Spectrum analysis - Q&A

The resolution in the low-end part of the spectrum can be increased by increasing the FFT Block Size setting.  At the same time, a lower Avg Time and an increased Overlap setting can be both recommended so that the spectrum is updated more frequently thus giving a more "fluid" looks.  These recommendations are especially relevant if project's sample rate is 96000 or higher.  Competing analyzers may offer pre-selected FFT analysis settings.  On the other hand, Voxengo spectrum analyzers give you more choices for FFT analysis customization.  Note that plugin's FPS setting and host application's audio block size also affect visual refresh rate.

Individual components of the spectrum are usually much quieter than the summary energy, so getting readings across the spectrum lower than the overall output level is a norm.  Also take a note of the "Slope" mode setting which applies a constant slope over the spectrum making lower frequencies appear quieter.

Pink noise has -3 dB/oct slope.  Yes, you'll need to configure 3 dB slope in the spectrum mode editor, to make it look flat, since the default slope is 4.5 dB/oct.