Cartridge alignment channel balance measurements?


I'm curious as to how people go about measuring channel balance when adjusting your cartridge alignment? If you are performing measurements, what is your accuracy tolerances?
128x128Ag insider logo xs@2xjames1969
 
Start with the Cardas Frequency Sweep test record for $24 from Acoustics Sounds (or whomever), along with a Voltmeter, then ...

How to measure crosstalk
 
Be sure to read on down that thread on the importance of using a bandpass filter at 1kHz, or you won't get the desired results.
James1969,

When I adjusted azimuth with this method I used the Wally Analog Shop, same as Jtimothya. It works exactly as he described and you can DIY as he also described, subject to Dan_Ed's provision that you use a narrow bandpass filter centered on the frequency of the test tone. Without that, surface noise makes readings highly variable and difficult to interpret.

I actually haven't bothered with the Analag Shop for at least a couple of years. As the resolution of our system grew we learned to adjust azimuth by listening, just as accurately, faster and while playing music rather than test tones. Besides, our current cartridge, when properly azimuth-ed, produces crosstalk below the resolution of my multimeter. Using Wally's chart it's somewhere below 0.3db, which makes the whole rigamarole ineffective without investing in more sensitive equipment. It's easier to just play music and fiddle!

The thing to listen for is the tightest possible sonic images (from L to R). The narrower and better focused an instrument or vocalist sounds, the closer you are to minimal crosstalk. Intruments and vocalists with pure tones in the higher registers are best. Our hearing system is most sensitive to directional/spatial clues at higher frequencies.

BTW, I wouldn't say the measuring method isn't worth trying. You'll learn something, including how remarkably tiny adjustments to azimuth can have a measurable and audible influence. From your baseline starting position (which probably should be "stylus appears vertical while playing in the groove", not "headshell appears horizontal") changes of less than 1 degree will make a difference. Go very gently with this adjustment.

Best,
Doug
Very interesting.

Dan_ed, I have always wondered how to get around the surface noise issue, seems like surface noise alone adds quite a bit of 'variability' to the signal from what I have seen. A bandpass filter makes perfect sense. But I don't know how I would implement one, I will have to research that a little more.

Doug, I would agree on ultimately using your ears to make calibration adjustments. I have an over hang tool that came with my Technics turntable, I find the tool to adjust the needle relative to the over hang mark will put the cartridge in in the neighborhood of where it should be, but further adjustments by ear is far more precise.

Thank you both,
best,
James