The musical instruments of today cannot sound perfect whatever modern acoustic technologies we use for designing them and whatever compex chemical substances we synthesize for providing them with a perfect sound. Of course all the best musical instruments manufactured today are hand-made, yet they don't sound half as great as the ones produced by the masters of the past - Amati or Stradivari. The modern carving and woodworking tools were not available to them; and neither could they get the most precious wood from other continents or synthesize carbon bodies of any perfect shapes; they didn't have the equipment necessary for diagnosing the sound qualities of bodies of violins, violas, cellos and double-basses they designed. Yet the instruments they produced several centuries ago have brilliant sound characteristics, which weren't rendered to present day.
According to some sources the only thing cannot be retrieved is the formula of lacquer they used for covering the instruments