David Sawer’s Rumpelstiltskin has been one of the most triumphant Sound Investment commissions in Birmingham Contemporary Music Group’s proud 25-year history.

Last week he added to the roster with the world premiere of The Lighthouse Keepers, a two-hander radio play which explores the perennially fascinating subject of people kept in claustrophobic proximity.

The original was a French play first performed well over a century ago, here enhanced by Sawer’s searchingly expressive score and some expertly convincing Sound by Design effects.

Martyn Brabbins conducted a typically adept BCMG, and Thomas Howes and William Oxborrow invested much emotional tension as the actors.

After the interval in the elegantly gracious Parabola Arts Centre it was all change for the seriously challenging radio play Words and Music by the biggies Morton Feldman and Samuel Beckett, no less. All performers were banished behind the curtain, so all we had to engage our vision were three loudspeakers conveying the delivery of actors and musicians. And wow, how it worked.

Let’s not go into the semiotics of the text, but concentrate instead on the well-dovetailed fusion of words and music, with a special nuance in punctuation both musical and verbal - and to congratulate Feldman on his hypnotic use of the interval of the seventh, a hallmark of so many composers (think of Elgar’s Enigma Variations, the finale of Rachmaninov’s scandalously under-rated Third Symphony), and here so haunting.