TLA Tuning-Set CTS-32-C, Руководство пользователя

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During the measure the correction length (ld) will be calculated continuously by the formula:
ld = lp – (f_pitch / f_true * reference length
With the keys “Actual” you can achieve the display of “lp” or “ld” in the tuning program.
4.7 Filtering of partials
The low susceptibility to disturbance of the TLA Tuning Set display is achieved among other things
through a band pass filter (64 dB per octave) installed in the device. This filter suppresses all in-
coming signals of the microphone except the frequency of the tone to be tuned.
Only the frequency of the partial, which is adjusted in the set, passes the filter. This makes it pos-
sible, for example, to measure the amplitude of individual partials selectively, i.e., the inharmonicity
of a piano string.
Example: Filtering of the third partial
Filter input signal
Amplitude
Filter output signal
Amplitude
4.8 Limitation of values
The Tuning Set works in a frequency range of 20 Hz to 15000 Hz.
All adjustments of tone, concert pitch, cent or partial with a frequency result outside this range, are
suppressed.
For example, it is not possible to use the first partial on the deepest note „C_2“ or to use the se-
cond partial of the highest note g#_6.
filtering
Frequency
1. partial
2. partial
3. partial
4. partial
filtering
Frequency