Originally Posted by
elcruxio
Not exactly sure what you're asking here but to clarify:
Spoke lengths have variation. You as a wheelbuilder should know this. If you buy a bunch of spokes at say, 290mm lengths, some might be 290,5mm while some might be 289,4mm. Due to spoke head and elbow variation the spokes might seat at the hub at different "heights" making the spokes effectively vary in length after they've been threaded in the nipple. Rims may have variation and a 1mm hop at a pinned joint isn't unheard of no matter how much you crank up the tensions there.
So you end up with spokes which have different effective lengths. Scale length of a string or wire alters the tension required for achieving the same pitch. So different effective spoke lengths mean that in order to achieve the same pitch, they will be at different tensions. You won't be able to match tensions with pitch alone, which means pitch isn't the fine adjustment you think it is.
This is stringed instrument 101. If you wish to refute any of the above, you may want to read up on stringed instruments, how they're tuned, what scale length is etc.
And that's all before string crossings come into play.
The sound the a piano string or a spoke makes is based on the length and tension of the exposed part of the string or spoke, not what is down on the other side of the nipple or fret. That's 101 - the violin doesn't know how much string is wrapped around the tuning peg. And the location of the flange, spoke crossings and rim are all very concentric, so the distance, tension and tone of the spokes at similar tensions are very close. (The tone you're looking for is produced between the rim and the touching spoke cross.) Otherwise, you couldn't true a wheel until it is hard to see it spinning.
However, you aren't going to tune all the spokes to exactly C. As I stated, using tone - which requires no music training - is a more accurate method to find variations in spoke tension than your typical tensiometer. And that's because tensiometers are more difficult to detect small differences in tension because they are relatively crude devices with arbitrary placement along the spoke. If you were using embedded digital strain gauges, that would be better than tone, but we don't use those.
You also seem to be unaware that using tone is a common practice - not something I've invented. So you are, once again, opening your pie hole about something you know nothing about and objecting to things you don't understand - like what part of a musical instrument makes the tone. Plucking or tapping the spokes is a quick, simple method for identifying large tension variations between pairs of spokes and evening them out (that might be missed using a crude tensiometer), which leads to more stability in the wheel build, and guards against damage from too high or too low individual spoke tensions.