This measurement was designed to work with decent hardware like the Focusrite. This is why we only look at the performance of the 6 LSBs instead of all the bits. I crank up the input gain so the measurement device's accuracy hardly matters. BTW, the Focusrite 2i2 is actually pretty good for measurements. As always, I recommend balanced inputs or probes, even if output is single ended. This is what else you will need: My special WAV file. Precision triangle waves 16 bit with code words for -32 to 32, each repeating three times. ARTA or something that will record the input. WAV player that will let you set bit depth. Output of values to a .TXT file. I used ARTAs sample export format. The piece you don't have is my custom code to create the visualizations. This is still in development. The code is utter shit... not documented, badly formatted, not following any code standards. There are still avenues I would like to explore. This is new ground to my knowledge, unless JA has already written a book about it which I am not aware of.