There are three main analysis modes you can use. The octave band RTA is the classic analyzer with a logarithmic x axis and looks like this:

The resolution is set to 12th octave, with fast time averaging. The input signal in this case is a pink noise signal band passed at 1kHz, generated with my Filtered Noise Generator. The resolution can also be set to wider bands.

You can also view the frequency response with a linear frequency axis. This graph is calculated via an FFT. The input signal here is a music signal.

Below is the oscilloscope view. The signal shown is a 1kHz sine wave at full level generated by my Test Tone Generator.