Why is Mina so excited over Dr. Seward’s phonograph?

Mina's fascination with the phonograph reflects a more general fascination that the novel has with gadgetry. The book is full of the latest inventions: phonographs, shorthand, electric lanterns. Part of the arsenal the group wields against Dracula is this knowledge of scientific method, reason, and the latest inventions‹which are the fruits of modern science.