I have no idea what these songs are about. Well – that's not strictly true - the Japanese lyrics also appear in English inside the incredibly beautiful, palest oyster-grey packaging of the album. But as Jarvis Cocker memorably pointed out, only a philistine would follow the words while the songs were playing, so for the first few listens I just sit quietly and puzzle at this fragile music, eventually puzzling less and surrendering more and more to the singular sense of melancholy it generates. Odd, in some ways, that music so sparse – acoustic guitar, occasional organ lines that sound like Gary Brooker moonlighting in Stereolab, a delicate, not-obviously emotive female vocal – can communicate so powerfully. At times Tokinouta seems to have an almost diffident blankness, yet at the same time it's subtle, complex and moving. Recorded live in front of an audience with no overdubs, Tokinouta feels incredibly intimate. Listening to it feels like a privilege, like being trusted with something.

Saya and Takashi Ueno – a couple as well as a band – are probably still best known through the enthusiasm of their friends Bill Wells and the Pastels, and for their collaborations. The Pastels, throwing crumbs to those still patiently waiting for their first 'proper' new album since 1997, made the lovely Two Sunsets with Tenniscoats in 2009. Wells, one of the very few people passionate and crazy enough to attempt such a thing, toured with them in the Scottish Highlands as part of a bill he put together also featuring Kama-Aina and the extraordinary singer Kazumi Nikaido. They've also collaborated with Tape and Maher Shalal Hash Baz, and Saya formed OneOne with Satomi Matsuzaki of Deerhoof in 2008.

The first three songs – 'Temporacha', 'Rain Sprinkle' (a perfect onomatopoeia for these songs), and "Summoning Sea' – establish a stately, autumnal mood. You think you know where you are, and it's a perfectly pretty place but perhaps a little undemanding, a little one-note – and then, unexpectedly, the melody of 'Summoning Sea' takes flight briefly around 3.12, and the effect is heart-melting. Then it's bizarrely jaunty interlude 'Doun Doun Doun', like the mechanicals coming on in Shakespeare, and you suddenly realise how slow you've been, and that something much cleverer is going on.

Tokinouta has to be one of the least showy and most moving records I've heard in ages. Saya and Takashi describe their music as 'DIY', which might imply a scrappiness, a sort of shambling ineptitude. But the quality that the cynical might call 'faux-naive', inherent in part in Saya's child-like vocal, belies its sophistication and its power. More than anything, Tokinouta makes me think of Vashti Bunyan's 'Winter Is Blue', of the fractured witching-hour heartbreak of side one of Patty Waters Sings, of Peggy Lee's strange Sea Shells album, and perhaps of Pascal Comelade's toy orchestra and Astrud Gilberto's cool classicism. It's really that good. Most beautiful is the barely-there ripple of 'Through The Forest To The Sea', though when I do finally pore over the English words it is 'Sappolondon' that stays with me, its lyric perfect as a William Carlos Williams poem and so short it can be quoted in full:

'I was saving the best for last
I turned away and it was no longer
The piece is gone, the peach is gone
It disappeared, gently, leaving a sweet scent
In the empty basket'

I can't think of better words to describe this wonderful record: 'a sweet scent/In the empty basket'.