How to band limit the excitation signal?

Why? The reasons for this are twofold:

(1)

you could probably get greater signal level out from the loudspeaker;

(2)

the bandwidth limited signal would eliminate very low and very high frequencies which could overload the loudspeaker or amplifier.

Norsonic has this as a feature on one of their pink noise generators. The signal selection can be (1) bandwidth limited 89 to 5623 Hz (suitable for 125 to 4000 Hz octave frequency bands) and (2) full bandwidth (no bandwidth limiting).

We have not investigated how much an improvement this will give in signal-to-noise ratio.

How? The band-limiting can be done by using the pre-filtering option only (You find it in the Measurement Settings toolbar) and by using a proper filter. An example of generating a filter that bandlimits the low-frequency to 80 Hz is given below.