Tuning the bars

I watched a video about triple tuning a marimba bar using a router, by Lynxwatch.

I applied these principles to tuning my keys, but in the early stages I was not particularly successful at triple tuning so decided I was happy with just tuning as close to the fundamental as I could get.

Rather than using Baudline, which I found rather user unfriendly, I used Audacity to measure the audio spectrum of each bar as I tuned it.  My method involves opening a new stereo track and recording me playing the note near the computer's microphone.  I hold it by the nodal holes, and then tap it gently with a screwdriver handle to get a recording. I tap it several times in succession and then cut the recording back to isolate the best example in terms of amplitude and clarity. After this I select this region of the recording and analyse it using the plot spectrum tab.  This gives me data about the main peaks and lets me know whether any of the harmonics are also tuned.  I then close the spectrum plot, do some work on the bar and record again.  Again I pick the best of the new recording and add it to the previous one.  I then plot the spectrum of the new recording and keep repeating this sequence until I am close enough to be satisfied.  I may work on all the keys again later but at the minute I just want to get a double octave of keys roughly in tune with one another.

Here is my Audacity data for my E5 key.  It should be at 659.20 Hz, not 669 Hz but I think it is close enough at this stage while I am still rough tuning.

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