
Instruction Manual for DAC2 HGC and DAC2 L with
2.X Firmware
Page 44
Graph 4 - FFT 1 kHz
The 1 kHz FFT analysis demonstrates the low harmonic distortion of the DAC2. Second harmonic
distortion (2 kHz) measures about -115 dB, while 3rd harmonic distortion measures -128 to -130
dB.
The rise at 0 Hz is normal in an FFT analysis and is not an indication of noise. This 32k point FFT
analysis uses a Blackman-Harris window with 16x power averaging, and spans a frequency range
of DC to 32 kHz.
Audio Precision
DAC2 - FFT 1 kHz, 0 dBr = 0 dBFS = 23 dBu
DAC2 - FFT 1 kHz.at27
Color
Sweep
Trace
Line Style
Thick
Data
Axis
Comment
Cursor1
Cursor2
1
1
Green
Solid
4
Fft.Ch.1 Ampl
Left
*-115.268 dBr
*-128.290 dBr
1
2
Red
Solid
4
Fft.Ch.2 Ampl
Right
-115.954 dBr A
-130.429 dBr A
-160
+0
-140
-120
-100
-80
-60
-40
-20
d
B
r
A
-160
+0
-140
-120
-100
-80
-60
-40
-20
-115.268
-128.29
d
B
r
A
0
3.2k
200
400
600
800
1k
1.2k
1.4k
1.6k
1.8k
2k
2.2k
2.4k
2.6k
2.8k
3k
2.00391k
2.99961k
Hz
dx=.995695 kHz
dy=-13.022 dB