Looking forward to X-axis cal option in [W] .
Give this version a try, Pavel: https://www.audiosciencereview.com/...loopback-analyzer-software.27844/post-1478232
Looking forward to X-axis cal option in [W] .
Thank you I did, but got a very very powerful amplifier suddenly! (joke) .Give this version a try, Pavel: https://www.audiosciencereview.com/...loopback-analyzer-software.27844/post-1478232
More on the subject Don, as it is interesting, at least to me. Level step is now 0.4dB, and THD, N and THD+N plots vs. power posted. As one can see, it is useful to have them separated, because THD+N (SINAD) vs. power plots sometimes do confuse the real issue. I will also post these findings into my NC252MP thread.Cause and effect is pretty clear from those, thanks Pavel! Jives with the earlier plots that imply it is mostly distortion, and I agree looks like supply drop at low frequencies.
More on the subject Don, as it is interesting, at least to me. Level step is now 0.4dB, and THD, N and THD+N plots vs. power posted. As one can see, it is useful to have them separated, because THD+N (SINAD) vs. power plots sometimes do confuse the real issue. I will also post these findings into my NC252MP thread.
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Class D behaviour is different from Class A or Class AB, we (probably both of us) are more used to live with linear amplifiers and test them. NCore has quite complicated feedback loop too handle class D issues like dead time etc., please see here and here. It might be interesting to make more detailed investigation of Purifi as well.Noise is relatively independent of frequency, but THD is higher at lower frequency, especially at 10 W and above. Supports that performance is limited by THD and not noise more so at lower frequency. I suspect the dip around 130 W in the 5 kHz curve is due to a happy coupling or resonance cancelling the distortion.
Agreed, my last class D design (for RF) was many years ago, and audio before that, so I've not kept up. Thanks for the links, more required reading, when I have some spare time.Class D behaviour is different from Class A or Class AB, we (probably both of us) are more used to live with linear amplifiers and test them. NCore has quite complicated feedback loop too handle class D issues like dead time etc., please see here and here. It might be interesting to make more detailed investigation of Purifi as well.
Thank you I did, but got a very very powerful amplifier suddenly! (joke) .
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In the top right corner box there is a correct max. power of some 282W, however the plot says 1300W ...
Log scale on X-axis for watts should be used, scale setting check box does not do it. But Paul, I am not pushing on you, for DIY purposes the SW is OK, for semi-professional I am continuing in REW use.
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[V] sweep seems to have X-axis calibrated in Vpeak rather than Vrms.
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Paul, it is much better, however still we have some minor issues.An honest mistake The X axis was using the generator level instead of the input. Will be fixed in the next beta version:
https://www.audiosciencereview.com/...loopback-analyzer-software.27844/post-1479545
Class D behaviour is different from Class A or Class AB, we (probably both of us) are more used to live with linear amplifiers and test them. NCore has quite complicated feedback loop too handle class D issues like dead time etc., please see here and here. It might be interesting to make more detailed investigation of Purifi as well.
Agreed, my last class D design (for RF) was many years ago, and audio before that, so I've not kept up. Thanks for the links, more required reading, when I have some spare time.