St Patrick’s Cathedral, Dublin Tonight/tomorrow 7.30pm 25 01-4754817

RTÉ NSO/GAVIN MALONEY

NCH, Dublin Tues 1.05pm Adm free 01-4170000

For many a year, the RTÉ National Symphony Orchestra has spent more time playing Offenbach than Bach. Before last October’s performance of the B minor Mass, you had to go back to the 1980s and the late János Fürst’s years as principal conductor to find the orchestra playing major works by Bach within the concerts of its subscription season.

And now the B minor Mass is followed by two full nights devoted to a complete performance of Bach’s Christmas Oratorio, this time in St Patrick’s Cathedral. The soloists are Julia Doyle, Paula Murrihy, Mark Padmore and Peter Harvey, with the voices of the RTÉ Philharmonic Choir; the conductor is Matthew Halls (pictured).

The first of this year's free lunchtime Horizons concerts features Cork composer Karen Power, who has chosen to present two works of her own (the intriguingly titled One piece of chocolate per bar and no chaos: only organised panic) with Michael Alcorn's Synapseand Giacinto Scelsi's ground- breaking Quattro pezzi per orchestra(ciascuno su uno nota), pieces on a single note that are now more than half a century old. Gavin Maloney conducts.