Day Tripper - Lennon/McCartney

Quoted from Andy Babiuk's Beatles Gear:

p. 175: Starr used his familiar 22-inch-bass Ludwig kit for the tour with number-six Beatle drumhead. A report on the tour described a "new instrument" invented by Mal Evans. The group's roadie had fitted an additional 'ching ring' inside a tambourine, removing its skin and installing an internal rod. Then he fitted the modified tambourine to a cymbal stand. The idea, said the news item, was "so Starr could get the right sound for DAY TRIPPER during their December tour".