Test microphone positions

Hi guys! Just a few questions about acoustic testing; hopefully one of you will be able to help, or point me in the right direction to knowledge! Just comming up to testing my LIVE room, and as well as using the room mode calculators etc mentioned on this site, I intend to test my room using a flat response microphone (or near - ive got one of them behringer ECM8000 jobbies) and some test frequencies........ Which brings me on to my first question: is using pink noise or sweeping-frequency tones the best bet? - I guess that both will enable modes in a room to be identified (with correct mic position(?) - question 2 (to follow)), but which does the job best? Am I right to think that single tones will highlight modes at those frequencies which may not be present when a complex sound (pink noise) is played (which I presume will cause additional cancellation/re-inforcement)?? Question 2 - where do I put my microphone??? I understand that different modes will occur in different places in the room, so do I have to run a test with my microphone in every position to find them all?? Obviously in reality such a method is impractical, but are there certain points to record in? Also, I spoke to a semi (self confessed) expert, who suggested ponting my test microphone at a corner is the best bet? Is that right? I luckily have at my disposal an omni directional speaker, which I believe is ideal for this type of testing. Am I right to think that positioning this in the centre of my room when blasting out my test sounds (whatever they will be) will be the right way of playing my sound? Ive tried to look into this everywhere on the net and I still cant fully answer my questions - im sure ive missed something though, and if the answers have been staring my in the face all this time on this site I appologise in advance. Thanks. John

Posted this in the wrong place - its been re-posted in the acoustics forum