Daqarta
Data AcQuisition And Real-Time Analysis
Scope - Spectrum - Spectrogram - Signal Generator
Software for Windows
The following is from the Daqarta Help system:

# Standard Musical Note Frequencies

The equal-tempered scale of western music is based upon an octave (frequency doubling) that contains 12 notes, or "semitones", each of which is 1.059463 (the 12th root of 2) times the one below it.

The standard musical tone frequencies of the equal-tempered piano keyboard are tabulated below, but you can find others by extending the series. To find the same note letter in the next higher octave, just multiply by 2. To go down one octave, divide by 2. For example, C0 = C1 / 2 = 32.703 / 2 = 16.352 Hz.

You can compute the frequency of any MIDI note N from the following, where N is valid from 0 to 127:

Frequency = 440 * 2^((N - 69) / 12).

```Note    MIDI     Hz      Keyboard
A0      21     27.500
A#0     22     29.135  ---|||||||
B0      23     30.868  __________
C1      24     32.703
C#1     25     34.648  ---|||||||
D1      26     36.708
D#1     27     38.891  ---|||||||
E1      28     41.203  __________
F1      29     43.654
F#1     30     46.249  ---|||||||
G1      31     48.999
G#1     32     51.913  ---|||||||
A1      33     55.000
A#1     34     58.270  ---|||||||
B1      35     61.735  __________
C2      36     65.406
C#2     37     69.296  ---|||||||
D2      38     73.416
D#2     39     77.782  ---|||||||
E2      40     82.407  __________
F2      41     87.307
F#2     42     92.499  ---|||||||
G2      43     97.999
G#2     44    103.826  ---|||||||
A2      45    110.000
A#2     46    116.541  ---|||||||
B2      47    123.471  __________
C3      48    130.813
C#3     49    138.591  ---|||||||
D3      50    146.832
D#3     51    155.563  ---|||||||
E3      52    164.814  __________
F3      53    174.614
F#3     54    184.997  ---|||||||
G3      55    195.998
G#3     56    207.652  ---|||||||
A3      57    220.000
A#3     58    233.082  ---|||||||
B3      59    246.942  __________
C4      60    261.626     Middle C
C#4     61    277.183  ---|||||||
D4      62    293.665
D#4     63    311.127  ---|||||||
E4      64    329.628  __________
F4      65    349.228
F#4     66    369.994  ---|||||||
G4      67    391.995
G#4     68    415.305  ---|||||||
A4      69    440.000     Concert A
A#4     70    466.164  ---|||||||
B4      71    493.883  __________
C5      72    523.251
C#5     73    554.365  ---|||||||
D5      74    587.330
D#5     75    622.254  ---|||||||
E5      76    659.255  __________
F5      77    698.456
F#5     78    739.989  ---|||||||
G5      79    783.991
G#5     80    830.609  ---|||||||
A5      81    880.000
A#5     82    932.328  ---|||||||
B5      83    987.767  __________
C6      84   1046.502
C#6     85   1108.731  ---|||||||
D6      86   1174.659
D#6     87   1244.508  ---|||||||
E6      88   1318.510  __________
F6      89   1396.913
F#6     90   1479.978  ---|||||||
G6      91   1567.982
G#6     92   1661.219  ---|||||||
A6      93   1760.000
A#6     94   1864.655  ---|||||||
B6      95   1975.533  __________
C7      96   2093.005
C#7     97   2217.461  ---|||||||
D7      98   2349.318
D#7     99   2489.016  ---|||||||
E7     100   2637.020  __________
F7     101   2793.826
F#7    102   2959.955  ---|||||||
G7     103   3135.963
G#7    104   3322.438  ---|||||||
A7     105   3520.000
A#7    106   3729.310  ---|||||||
B7     107   3951.066  __________
C8     108   4186.009
```

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