Thank you for your suggestion.
MI supports ×32 SINC interpolation (i.e. ×32 upsampling) between samples in its Oscilloscope. The waveform displayed after this SINC interpolation is a much closer representation of the true continuous analog waveform, with the true peak revealed graphically. Note that in MI, the SINC mode is activated only when the number of visible samples on the screen is equal to or less than one quarter of the horizontal resolution of the waveform graph. In other words, the SINC mode will be activated automatically if you zoom in sufficiently.
We may consider adding Derived Data Points for the true peak and true RMS in the future if there is sufficient demand for this feature.
If you would like to test a DAC’s reaction to an overloaded digital stream, which is caused by overloaded recording, improper digital-domain post-processing, or overloaded synthesized data, you can generate a sine wave with a frequency of 1/4 sampling rate and an initial phase angle of 45°, using the multitone function of the MI Signal Generator, and then sweep its amplitude from a SAMPLE amplitude of 0.707 to 1. This corresponds to a true peak ranging from 0 dBFS to +3.01 dBFS, as shown below.
- SampleAmplitude0.707.png (71.49 KiB) Viewed 14164 times
Sampling Rate 48kHz, 12kHz sinewave, Sample Amplitude 0.707, True Peak: 1 (0 dBFS)
- SampleAmplitude1.png (80.75 KiB) Viewed 14145 times
Sampling Rate 48kHz, 12kHz sinewave, Sample Amplitude 1, True Peak: 1.414 (3.01 dBFS)
- SignalGeneration12kHz45DegreeAmplitudeSweep.png (31.71 KiB) Viewed 14164 times
Signal Generator Setting: Amplitude Sweep from 0.707 to 1, 12kHz sinewave with initial phase angle of 45 degree.
