Tuning forks based on 256Hz etc. response to AmbassBob enquiry

Yes such things do exist. I had to buy one for a choir used for "Longitude" the Channel 4 film on John Harrison which I worked on a few years ago.
I found it in a specialist music shop in London, and eventually left it with the choir master at Oxford University.
You should be able to find a source easily on the net.
Search on "tuning forks".

Charles Lucy - lucy@harmonics.com
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