Fozgometer


I've used this gizmo a few times before and think its a very valuable tool. I'm setting up a new cartridge, and nearing the end of a whole day job...anyway, I'm using the proper test record, yet, the meter doesn't work...I get a dull lights on the 2 red ones, although the middle power light works. Any suggestions?
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Lew, no, they do not imply that channel imbalances can be fixed by adjusting azimuth. However, the manual would be much more useful if it included information on how to deal with channel imbalances when adjusting azimuth for optimum channel separation (crosstalk). There are discussions on this topic at several forums but no clear answers as how to best handle it.

Regards,
Tom
Many years ago on Vinyl Asylum, two very knowledgeable guys wrote long treatises on azimuth. At least one of them was an advocate of adjusting for "least crosstalk", rather than "equal crosstalk" (into both channels). Along the way, both stated that one should not attempt to correct for inequality in gain between channels by adjusting azimuth. First of all, even the most extreme differences in azimuth make a very small difference in relative gain between channels. I tried it with my Triplanar and Signet Analyzer; a difference from about +15 degrees to -15 degrees off the 90 degree starting point made barely a 1 db difference in channel balance, and by the way music sounded awful at either extreme. And second, you can't have it both ways; correcting azimuth for crosstalk, as one should do, will not lead also to any significant correction in channel imbalance. So, I guess you're referring to how channel imbalance might contribute to errors in adjusting azimuth for crosstalk. (Yes?) To me, that is no problem if you reference the adjustment to a "0db" point with respect to the channel that is receiving the signal, as I noted above. Don't know about the Foz, but the Signet allows you to do this. You'll still have a channel imbalance, maybe, but crosstalk will be as low as you can get it. The point is that referencing both channels to 0db for the driven channel removes the inequality in gain from the equation, as much as is possible and IMO.
In a couple of years of adjusting azimuth on multiple cartridgess using the Wally Analog Shop tool, I don't remember ever seeing much change in output (ie, channel balance), but differences in crosstalk (ie, channel separation) were immense.

About 10 years ago I dropped the instrumentation after realizing that I can adjust by ear just about as accurately and far more quickly. As with the instruments, I've never heard a difference in channel balance when tweaking azimuth within reasonable limits (ie, within a degree or so from vertical), but changes in crosstalk from even the tiniest possible adjustment are readily audible.

YMMV, of course...
Dougdeacon,

Can you recommend a currently available test disc that facilitates the listening method? Interestingly enough many years ago I found that the listening method was easier, faster, and better than all the instrumentation just as you suggest. Back then I used a Shure test record that is no longer available. BTW, in those days, while in college, I worked in high end hifi retail and was the go to guy for setting up turntables. So I had a lot of practice.

Thanks,

Bill