I would just like to chime in and say that when I tune my harmonicas and check frequencies with a tuner I have to be very conscious about my breathing. If I apply the wrong kind of pressure or suction it will easily jump 10 to 15 cents off!
It is really not a good way to check tuning, specially if you are in the early stages where conscious breath control is difficult.
You are right that it is possible to affect tuning with variability of air pressure. I can definitely see it with my playing.
But some reeds are OK, some are 10 off and some are +/- 20 off no matter the air pressure. I know very little about
tuning of the harp - I know how to tune guitar for regular playing and for open tuning and/or slide work.
So yes - my numbers should not be treated as very reliable.
I tried to reproduce them - and they are still off in somewhat random way but they are different now then few hours ago.
I warmed the harp - not sure if sufficiently - since many lower octave valves stick like crazy. Maybe I should play it for
a long stretch before checking tuning. And once again it is not a complain - I played the Cabaret for few months then
stopped for almost two years - now I am playing it again. Sometimes it works ok and sometimes it gives resistance.
I though I could try some maintenance on my own but wanted to to have plan B in case I messed up - hence question
about reeds.
