Clavichord.In the clavichord each string is struck by a small piece of metal called a tangent. Its touch-sensitive action allows great expressiveness in playing, although its small size and softness of sound
The Pianoforte until the end of the 18th century – The Salon Music Blog
Checking Out: This is NOT a Piano by Audio Brewers - Sample Library Review
The Whispered Spell of the Clavichord | The New Yorker
Introduction of Tangent Piano - CMUSE
Longman & Broderip - Eric Feller Early Keyboard Instruments Collection