there is also SW that dive you greater control than CD test discs (this may be what Jamscience is refering to to make discs). I have 2 packages, one freeware called "Multigen" is a frequency generator that generates simply sine waves - it has continuously variable frequency. It also allows more complex harmonics contruction. The other is AQT (Audio Quick Test) - it's more sophisticated and costs $. The entry version is $30. I'm only a user of these, not afilaited with either company. I have them loaded on a laptop that I connect to a pre-in for testing in room setup. I us the RS meter for amplitude measurements, but as has been said, this is highly imprecise. Finally, Jamscience's suggestion to burn a cd is a great idea for more quick testing. It's much easier to load up a cd, than to connect up a laptop, boot up, etc, if all you want to do is run a quick scan.