I've used many different softwares, fuzz measure is quite handy for fast measurements which gives a lot of info but not useful to work in real time which you may want to tweak eq and acoustic traps for placement or tuning. I just use one speaker at a time, facing away from the mic, in a corner of a room, the mic placed at the center of the room, to capture a general idea of what's going on. For the mic I have an ECM8000 than is really handy for all this measurements than don't need laboratory grade equipment, any smallish diaphragm omnidirectional condenser will work just fine as long as it doesn't have a really bad freq response but even quite cheap electret capsules are good enough for this application.
Usually the first thing is to bring RT times to a confortable amount, depends on taste and room size, by the use of absorption, I wouldn't care too much about traps on the first step.
Then you need some way of getting a waterfall which will show you the problematic frequencies on your room, at the low end, the exact frequency to call it low end will depend on the room size, this is like a more detailed RT analysis. You should attack each long ringing shown on the waterfall independently with traps of various types, if you have a few close to each other a wider band trap will work. Once you have solved those problems you could go for the next cryptical step which is placing the monitors and the listening position.
The one thing to have in mind is called SBIR (speaker boundary interference response) which will cause peaks and dips pretty much independent of the room size but related with the positioning of the speakers themselves, something similar with the placement of the listening position. There was a good software to work with all this (acoustic X, late 90's) and I haven't seen anything quite as handy since then, you would need a W98 or something like that to run it... I've written a little function in mathematica to play around with it, the idea is to get the smallest dip possible and don't care too much about peaks, since they can be attenuated by filters without much of a problem (other than phase shift but that's not a problem any more). Once I solved one really big problem just by shifting the x-over frequency by 1/3rd octave because as the placement is different you will have different problematic frequencies on the sub and the HF monitors, then usually some attenuation in the low end is almost always needed. At this step I usually align the phase as good as I can for the main listening position, cut the peaks and call it a day, as long as I don't end with big dips.
The "string analyzer" was other method which consist in attaching a string from the speaker to a mic stand at the listening position, the string should be variable in length, adding a few centimeters to the initial length will show the comb filter generating surfaces, usually the desk, mixer, etc. Then adding about 2m will show the surface which can cause image shifting, using a small mirror and a flashlight, this usually take two people, one pointing at the mirror with the light, the other placing the mirror in different surfaces which may be problematic pointed by the string analyzer, if the light is shown at the monitor position (or close enough) you should treat that surface, could be changing the position, angle or using some absorption so the reflections are attenuated or diffusion on it so the reflections are not specular (as the light with the mirror) and much smaller.
Then make a last measurement of all you can from where the monitors are to the listening position to see if everything ended up fine, then maybe a few other places just to be aware of the problems out of the listening position.
That should cover as quick as I can how I do this kind of things, it could be pretty quick or not, easy or not, depending on the room which you started off, where you want to get and the time you have to do so. A proper control room could have some diffusers for example but that's quite more involved and time consuming, since usually a custom made solution is what is needed to work at the proper freq you need them to and to work properly in the particular room you are treating. Also the measurement of that is quite hard to do and quite hard to see what you need or how better it is after the job is done. Is not imposible to measure or just better in subjective POV but much harder and a proper measurement of those parameters to find any specular reflections hitting the listening position would require equipment that's not so easily available or cheap.
JS
