As any good choral singer knows, you can’t deliver too emphatic a “k” for the opening Kyrie Eleison of any one of thousands of Mass settings. Well, almost. The Scottish Chamber Orchestra Chorus produced such a distinct, detached, and powerful opening consonant for this performance of Bach’s B minor Mass that it seemed to bounce several times round the auditorium before being enveloped by the great tide of chromaticism that characterises this magisterial movement.

Bach: Goldberg Variations Víkingur Ólafsson (piano) (DG)

Bach Goldberg Variations Reimagined Rachel Podger/Brecon Baroque (Channel Classics)

The Edinburgh International Festival’s focus on Korea moves to the Queen’s Hall in the festival’s middle week, with performances from two Korean soloists playing alone.

There’s a Korean strain to the Edinburgh International Festival’s programme this year, more in the drama programme than in the music one, but it came to the Usher Hall in Friday night’s concert from the KBS Symphony Orchestra (★★★★). They play a similar role in Korea to what the BBC Orchestras do in the UK (KBS stands for Korean Broadcasting System) and if this concert is anything to go by then they’re a jolly impressive bunch of musicians.

Otto Klemperer: The Warner Classics Remastered Edition (Warner Classics)

Founded two decades ago by Franco Buitoni and his wife Ilaria in league with their good friend Mitsuko Uchida, the Borletti-Buitoni Trust never seems to put a foot wrong in its choices: the present and future are as dazzling as the last 20 years. As well as giving generous long-term support to over 200 artists and groups, BBT commissions new works – more than 50 to date – and has set up a Communities wing "to encourage social cohesion".

Brahms: The Four Symphonies, Piano Quartet No. 1 (orch. Schoenberg) Luzerner Sinfonieorchester/Michael Sanderling (Warner Classics)

The turbulence and agitation of betrayal could be felt from the word go in this galvanising performance of the St John Passion, which administered a jolting urgency to Bach’s radical portrayal of the Easter story. The work will be 300 years old next year, yet this Polyphony Good Friday performance – a fixture at St John’s Smith Square for slightly fewer years – delivered a version as fresh and discomfiting as if the crucifixion had taken place yesterday.

Tenebrae in tenebris: put more plainly, a top choir that’s anything but shadowy, except when it needs to be, doing its bit for the darkness of Maundy Thursday. The thoughtful plaiting of Bach motets with three Tenebrae Responsories and other works by our top choral composer, James MacMillan, worked well until the last work on the programme. Then they had to go and spoil it all by premature ejaculation.

In Márta’s Garden Katharina Weber (piano) (Intakt)