Whether it is broached in music, literature, painting or theatre, the subject of slavery remains a pivotal undertaking for African-American artists, all the more so given the slide of the country towards depressingly open bigotry during the Trump regime. Producer-installation artist Yvette Janine Jackson's Freedom is a potent meditation on what remains a defining event in world history precisely because the work can't be pinned down to any single form.

She herself calls her creations ‘radio operas' and they do indeed have the compellingly fraught charge of a story in sound that seeps across the airwaves. Conceived in three acts ‘Destination Freedom' vividly evokes the Middle Passage through carefully distorting textures that convey the elemental imagery of wind and water, industrial materials, such as the rhythmic scrape and clink of metal and steel, as well as human breath with its spectrum of graceful dignity and violent desperation. Echo, reverb and delay take centre stage alongside note and tone.

Think of a whirlpool slowed down, boxed up and buried deep, in line with the epic trauma of the slave experience. Jackson's production and mix bring out great nuance to induce affecting emotional movement amid the dehumanised spectral stillness, and at its peak the composition has the gravitas of a George Lewis electronic tapestry.

Equally compelling is ‘Invisible People', which calls out stark prejudice against LGBT identity within African-American communities. Gurgling reeds and creaking strings enhance soundscapes that also feature spoken word, be it biblical-derived homophobia or mangled automated voices. Jackson is thus conducting an essential investigation in Freedom: she is looking at oppression with its far-reaching historical roots and shifting modern day manifestations in a unique audio drama that is as austere as the subject matter requires, yet unrestrained in its inventive energy.