I just noticed the LTSpice error log states two different THD values. Summing the squared normalized components and taking the square root in Excel gives 0,00000143047276833332% so the first value seems to be the correct one.
Now what is the second value in ()?
Interestingly the amplifier's measured performance is much much worse and closer to the value in brackets. I'm confused now
Harmonic Frequency Fourier Normalized Phase Normalized
Number [Hz] Component Component [degree] Phase [deg]
1 1.000e+03 9.669e+00 1.000e+00 -0.06° 0.00°
2 2.000e+03 1.203e-07 1.244e-08 -76.56° -76.50°
3 3.000e+03 6.289e-08 6.505e-09 107.36° 107.42°
4 4.000e+03 1.560e-08 1.613e-09 -79.82° -79.76°
5 5.000e+03 1.203e-08 1.244e-09 13.66° 13.72°
6 6.000e+03 1.280e-08 1.324e-09 150.68° 150.74°
7 7.000e+03 4.926e-09 5.095e-10 -170.64° -170.58°
8 8.000e+03 5.076e-09 5.250e-10 3.96° 4.02°
9 9.000e+03 9.867e-09 1.020e-09 -3.43° -3.37°
10 1.000e+04 1.942e-09 2.009e-10 133.98° 134.04°
Total Harmonic Distortion: 0.000001%(0.000207%)
Now what is the second value in ()?
Interestingly the amplifier's measured performance is much much worse and closer to the value in brackets. I'm confused now
Harmonic Frequency Fourier Normalized Phase Normalized
Number [Hz] Component Component [degree] Phase [deg]
1 1.000e+03 9.669e+00 1.000e+00 -0.06° 0.00°
2 2.000e+03 1.203e-07 1.244e-08 -76.56° -76.50°
3 3.000e+03 6.289e-08 6.505e-09 107.36° 107.42°
4 4.000e+03 1.560e-08 1.613e-09 -79.82° -79.76°
5 5.000e+03 1.203e-08 1.244e-09 13.66° 13.72°
6 6.000e+03 1.280e-08 1.324e-09 150.68° 150.74°
7 7.000e+03 4.926e-09 5.095e-10 -170.64° -170.58°
8 8.000e+03 5.076e-09 5.250e-10 3.96° 4.02°
9 9.000e+03 9.867e-09 1.020e-09 -3.43° -3.37°
10 1.000e+04 1.942e-09 2.009e-10 133.98° 134.04°
Total Harmonic Distortion: 0.000001%(0.000207%)
This is the official answer,
http://www.diyaudio.com/forums/software-tools/263590-whats-ltspice-doing-there.html#post4097547
http://www.diyaudio.com/forums/software-tools/263590-whats-ltspice-doing-there.html#post4097547
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.