It is a subtle and undemonstrative thing that Kathryn Williams does, so it's no surprise that she has slipped the leash of a major deal and returned to releasing records through her own little label, Caw. A shame, perhaps, that there is now no fearsome engine propelling her into homes across the country, but her deceptively delicate songs were always too spiky to package. She seems happier now; certainly she's never been in better voice, bathing in the gentle, glorious natural reverb of this beautiful Wren church.

Her voice is a feline thing that pads stealthily around the songs, close to a whisper or a sigh for much of the evening. It seems appropriate that she begins with Soul to Feet, a gentle bossa-inflected ripple that advocates stillness over clamour.

Williams is the laureate of the tiny moment - of glances, breaths, little intimacies only two people can share; small things on which the world turns. A gorgeous new song, When, notes the instant when "a touch comes down on who it's meant to rest". Breath finds her lying in bed in the morning after her lover has got up, realising "it's not a waste of time to lie and feel the heat leave the sheets". Flicker condenses a human life-span into "a flicker and then a breeze"; Ivor Cutler's Beautiful Cosmos spins out a universe between cups of tea.

The pin-drop hush buoying up the fragile arrangements is such that when Williams really lets rip - a brutal, lonely almost-howl in the closing moments of a take on Leonard Cohen's Hallelujah so intuitive it makes you forget the countless other interpretations - the effect is devastating.

Wringing further beauty out of this apparent simplicity, she has the perfect foil in cellist Laura Reid. But Williams doesn't make polite music: if anything, the prettiness makes its flinty truths hit home even harder.