On Shabbat Zachor (the Shabbat before Purim, when Parashat Zachor is read) the S&P insert a longish liturgical poem by R Yehudah Halevi into Nishmat Kol Hai. Nishmat contains the rhetorical phrase "God who is like you?" (mi chamocha), and this is used as an introduction to the poem, whose title is "Who is like you?, there is none like you!", praising God for the miracles of the Purim story.
The entire pizmon, which takes at least 20 minutes, is chanted by the choir and congregation. The last line of each of its four sections being repeated by the hazzan in a more elaborate tune.
Some other Sephardi communities also chant this poem on this Shabbat, but do so either before or after the Torah reading. For more on the customs of Purim, see the companion site to this one here.
Mi Chamocha Ve-en Kamocha
Here's the full text in a PDF file, scanned from the prayer book of the London S&P:
Mi Chamocha full text (PDF Document)
Here's the line in Nishmat when the pizmon is interposed. The first recording is the way the line is usually sung; the second has the change that warns of the new content about to be introduced.
The opening line of the actual poem:
♫ Mi Chamocha - Introduction [JC]
The chant used throughout:
♫ Mi Chamocha - Main [JC]
The last phrase of each of the four sections, which is chanted by the congregation and then repeated by the hazan:
♫ Mi Chamocha - Reprise [JC]
The poem concludes with a reference to the miracle of the splitting of the red sea, bringing the focus back to the original context of Nishmat, which is then continued as usual.
Comment: The poem itself is a marvelous literary tour-de-force, overflowing with clever biblical references while maintaining the metre and rhyme. The London chant, however, is of indifferent musical interest, and strangely, the reprise sung at the end of each section bears little resemblance to the chant that precedes it. Interestingly the reprise more closely resembles the New York version of the chant. This suggests that the London congregational singing of this rather long - and to many congregants difficult-to-read - poem, may have resulted in a "dumbing down" of the the tune over the years, which may originally have resembled the New York version more closely.
Here is the New York chant for the verses:
The Megillah is read meticulously, but the traditional London S&P chant does not follow the cantillation marks.
London Version of the Megillah Reading
♫ Esther_I [HB]
♫ Esther_II [HB]
♫ Esther_III [HB]
♫ Esther_IV [HB]
♫ Esther_V [HB]
♫ Esther_VI [HB]
♫ Esther_VII [HB]
♫ Esther_VIII [HB]
♫ Esther_IX [HB]
♫ Esther_X [HB]
Amsterdam Version of the Megillah Reading
♫ EstherNL_1 [Revd. Nunes Nabarro]
♫ EstherNL_2 [Revd. Nunes Nabarro]
♫ EstherNL_3 [Revd. Nunes Nabarro]
♫ EstherNL_4 [Revd. Nunes Nabarro]
♫ EstherNL_5 [Revd. Nunes Nabarro]
♫ EstherNL_6 [Revd. Nunes Nabarro]
♫ EstherNL_7 [Revd. Nunes Nabarro]
♫ EstherNL_8 [Revd. Nunes Nabarro]
♫ EstherNL_9-10 [Revd. Nunes Nabarro]
This file has the four sections that are chanted by the congregation:
♫ EstherNL_cong [Nachshon Rodrigues Pereira]
The source for the Amsterdam files is here.
The source for the Amsterdam four sections is here.
For more on the customs of Purim, see the companion site to this one here.
Note: The illustration is of marzipan stuffed dates, which is a popular Purim treat among some S&P, though certainly not across the board, and with nowhere near the popularity of Hamantaschen! These are dusted with sugar, but the more professional - and delicious - ones are covered in a thin, crisp, toffee glaze.
Note: The megillah shown is from Amsterdam.