Murdoch's attempt to capture a slice of the 'quality' end of the gramophone market was designed by Captain H.T.Barnett, author of 'Gramophone Tips' and of technical notes (particularly relating to soundboxes) in early issues of The Gramophone. The Beltona Peridulce soundbox is in fact a 'Pianina', but with an aluminium diaphragm, before this material came into general use for diaphragms. The large, fibre-backed Pianina also formed the basis of the Duophone soundbox.
This type of floating horn is comparable to that of the Seymour Superphone and Magnaphone/EMG, although the principle had been in use from the earliest Victrolas. The use of papier-mâché also anticipates the Wilson and later EMG horns.