C sharp and D flat

[Bill Hibbert]

Mike Chester:
> Could we not have an agreement about the 12 bells list
> that says a bell that is, for example, up to a given
> limit either side of the absolute pitch of the note D
> is notated as D and then say that within > the next
> given number of cents flat of this is Db, a further
> given amount flat of this is C# and a final amount flat
> of this becomes C natural?

An equal semitone is 100 cents wide, and so the boundaries between 
each note name are drawn at 50 cents. A note which is 49 cents sharp 
of C is C+49, but a note which is 51 cents sharp is called by the 
next note-name, so it is not C+51, but C#-49. In other words, the 
maximum deviation in cents you will ever see is 49 or 50.

The problem with the second part of the suggestion is that, for the 
purposes of pitching a tenor, C# and Db are the same frequency. The 
choice between them is genuinely arbitrary. One could adopt the 
convention that negative deviations are Db and positive deviations 
are C# (or vice versa!), but there is no musical basis for this.

I think it would help clear this one up if people could explain what 
they believe the difference between C# and Db to be (this is not a 
wind-up but a genuine enquiry). Dickon, you have posted on this a few 
times, perhaps you could explain your thinking again.

Bill H