My mistake ... my noise level was far too high. Additionnally, the noise
with amplitude lower than LSB must be added to a full-scale range sine wave
to be dithered amongst the various quantization bins. If anyone is interested,
I updated http://jmfriedt.org/quantization.pdf which (I believe)
I wanted to demonstrate quantization noise (V_q^12/12/fs noise floor)
with GNU Radio and somehow my demonstration is failing. I am trying
http://jmfriedt.org/untitled.png (or http://jmfriedt.org/untitled.grc)
following the chart of the Quantizer. Somehow I had already noticed
that the Qt Freq Sync
