Dear Rockitman,
If you want to use your own tools to adjust for azimuth, I do not think it is as simple as Dertonearm implies. You also need a pure test tone on an LP (usually 1kHz will suffice, but if you are fanatical you could use more than one frequency, and ideally a notch filter to get rid of spurious noise above and below the test frequency. This is why Fozgometer sells. You zero out both channels for equal gain. Then you play a test signal on one channel only. Measure voltage. Call that "0db". Now play the same test signal into the same channel and measure voltage that appears on the opposite channel. That will be a much smaller voltage, hopefully. Convert that into db, which will be a negative number, like -20db or lower. This is "crosstalk". Do the same in reverse. You will have two values of crosstalk in terms of negative db. Now play with azimuth and see how the values change. Some like to adjust for equal crosstalk in both channels. Some others like to adjust for lowest possible crosstalk, regardless of whether the numbers are equal in value. (I have always observed that I can get less crosstalk if I settle for unequal crosstalk. For example, I might be able to get -25db in both channels at 1 kHz. But if I just shoot for least crosstalk, I might get two values of say -28db and -30db. Life is funny that way.)
