Today, you heard - carefully chosen for Remembrance Sunday -

Pie Jesu, and Agnus Dei, from Faure's Requiem
An introduction to the last hymn - the tune for "God of the nations"
"Nimrod", from Elgar's Enigma Variations

The truth will out - the new "Gaelic-sounding" tune is actually called Govan Cross - because that's where it first saw daylight. I'm afraid it is no more Gaelic than your organist! However, if the proof of the pudding is in the eating, then the proof of the tune must be in the singing. And it did turn out to be singable!