Singing outdoors in what seems to be a perfectly designed open dome that suits their voices, the Group add energy and humour to their very professional voices. The tenor, of course, is the lead but the wonderful support of the other 3 singers gives him a perfect base to present exciting music.
The songs aren't long so the tour guides don't stare at their watches but if you want to lean against a brick wall at the back of the Dome, you can listen to a variety of music and really feel the energy and happiness of the singers.
If they catch you humming ro bom-bom-booming, you're co-opted into the quartet and invited to burble along in the deep background.
The Dalmatian Klapa group and others like it in other cities are doing this and changing tourism from a passive following of the flag bearing guide to a much more active appreciation of the environment of history.