Hi Guys,
I had another chat with Wally. Using pink noise as a test tone for setting azimuth will not work. Pink noise is random. Thus, the volume constantly changes and you will not be able to get a constant reading on your voltmeter. Though if you had a sophisticated meter that could average the reading over many seconds, then it might be possible to use pink noise.
Wally was also of the opinion that it is more important to have the azimuth correct at 1000Hz, rather than 400Hz or 5000Hz. This is because the midrange is where human hearing is most sensitive. Yes, you can measure at 400Hz, 1000 Hz and 5000 Hz. That will create a range of settings for you. However, you will need to determine by ear where in that range of settings is the best setting. Wallys belief is that the best setting in that range determined by ear will be very near the optimal 1000Hz setting determined with a voltmeter and test tones.
Wally also mentioned that it is very difficult to set azimuth by visually aligning the cartridge body. Tilting the cartridge body by .25 degrees changes crosstalk by 2dB and changes the relative heights of the left and right sides of a 20mm wide cartridge by .1mm. Tilting by .4 degrees makes a 3dB change in crosstalk and a .15mm change in relative height, left to right. Tilting by 1.0 degree changes crosstalk by 6dB and changes relative heights by .333mm. So a very small change in tilt, visually indiscernible, can have an clearly audible effect on sound.
More food for thought.
Best Regards,
Roger