Construction
It is known for certain that the wood used included spruce for the top, willow for the internal blocks and linings, and maple for the back, ribs, and neck. There has been conjecture that this wood was treated with several types of minerals, including potassium borate (borax), sodium and potassium silicate, and vernice bianca, a varnish composed of gum arabic, honey, and egg white. He made his instruments using an inner form, unlike the French copyists, such as Vuillaume, who employed an outer form. It is clear from the number of forms throughout his career that he experimented with some of the dimensions of his instruments.
A recent study in PLOS ONE found no significant differences in median densities between modern and classical violins, or between classical violins from different origins. These results suggest that it is unlikely classical Cremonese makers had access to wood with significantly different wood density characteristics than that available to contemporaneous or modern makers.
Comparisons in sound quality
Above all, these instruments are famous for the quality of sound they produce. However, the many blind tests from 1817 to the present (as of 2012) have never found any difference in sound between Stradivari's violins and high-quality violins in comparable style of other makers and periods, nor has acoustic analysis.
In a particularly famous test on a BBC Radio 3 programme in 1977, the violinists Isaac Stern and Pinchas Zukerman and the violin expert and dealer Charles Beare tried to distinguish between the "Chaconne" Stradivarius, a 1739 Guarneri del Gesú, an 1846 Vuillaume, and a 1976 British violin played behind a screen by a professional soloist. The two violinists were allowed to play all the instruments first. None of the listeners identified more than two of the four instruments. Two of the listeners identified the 20th-century violin as the Stradivarius. Violinists and others have criticized these tests on various grounds such as that they are not double-blind (in most cases), the judges are often not experts, and the sounds of violins are hard to evaluate objectively and reproducibly.
In a test in 2009, the British violinist Matthew Trusler played his 1711 Stradivarius, said to be worth two million U.S. dollars, and four modern violins made by the Swiss violin-maker Michael Rhonheimer. One of Rhonheimer's violins, made with wood that the Empa researcher Francis Schwarze had treated with fungi, received 90 of the 180 votes for the best tone, while the Stradivarius came in second with just 39 votes.
The majority of the listeners misidentified the winning violin as the Stradivarius.
In a double-blind test in 2012 published in the study "Player preferences among new and old violins", expert players could not distinguish old from new instruments by playing them for a short time in a small room. In an additional test, performed in a concert hall, one of the Stradivarius violins placed first, but one of the participants stated that "the audience in the concert hall were essentially equivocal on which instruments were better in each of the pair-wise instrument comparisons" and "I could tell slight differences in the instruments...but overall they were all great. None of them sounded substantially weaker than the others"
While many world-class soloists play violins by Antonio Stradivari, there are notable exceptions. For example, Christian Tetzlaff formerly played "a quite famous Strad", but switched to a violin made in 2002 by Stefan-Peter Greiner. He states that the listener cannot tell that his instrument is modern, and he regards it as excellent for Bach and better than a Stradivarius for "the big Romantic and 20th-century concertos."
http://en.wikipedia.org/wiki/Stradivarius
.....τωρα ειμαι σιγουρος οτι με την βοηθεια σου θα μπορεσουμε να αναπτυξουμε μια ολοκληρωμενη θεωρια δονησεων και ιδιοσυχνοτητων περιλαμβανοντας και την συμπαντικη δονηση των πλανητων μεσα παντα απο το πρισμα της αγαπης αλλα την συνεισφορα ληγμενων χαπιων και σιροπι του βηχα(Sinecod ε? με αλλο σιροπι τα παντα..καταρρεουν) ;D
