How can SSP help? What other gear would you recommend?
SignalScope Pro includes tools for narrowband (FFT) and fractional-octave-band spectral analysis (whole and 1/3-octave), as well as a built-in test signal generator, multi-channel level meter, oscilloscope, and acoustic calibration capability. However, you may be better served by Electroacoustics Toolbox, which includes a dual-channel analyzer that can measure frequency response magnitude and phase, coherence, group delay, and impulse response.
You can download either or both apps and give them a try for up to 30 days, to see which meets your needs the best.
For hardware, you will need good measurement microphones and an audio interface with enough mic inputs. In my experience, MOTU's audio interfaces are excellent for measurement purposes. You might want to check out the 8pre if you need multiple phantom-powered XLR inputs.