- Thread Starter
- #101
Not necessarily surprising given we already have THD+N measurements as a function of power for various frequencies (obviously Amir used 45 kHz bandwidth instead of 24 kHz) which show the high and low frequencies giving out first, but the log scale makes the difference less obvious at first glance.
Yes, it is in conformance with @amirm measurements of various amplifiers with NC252MP modules. I might add some system details and more measurements of my NC252MP amp.
About a half year ago I started to use a measuring system based on Topping D10s DAC and E1DA Cosmos ADC. It is not as good as Audio Precision APX555, however it has lower distortion than Audio Precision APX525. Limits shown below:
STEPS program allows me to make multiple THD vs. level measurements in one graph, however the X-axis is calibrated in Volts, not in Watts. It is the other view to the same thing as shown in my post #92. I would say that the graph in the post #92 is more revealing.
and a common THD and THD+N at 1kHz/4ohm. Not so much telling, IMHO.