[LAD] 'A' note Tuning Range

[linux at justmail.de]

PS:

+-50 Cent makes sense, since it's half of a semitone interval, see
the Information taken from
http://www.sengpielaudio.com/calculator-centsratio.htm:

Interval 	                Frequency ratio    cents
Semitone or minor second 	1.059463 : 1 	   100

Here's a Table of Cents Difference for some frequencies close around
440 Hz: 
Frequency 	Difference
435 Hz 	        −19.78 cents
436 Hz 	        −15.81 cents
437 Hz 	        −11.84 cents
438 Hz 	        −7.89 cents
439 Hz 	        −3.94 cents
440 Hz 	        ±0 cent
441 Hz 	        +3.93 cents
442 Hz 	        +7.85 cents
443 Hz 	        +11.76 cents
444 Hz 	        +15.67 cents
445 Hz 	        +19.56 cents
 
So, the conversion factor 4 cents / Hz is valid for the purposes of
tuning as an exception only very close around 440 Hz. There is no
conversion from Hz to cents and vice versa. Statement: Cent is a
logarithmic unit of measure of an interval, and that is a dimensionless
"frequency ratio" of f2 / f1.