The Bridgewater’s series Echoes of a Mountain Song makes particular sense in the concert hall given it’s renowned and extraordinary acoustic physique. Speaking of form, Sir Thomas Allen's voice is something to behold. With a number of his own japes aside concerning matureness, it is with Allen’s own words in mind that I reflect on just how excellent his voice remains, as is the colourful voice of Joseph Middleton on the concert grand. If there is anything to be taken away from art song, it is the number of voices involved bar solely the singer’s. This duo was close to perfection.

It is hard to approach comment on the performance of a national treasure and deeply respected veteran of opera and voice production. Speculatively, this may read a little more like an account than a critique. But perhaps that is more due to the fact that this was quite simply a knock-out concert, from every angle and particularly in the detail.

Firstly, the atmosphere was unfaltering. Bridgewater Hall has a particularly refined acoustic, as every component of the building – from the outer walls to the concert hall seating – contributes to its perfect balance, meaning the sound is uninterrupted by the outside world and relatively unfazed by timbre. However, with Allen and Middleton at the controls, there was not, audibly or visually, a note dropped or moment spoiled. Particularly, Middleton’s bird-song-like flourishes in Coates' Bird songs at eventide and control at the ends of songs, and for that matter his seamless entrances into each, were nothing short of brilliant. His playing was fluid and attentive. Their combined music-making was truly evocative of the landscapes and narratives it aims to capture.

It was in the polished detail that Allen’s fine performance lay. His satin baritone voice is smooth and formidable, but his character fizzed and twinkled with humour and joy. This shone through and painted the lyrics sung with exquisite diction. “Laughing” in Ireland's The Bells of San Marie was vocal and musical laughter. “Over” - the final word of Sea Fever - also displayed such mastery and execution of messa di voce, navigation of the passaggio, length and dynamics. This beauty persisted throughout the twenty-seven songs.

Allen and Middleton’s performance seemed to catalyse a transcendental feeling between composer, composition and performer, creating the illusion that the songs were written for them. Not only this, but the line between vocal and instrumental became blurred. Both performers displayed the ultimate expression of both.

When we came to the traditional songs in the second half of the programme, Sir Thomas Allen was free, hands in his pockets, so comfortably in his element. Elsie Marley was a moment of unaccompanied folk, more spoken than sung, save for the distantly lyrical beginnings of its verses. It was a bit of a shock to the system after Butterworth’s Six Songs from A Shropshire Lad, but totally fantastic and magically authentic.

A twenty-seven song (two were encores) recital is a feat for any singer. Allen is undoubtedly a master of English Song, akin to that of Fischer-Dieskau and German Lied. Their similarities show in the expression of the music and the words, an expression mirrored well by Middleton.

Finally, comment on an anecdote, as we were treated to so many by Allen during the course the evening. The songs of Michael Head drew a story linking Barbirolli (to whom the Bridgewater is a memorial) in performance to a young, concert-going Allen, and some poignant inspiration for the Echoes concert as a result. It is clear that there was an immensely personal element to this concert, which made it a very special evening.