The first thing you realize when working with Benjamin Britten is that he is a thorough professional, though he lives in an era which has tended, in all branches of the arts, to glorify the amateur. It is because of his professional approach that he is so admired by orchestral musicians, despite his shyness about conducting. Any score he writes reveals a unique knowledge of instrumental capabilities, and in rehearsal he talks to the musicians in their own language – without fuss, and always with practical point. 'Strings, I'm going to beat out the very first bar, so watch me. We must be together and get the rhythm right to begin with, but after that I'm not going to spoon-feed you.' For myself, I would like to press-gang just about every star conductor under 45 and make him listen to a Britten rehearsal: the precise instructions, the knowledge of breath control applied to wind and brass instruments, the willingness to ask and take advice of a skilled player and – above all – the refusal to make rehearsals boring by talking too much and playing too little. 

The decision to record the War Requiem was taken by the Directors of Decca before the work was completed, and at that time – December 1961 – there was some thought of recording it live at the first performance in Coventry Cathedral during May 1962. Fortunately this idea had to be abandoned; for although the occasion was a great one, the musical result did something less than justice to the work, and the BBC transcription provides pretty strong evidence against those few critics who still insist on the sanctity of live performances transferred to disc. No amount of talk about 'atmosphere' will alter the fact that a great deal went sadly awry in Coventry that night. That the War Requiem survived such a series of understandable – and, in the case of a single performance, unimportant-mishaps is a tribute to its resilience. 

When it comes to recording, Britten is a joy to work with because he understands that technical developments and improvements are made solely to assist the artist towards a more accurate representation of his work. It requires much more complex and delicate equipment to make a fine stereo recording than a mono; and such equipment demands greater sensitivity on the part of all concerned. You cannot begin to make a good record with an artist whose head is so elevated that he spurns any interest in the technical side, and claims that there is no important difference between recorded sound as it can be today and as it was 10 or 15 years ago. When we wen: planning Peter Grimes a few years ago I went to Aldeburgh to talk to Britten about stereo stage production, because it was something he had not encountered before. He grasped its possibilities and limitations immediately, and discussed every move and effect in detail. 

In other words, he didn't only want to put the notes of Peter Grimes on record: he wanted to take advantage of a medium which had only just come into being. As always, he was treating the matter as a professional. 

The application of stereo to the War Requiem was a different matter, easier in some ways and harder in others. It should be remembered that there are three distinct levels or planes within the structure of the work. Their relationship to one another is fundamental in any performance, for if they fail to balance in terms of sound and perspective both the aural and emotional values of the work may be distorted. In the foreground are the two male soloists-the soldiers-and the chamber orchestra, concerned throughout with the poems of Wilfred Owen. Theirs is the world of here and now: an in tensely personal vision of man driven to an extremity of action and emotion-the extremity of war, and the grief of man for man. Beyond them range the large forces of the Mass itself; soprano soloist, full chorus and orchestra. They represent the formal expression of mourning – the world of ritual – and the liturgical plea for deliverance. Still more distant and separate are the boys' voices and chamber organ: the mystery of innocence and purity conveyed in voices from afar, at an infinite remove from the world of the battlefield. 

The deployment that emerged after discussions with Britten placed the two soldiers and the chamber orchestra on the right in a deliberately dry sort of acoustic, Partly to ensure verbal clarity, and partly to emphasize the often astringent quality of the music for the chamber orchestra (the word 'cold' appears several times in the final song as a tonal instruction to the string players). The large forces of the Mass cover the whole sound area and have a wide open acoustic: a compromise between the smudgy effect of a cathedral and the sort of reverberation desirable for a standard choral work. The boys' chorus and the small organ are on the left in the far distance. Thus, with the composer's help, we were able to embody the perspectives he had in mind when he wrote the War Requiem. 

Such a deployment imposed a tremendous strain on the composer as conductor (for the larger sections of the work there were over 400 participants spread all over Kingsway Hall). But, as always, his directions were specific: 'Chorus, in the first movement please, keep your words and the rhythm clear, but don't sing out. No emotion, no expression: it's a slow procession.' Britten has an intuitive sense not only of how to write a climax, but how to build one when he is conducting. I would mention in particular the headlong plunge into the return of the Dies Irae after Fischer-Dieskau's 'May God curse thee, and cut thee from our soul!" and the approach to the G minor cataclysm in the Libera Me. Britten is extremely modest about his abilities as a conductor, but he is alone in his doubts. It takes a real conductor to control the mighty brass accumulation between (20) and (23) in the Dies Irae, and there is not a single tape join in the passage. 

Everyone present had a sense of taking part in an historic occasion, and I think everyone worked with devotion. I shall not forget Peter Pears who, having given a superb performance of the Agnus Dei to Britten's entire satisfaction, went away to think about it quietly; and then came back an hour later and modestly asked if he might try again. He did, and the sheer perfection of that performance went into the master without alteration. 

Of the work itself I can only say that, having lived with it very closely for about four months, and having heard it upwards of 50 times, its profound impact has not lessened for a moment; on the contrary, like all great music, it yields different values on each hearing. It is a very disturbing piece. The contrasts and indeed contradictions between the three planes of its structure give the War Requiem an extraordinary tension; and their conjunction in the final section of the work is anything but a facile reconciliation. Over these final pages stand, unheard and unset, the words of Wilfred Owen with which Benjamin Britten prefaced the score: 'All a poet can do today is warn.' 

[Editorial note, 2013: In the half year following the release of this recording of Britten's War Requiem, Decca sold over 200,000 copies, making it the fastest-selling classical release up to that date.]