Hi Chandliz, It is actually quite simplie, even if I did have to ask for assistance from my brother!
You dont need the Behringer unit to do this, so just put that to the side for now along with the test disc as the REW provides its own test signals.
You dont need the micropone either at this point but later on it can be used if you so desire, you know upgrading and all that.
Do you have a radio shack or other sound level meter? If so, that is used for its microphone capabilities as well as the SLP meter.
The first thing to do is download the REW software (for FREE, its for free, I love that!) current version is V4.11
The second thing you need to do is calibrate your sound card on your computer. You need a cable to go from the speaker or headphone out to the mic in, you are running a loop out and then back in to your computer to calibrate the soundcard. The software put out tones and then it runs back into the computer and compares the output to the input and corrects for any level problems on the soundcard.
Now you have the free software loaded and the sound card of your computer calibrated for the software. You need a cable from the speaker or headphone out of your computer and run it into an aux input of your preamp. So it is most likely a 1/8" jack to RCA cable.
You are almost ready to make a measurement but first you have to calibrate the Radioshack SPL meter. Again you need a 1/8"cable at the input of you computer mic in and a single RCA to the input of the Radioshack SPL meter. There are controls at the top where it says calibrate and run the test to obtain 75db reference level (or one close to that as you may need to adjust up or down depending on the the steps in your stepped attenuators if you have them such as I do.) You then need to mark the volume control position as every test is taken from the exact same level for obvious reasons.
Then run the test and post it here.
Bob
