Alto Aviation, with roots at audio giant Bose, is expanding and last month completed a move from its old Sterling, Mass. facilities to a new, larger 14,000-sq-ft corporate headquarters and manufacturing center in nearby Leominster. The company’s founders, all retired from Bose, launched Alto about nine years ago. With the blessing of Dr. Bose, they built on the Bose tradition to create an audio system designed specifically for the business aircraft cabin. The basic system, which is ideal for a midsize business jet, consists of four speakers, four subwoofers and an amplifier. Before installation, the company performs an audio mapping of the cabin, taking into consideration such factors as seat placement and location of hard-wall cabinetry. Speakers are typically placed in the PSU, which carries the lighting and air gaspers. The idea, said Alto president Don Hamilton, is to create an audio environment in which the quality and fidelity of the sound is the same, whether the passenger is seated, standing or passing through the cabin. The company claims to have the smallest and lightest speakers, subwoofers and amplifiers on the market. A typical cabin audio system for a midsize business jet lists for $9,500 (uninstalled).