I need to do some audio spectrum analysis (basically, listening to a machine and tell if it is properly calibrated).
I will record the sound it makes with a microphone (it sounds differently if it is calibrated correctly than if it is not), and then want to look at the audio spectrum, with plans to automatically tell if a machine is set up correctly (currently, a human operator listens to the machine and does this job manually).
As a first step, this does not need to be real time, i.e., I will just make recordings of the machine (once set up correctly, once not), and compare the audio spectra.
My question is: Aside from the microphone, do I need a hardware spectrum analyzer, or does PC software suffice for this (FFT can of course be done on a computer too...). Particularly, because for a start, I do not need real-time analysis.
I am mainly asking because it seems that spectrum analysers cost quite a lot, and I don't want to purchase such a device if I don't actually need it.