Mics for use with ETF

Hi, can someone answer this for me please? Will any omni-directional mic give me precise enough results to be used in calculations or should I get something like the ETF test microphone? For example can I use a $30 Radio Shack omni-directional and get good enough results? Will single channel mode give me very different results from dual channel mode?

The cheapest mics I could use are the Behringer ECM-8000 and the Nady CM-100. It's pretty easy to make an omni with a flat response so long as it doesn't have to sound good. Both of these mics are perfect examples of that. If you have a nice soundcard, single channel mode will do just fine for general room measurements.

Thanks David, I think I will give the Radio Shack mic a try then. This is probably the only time I will need it and I just want to get a general idea of my problem frequencies.

David, If I would spend double or triple the price of a Behringer ECM-8000, what should I buy? Option 1: 2 Behringer ECM-8000 for stereo measurement Option 2: 1 of the other higher quality measurement mics If the answer is option 2, which one would you choose? - DBX DRIVERACK RTA-M - BEYERDYNAMIC MM1 - AUDIX TR 40 greez Roman

If all you're doing is measuring your control room with the mic, there's no reason to spend more than the cost of a Behringer or Nady. If you truly need more accuracy in the high end (all these mics are extremely accurate in the low end), better signal to noise ratio, or you want to be able to record music with the mics, then spending more makes sense.

David, Thanx for your quick reply, just ordered the behringer. Greez Roman