Many composers have their quiet helpers, doing anything from filling in tax returns to sharpening pencils. For most British music lovers, however, the role of amanuensis surely conjures up just one image: that of Eric Fenby, who died earlier this year.

Image is the right word, for the abiding view - of the ailing Frederick Delius impatiently dictating his pent-up music to this young assistant - was a product of the famous Ken Russell film about the composer. As recalled in Fenby's words in the programme of Tuesday's Wigmore Hall memorial concert, that was also how be remembered Delius when listening to one of those late pieces, so painfully written by dictation. Music's power as a shorthand for memory is undervalued, but surely not be Delius fans. His music, after all, unlocks the sort of nostalgic memories we never thought we had.

That seemed clear from the Cello Sonata of 1916 that began the musical part of the evening, after a moving tribute to Fenby's work from The Delius Society's current president, Felix Aprahamian. Its sonorous phrases reached up from the depths of the instrument's lowest string as if made for the velvet legato of Julian Lloyd Webber. In fact, they were written for the Russian cellist Alexandre Barjansky, but Lloyd Webber was playing Barjansky's cello, which was nearly the same thing. A heart-stopping moment that verged on the edge of sound formed the core of the slow movement. From this, the rest of the music advanced and receded.

As in the Second Violin Sonata of 1923, played in Tertis's viola version by Philip Dukes with pianist Sonia Rahman, there was musical eloquence of a different order from the picturesque note found in the great programmatic pieces.

For those who love Delius of the "abstract" music best, this was, indeed, an ideal concert; and with Tasmin Little and Piers Lane also playing the Third Violin Sonata, there was no escaping the sense of a corpus of chamber music equal at least to Elgar's, yet still neglected.

The Third Sonata of 1930 was Fenby's transcription; its limpid rhythms and touches of pure Delius in the scherzo's meno mosso were an apt memento to the amanuensis. His role as a vessel for such inspiration implied a mentality the opposite of his atheistic master's. You could tell as much from two Fenby originals with holy words and themes. A set of evening canticles, though written in 1932, bore no trace of pagan Delian harmonies.

In For Music on the Eve of Palm Sunday from the same year, also superbly revived by The Elysian Singers of London, conductor Matthew Greenall, a mood of sadness was not just part of the text in question.

It was a touching piece, and one that made you wonder about the price of devotion to genius.