This advertisement opens with two quotes. The first is from Thomas Carlyle's Sartor Resartus, 'As the Swiss Inscription says: Sprechen ist silbern, Schweigen ist golden (Speech is silver, Silence is golden)'. The second is from a song in Shakespeare's Romeo and Juliet, 'Music with her silvern sound'.
The advert comes from The Television Guide, 1949. At this time sound technology was in its early days, sound in the home usually came from the wireless and the gramophone, and it was rare to own a television. The Television Guide is subtitled: 'The Handbook for the not-so-technically minded who want to get a full appreciation of the facts and phenomena behind Television'.