A few other temperament questions

[Jason Kanter]

Let's take the Vallotti as an example.

The rollingball chart shows the sizes of the intervals as red, blue, green columns, and lists the offsets below each column. For the Vallotti, the offsets from ET are listed as
    C +5.87
    G +3.91
    D +1.96
    A    0.00
    etc. to F +7.82
    and then C +5.87 again, 
because every C on the piano is tuned 5.87 cents sharp.

In your ETD of choice, you would enter those offsets. Note, the offsets on the charts are listed in the order of the circle of fifths. The ETD will want them in chromatic sequence, which I did not provide on the charts, so double-check when you copy them in order ... easy to transpose two numbers and screw the whole temperament.

Now: notice the offset for A is 0; this is in order to preserve A=440. However, the cumulative effect of the Vallotti is to raise tension an average of 1.96 cents per note. So if you want to "zero out the tension" ... i.e. fool the soundboard into thinking that nothing has really changed, perhaps preserving tuning stability ... you would then "add -1.96" (or subtract 1.96) from each of the offsets, i.e. tune C at +3.91, G at +1.95, D at 0.00, A at -1.96 cents, etc.

If you want to do these by aural methods, (and they are generally easier than ET by a long shot), you have to look elsewhere for the tuning instructions - I did not include them on my website. (I mention this possibility because you ask if you would tune an F-F temperament.)

Hope this helps. One of these days I will update the site, add chromatic lists of the offsets, maybe add bearing instructions for selected temperaments, add the Lehman Bach (which has two humps!), yadda yadda. Ask if more questions.

Jason
  ----- Original Message ----- 
  From: KeyKat88 at aol.com 
  To: pianotech at ptg.org 
  Sent: Monday, September 18, 2006 9:44 PM
  Subject: A few other temperament questions


  Greetings,

             If I finally pick a tuning and proceed, do I tune to A440? The Rollingball website .gif charts illistrate the temperament intervals from C to C. Do I start on middle C? If so, middle C of 523Hz (as in an A-440 tuning), or would I tune middle C lower?  Can I still tune an F to F procedure as I am used to for ET? 

            Also, what does it mean on the side of the Rollingball chart where it states the following sentence: "To zero out total tension change, add this to each offset"....then it gives a number, for example the Valotti has a  -1.96 below that sentence. 

           Also, on the Rollingball chart, the low C-G and E-G is different bps than octave above it. Must I follow that difference through with all the octaves C# to C#, D to D...etc, thereby giving a "stretch" to the whole piano's tuning? if that answer is yes then the whole piano is a temperament itself, and I am not copying octaves as I would do in ET!!!???? Right? Are these temperaments stretched. Woah! I have never done this before.

  Julia Gottshall
  Reading, PA       
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