TuneLab Question

[Robert Scott]

Dimce writes:

>>>>
Anyone out there can tell me how can be taken MANUALLY measurements of the
partials below A4 with TuneLab program. I tried as it is said in the help of
the TuneLab but noting shows up in the graphical window. For example for A3:
I measure the first partial as 0.00 then second, third, and fourth. In the
View menu, inharmonicity measurements ( most recent) I click Apply, In the
All inharmonicity measurements they show up. In the graphical window they
are messing (there are not red lines for them.)
<<<<

Dimce, in the graphical tuning editor, what intervals have you selected
for display in the "Options" section?  The inharmonicity guide lines will
only appear for intervals you have selected; and then, only if the
inharmonicity measurements you have taken are sufficient to determine 
the beat for the selected interval.  In your example, you measured A3 
for the fundamental, 2nd, 3rd, and 4th partials.  If you are using the 
default tuning partials, then A3 is tuned using the 2nd partial.  A4 is 
tuned by the fundamental and so is A5.  Therefore the single inharmonicity
measurement that you took (for A3) is enough to determine the
4/1 double octave A3-A5.  If you have selected 4/1 double octaves for
display, then you should get a red guideline coming out of A3 and extending
to A5.  Notice that starting with the tuning curve you need to know
the inharmonicity of the 2nd and 4th partials of A3 to determine this
beat rate.

You might be wondering about the single octave A3-A4 and why there is
no red guideline for this interval.  That is because you don't need any
inharmonicity measurements to determine the A3-A4 beat rate from
the tuning curve.  A3 is tuned by the 2nd partial and A4 is tuned by
the fundamental.  Therefore both A3 and A4 are tuned to approximately
440 Hz, and the beat rate for the A3-A4 interval is determined directly
from the difference of the A3 and A4 stretch numbers in the tuning curve.
Whenever the interval can be determined without knowledge of inharmonicity
measurements, then TuneLab uses a green horizontal guideline to indicate
that interval.  And if you select 2/1 single octaves, you will see a
green guide line coming out of A3 and extending to A4.

Remember, the general rule is that red inharmonicity guidelines can
appear on the graphical tuning editor for all intervals whose beat
rate can be deduced from the tuning curve plus the inharmonicity 
measurements.  For example, suppose the tuning curve specifies the
stretch for A3 (2nd partial) as -1.2 cents and the stretch for A5 (fund.)
as +1.1 cents.  Furthermore, suppose your A3 inharmonicity measurement
was 0, 1.3, 2.7, 4.5 cents for fund. to the 4th partial.  Then the
4/1 double octave A3-A5 would be  1.1 - (-1.2 + 4.5-1.3) = -.9,
so the double octave would be .9 cents narrow, and the red guide line
from A3 should extend to .9 cents above the tuning curve at A5.  So
if you can raise A5 in the tuning curve by .9 cents, the tuning curve
will hit the other end of the inharmonicity guideline exactly, and the
4/1 double octave A3-A5 will be beatless.

I hope this helps.

-Robert Scott