Violin ABX double blind test: Modern vs. Stradivarius

A quick test of my ability to audibly discern a Strad vs. modern violin by "Running the X's only" in Foobar ABX, a form of double blind test. Note, this was a much more difficult test than most Foobar ABX tests because during the test each trial's sample, X, was examined on its own WITHOUT the benefit of listening to the established anchor sounds of A and B mid-test for comparison, which is usually allowed for in traditional ABX testing. Running the X's is a much more strenuous test since you have to rely on your audio memory rather than your echoic memory (the more precise memory for a sound which dissipates 4 seconds or so after having just heard the sound).
I correctly ID'd version B as the Stradivarius 9 out of 10 times, in only a little over a minute. I've also aced this test getting ten correct out of ten trials, but this was my very first time video recording a test. My statistical significance level determined at the end beats the common p=.05 level. I used the auto level matching feature called ReplyGain in Foobar ABX although I don't normally advise using it and instead recommend only using pre-level matched files, as is. The source was provided from my download of the NPR segment discussing the scientific paper published in the Proceedings of the National Academy of Science, conducted by Claudia Fritz, et al, www.npr.org/sec...
Manually level matching by adding .7dB to one sample, instead of using the auto feature, in an audio editor prior to testing, resulted in the same findings.
Although my perception is that I am keying on a change in timbre it is possible that a variation in the human musician's performance from take to take is influencing me. Supposedly the musician playing the violin is also double blinded. Read the original paper for details.
My tutorial on how to easily download and use foobar ABX: • Hi-Res Audio Test HOWT...
It teaches you the TRUTH.