanying the song we can see being sung on the left? Will the harp and vielle play a chanson later on?

How do we approach the music of the fifteenth century today? Is the organist accompanying the singers, and are the angels with the harp and vielle about to join in? How do musical performances more than five hundred years ago still inspire musicians today? And what can an instrument maker do to understand the art of organ playing in the Late Middle Ages better?

Sonorous answers to questions like these were sought in the work of the instrument maker Andrzej Perz (Ghent University College) and that of Hendrik Vanden Abeele (Psallentes).

Two instruments from the Alamire Foundation collection (a vielle and organetto) were also loaned to the exhibition.