Only a handful of controlled tests have been conducted and listeners failed to identify or prefer the Strads. None of the experiments were very big so there might be a perceptible difference that can be detected with more statistical power. Blinding the eyes and noses of top level musicians might bias the results.

It is very difficult to obtain access to the instruments. The general sentiment from musicians and collectors seems to be that they don't want a bunch of scientists to come into their world and tell them that what they are or are not hearing or they just don't understand why controlled tests are required.