In the piece on music on "Strange Side of Jewish history" from the Yated it says "“It has been said that the only [original] tune that remains to us is the niggun ‘L’Dovid, Hashem tzuri,’” he writes. “There are two reasons to say this, first, because it is a fast tune, rising in tempo, like a real martial song, and secondly, it is amazing that every Jew, everywhere, whether in Africa, Asia, or Europe, uses the same tune for this psalm. This is amazing, because they do not share any [other] tunes of prayer or avodah, since in Arab countries all the prayer tunes are Arabic, and in the lands of Edom the tunes are of Edom, whereas for this psalm they all use the same tune. “I traveled in many of the large countries of these places, investigated the matter, and found that it was true. This is a major indication that this tune is the only inheritance left from our forefathers and there is nothing else.”
What song is "L'Dovid, Hashem tzuri"? I know of L'Dovid, Hashem ori, which is Tehillim 27, but what is "L'Dovid, Hashem tzuri"? Thanks.