Here is a simple spreadsheet to assist with tuning two voiced melodeons: Melodeon Tuning Spreadsheet (Excel).
It has been set up for, and contains working data from, my D/G Hohner Pokerwork retune. I created it for two main purposes: 1) to plot the existing tuning; 2) to calculate the amount of de-tune for a Viennese tuning with an equal beat all the way up the scale (also known as Dedic tuning from Ian Dedic). I also used it to measure the tuning on a fairly new Serenellini melodeon with drier tuning, to get a better idea of what the tuning of a newish mid-range melodeon is like.
Some notes on using the spreadsheet for those who don’t want to find out by fiddling:
- leave the “Notes Lookup” sheet alone; it contains the look-up from the piano key numbers to the note name and frequency.
- On the sheets “G Row” and “D Row”:
- change the entries in the “Piano Key” column if your button layout or keys are different; “Note Name” and “Concert Freq” change automatically.
- If you want to find the tuning to achieve a constant beat frequency, alter the values in cells F3 and G3. I have chosen 4Hz (beats per second), which is in the tremolo range, and set this as -2Hz/+2Hz for Viennese tuning.
- Alternatively… it is common for accordions to be tuning with tapering amounts of reed de-tuning going up the scale, with the beat increasing somewhat. Entering values into row K will compute the beat frequency in row L.
- The sheets “… Measurements” should automatically populate the left-most columns. This should be mostly self-explanatory. I made columns to record measurements with the reed in the box and on the reed block on a tuning table, computing the difference (“delta”). Since tuning on the table is far easier than in the box, I use this to estimate a correction to my target tuning when using the table.
- The “block hole number” is just a reference to my numbering of the holes on the chord block… its very confusing working out which reed is which!