books.google.com.ar - There is a wide field of tasks left that can only be satisfyingly attacked with the help of old-fashioned analogue technology, and one of the most important are amplifiers for analogue signals. The strongly expanded content of the second edition of 'the sound of silence' leads to affordable amplifier...http://books.google.com.ar/books/about/The_Sound_of_Silence.html?hl=es&id=eZLUGOACGv8C&utm_source=gb-gplus-shareThe Sound of Silence
