Ross Daly, Union Chapel

Much gnashing of teeth among Union Chapel supporters: a neighbour has invoked local noise regulations, with the result that concerts amplified like Ross Daly's will no longer be on the menu. This is an economic blow, admits boss Julia Farrington, who had been depending on revenue from these concerts to finance the chapel's restoration. Then she adds: "But it's also an artistic opportunity."

She points out that the chapel - with its carved, high-domed ceiling - has a unique acoustic, which has been employed to magical effect: Bjork singing unamplified with the Brodsky Quartet was one instance; jazz pianist Abdullah Ibrahim and the Corsican a capella group A Filetta have been others. What we need, she says, are sound engineers "who dare to turn the volume down and let the building do the work, plus musicians who use their ears".

The trouble, she says, is trying to persuade money to follow such an idea, "and make viable business from such a stance". This is a significant moment. We're used to seeing musicians like Salif Keita and Youssou N'Dour going acoustic, and promoters have long grumbled about the way their stars' art - so refined on CD - gets so distorted live. But for the director of a leading venue to come out in these terms takes courage.

Anyway, on came Daly as we shan't hear him at the Union any more. This Irishman has gone native in Crete to such a degree that he's mastered all the local instruments: supported by zither, strings and hand-drum, he presented a wonderful mélange of Greek andTurkish melodies. Some of these would not have been heard in this space without at least some amplification, but there were times when the decibel-count went so high that all detail got lost in the sonic soup. I hope he comes back when the chapel reopens in the autumn: then we may get a better chance to appreciate his art.

No such problems at the Queen Elizabeth Hall, where Parissa and the Dastan Ensemble invited us to join them in celebrating the Persian New Year. The amplification allowed the oud, spike-fiddle and tar to reach every corner of the hall, but it in no way smudged their delicately inflected sounds. Parissa is probably the greatest exponent of Persian classical song, but she's not allowed to serenade mixed audiences in Iran: hence the large number of Iranians here. Her manner suits the visionary poems she sings - eyes closed, hands outstretched in prayer - and the intensity of her expression rises and falls as though propelled by divine winds. This was a magnificent performance, beautifully structured to let the strings take their turn in the limelight over a hypnotic drum accompaniment: if you missed it, Network's latest CD Shoorideh will let you savour this group's spare and subtle art.