Aside from the limited repertoire and availability of mechanical instruments (such as music boxes), the only way to hear music, before the advent of player pianos and electricity, was to perform it oneself or to attend a live performance. With regard to stage works, although operatic performances were available, certainly few people could afford to hear operas many times over to gain a thorough knowledge of a work. Operatic full scores (a vertical alignment of all performers' parts) were rarely accessible to the public at large, but reductions for voice and piano and arrangements of them as well as compositions based on themes from them (as, for example, Liszt's Reminiscences de Don Juan) were available. Indeed, it was through these transformed versions that the music was disseminated and popularized.