I should have said more carefully what my finding was. I calibrated Tunelab at home using the A440 tone from the website I mentioned. (Checked also with my A440 tuning fork). I then COMPARED the reading from the 440Hz website tone on my PC at home, to that on several other computers and found I got a stationary display on the others. This could of course mean that all the soundcards I encountered were off by exactly the same amount! I don't have any other source than my tuning fork and website tones for an accurate A440. (I found the US telephone tone tricky to use and was unsure of its transatlantic accuracy - and the vagaries of telphone handsets could be greater than of soundcards). At some point I'm sure I could find someone with the right equipment in the large community college where I work, to produce a 440Hz tone of known accuracy. Or maybe not! It kind of brings us back full cuircle to the original post, and the undependability of peoples ideas (and tuning forks) of A440! Best regards, David. "There is no magic way to get a tone that is more precise than the quartz crystal in your sound card. I have a sound card that has a known offset from its calibration in sound generating mode in TuneLab. When I go to that website and play A400, I get a tone that is off by exactly the amount indicated by the TuneLab calibration. So if you get exactly A440, then you aare just lucky that your soundcard was not very far off. Robert Scott Ypsilanti, Michigan"
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