There is still something to be said for having an actual tuning fork. People may be interested to know you can get specialized pitches of great interest from Ragg. The Early Music Shop has some small amount of stock of rare pitches at the moment, such as A409 (the measurement of Taskin’s fork).
There is also a good range at Ragg, but some of these exotic ones above it seems they no longer make.
While on the topic of accurate pitch references, I would mention that I have done careful comparisons of phone based tuners and they can vary and disagree by up to a couple of Hertz. So please do not regard them as laboratory reference standard - they are not. Similarly with discrete electronic tuners/metronomes etc. My really good $150 Intellitune is out by 2Hz. Which is a lot.
And of course Ragg tuning forks are calibrated and dead accurate at 20C, and the pitch is temperature dependent.
