No contest - his Lyriche Greche, which is made up of three smaller groups of settings of ancient Greek poetry. Utterly superb, and by the by possibly the single best advertisment for the 12 tone technique (without Bergian tonal references to muddy the waters
). It's a cliche, but Dallapiccola like some of his Italian contemporaries had a true lyric gift, and in these exquisite, delicate songs it's evident in abundance. One of the most striking of these songs is about a seashell, and like a seashell all the songs are delicate, irridescent - and yet incredibly strong, because of Dallapiccola's intensely contrapuntal writing.* As the cycle progresses the strongly contrapuntal nature of the songs becomes more and more apparent, and instead of being named after their tempi, they become 'Canoni', 'Variazione', 'Canon perpetuus', 'Canones diversi', 'Canon contrario motu' and so on. All very consciously Bachian, specifically very Musical Offering-y - and of course Dallapiccola has his own Musical Offering in the gorgeous Quaderno Musicale per Annalibera - but the Mediterranean warmth of the sound isn't Bachian!
One of the most beautiful experiences of my life was sitting in a cold, grey lecture room at Cambridge listening to Hugh Wood talk about Dallapiccola's life, and then put on an LP of these songs. It had me spellbound. Later, I found the score in the college music library - the strong canonic threads of the music were clearly there to see, but so was the delicacy. One of my favourite, touchstone 20th century works without a doubt, as you can see!
*This combination of vulnerablity and contrapuntal strength reminds me of late Brahms, such as op 119/1, which I think is the one Clara Schumann (no, maybe it was Brahms himself) described as a 'grey pearl', which brings us back to things marine and nacreous!.
