That was also my initial thought, but looking at a few different plots, the most useful range can vary enormously.Gale Andrews wrote: the other person wanting it was happy if the resulting vertical scale was just 0 dB to the Preferences-determined minimum.
Sounds that have strong harmonics will tend to have big peaks and a maximum scale of 0 dB would be quite reasonable, however, if analysing low level noise (such as tape hiss), the vertical scale would need to be considerably different in order to see any useful detail. (the peaks of interest could be in a 6 dB range at around - 60 dB and would be almost invisible with a scale that goes up to 0 dB).