Niggun Neshama. Everyone's heard it, probably at a wedding or live in concert. In my unqualified opinion, it's one of R' Shlomo Carlebach's finest compositions that remained professionally unreleased during his lifetime. A personal recording or two has surfaced, though.
Shlomo Katz' bonus track from V'Hakohanim is a live recording from the first time Shlomo ever played the niggun - at a R' Shlomo yartzeit concert in Yerushalayim. This is always amazing to listen to.
Shlomo Katz is the artist responsible for making Niggun Neshama as popular as it is be really introducing it to the Jewish music world. I was privileged enough to be learning in Israel when he began his one-man campaign to get the Jewish world singing and dancing with this lively niggun, and let me tell you, hearing it that first year of its popularity was magical. We ran from concert to concert of Shlomo's to be able to hear the niggun just one more time.
Mind you, this was before it was played to death at every single wedding in America, Israel, and everywhere else across the globe. I was once at a wedding where they played it no less than three separate times. Whenever the dancing began to lull, they started up Niggun Neshama and everyone was back on the dance floor. Cheap trick, but it worked...
I once asked Shlomo why he never recorded the song in the studio for his album, and he replied that you simply can't capture that same power and energy found when the song is performed live. He was right, and while there are nice versions of Niggun Neshama that have been recorded (see below), they do lack that magic spark of the live concert performance.
Eitan Katz' acoustic version from Unplugged is quite nice, perhaps the finest overall studio recording of the niggun. There is just a sense of quiet energy that pervades throughout.
Yehuda Green's rendition from Land of Your Soul is probably the best studio recorded fast version. It definitely makes you want to get up and dance, but it's not the same as hearing it live...
Yehuda! (click "Niggun Neshomele") took the song, jazzed it up, and made it lose all its natural appeal, IMHO. He even changed the vocalization to "Hai-dee-dee-yo-oh" - who knew that changing the "words" to a niggun would affect it so adversely!? Every other artist out there that tried to make their own spin fared similarly, ignoring the inherent greatness that is already there while trying to "improve" it - I'm looking at you, Ohad and the Kinderlach.
Worse yet is the chazanim who, in an attempt to be "with it" (this remark is particularly directed to the older gentlemen midde aged and above) who think it's hip to throw in this niggun while leading the davening in shul. It just doesn't work - not for Lecha Dodi, not for Kedusha, not for Anim Zemiros, nor any other time in davening.
First, you can't just sing Niggun Neshama without a guitar and expect to pull it off. It ends up being too fast, too high, or too repetitive. Niggun Neshama only works fully when it's in the hands of a master devotee of R' Shlomo's music, such as the first three artists I mentioned above.
Second, there are too many syllables in Niggun Neshama to put words to it. This is a problem similarly found with Shlomo's Niggun Nevo. The first part just doesn't fit, though the second does, believe me, I've unsuccessfully tried it out for Lecha Dodi. Anyway, the chazan attempts to cram the nai-nai-nais into words and ends up splicing syllables and vowels as he shoves the proverbial circle peg into the square hole. Now, not only is everything ill-fitting, but now the chazan isn't even saying the proper words of the tefillah, and that is a big no-no.
Although the heyday of Niggun Neshama's meteoric rise to popularity are long over, and it has rightfully established it's place as a long-time favorite, I still see chazanim mistakenly try to utilize it to this very day. Enough already! Enjoy Niggun Neshama for what its truly worth, but don't spit on it anymore with failed attempts to spice up davening!