MADAMES Lennox and Mitchell have had very different musical careers, but share a penchant for the protest song.

Lennox has long been a peace and HIV-awareness campaigner and these two issues inform the 11 new tracks on her fourth solo album.

Lennox earns credit for giving pop equal billing with her politics. At 52, she may be older and wiser, but she hasn't lost the knack of writing a great hook and a memorable melody.

Her voice too has never sounded better, ranging from the fragile ice queen to the tortured temptress.

Highlights include the gospel stomp of Ghost In My Machine and the emotional riptide of Big Sky, where her voice is as deep and cavernous as the darkest pit of a broken heart.

In the past Mitchell sang about bombers in the sky and paving paradise, but her main preoccupation was love. ("There's a wide, wide world of noble causes and lovely landscapes to discover, but all I really wanna do right now is find another lover.").

The 63-year-old has come out of retirement, and a bitterly-announced one at that, for Shine, where her twin focus is on the war on terror and our environmental plight.

Although it is all very worthy, it does seem one dimensional, except on the reworking of Big Yellow Taxi, where the lyric and simple backing track remind us of how Mitchell once could say so much more with so much less.

It's worth noting that the best pieces are the opener and closer - the instrumental One Week Last Summer, a jazzy melange of sax and piano with the eccentric pacing and melody which Mitchell made her hallmark, and her poignant reworking of Kipling's If.