Setting Azimuth


I've attempted to set/fine tune the azimuth on a Graham 2.2 using the KAB device made to test azimuth (and a mono LP). I have not been able to achieve complete silence -- which is my understanding of what I am aiming for with the KAB device. No matter how much I tweaked the azimuth adjustment on the arm, I always had some sound coming through. The volume seemed to vary with location on the LP -- i.e. between the outer tracks and the inner tracks. I then swithched to using a headshell level -- got the arm level -- and still heard sound through the KAB. I have the anti-skating force set as low as the arm allows. My questions: (1) is what I'm experiencing a result of the anti-skating setting? (2) what exactly am I supposed to hear when setting azimuth using a channel cancelling device like the KAB (3) what else might I being doing wrong. Thanks for your help.
vtl
Adjust my listening.

Make small sdjustments and listen to the change. That is what I did on my Basis vector tonearm with excellent results.

Getting the Azimuth dialed in is very improtant. The improvement on my arm was amazing.

Johnny
Dear VTL,
Herman & 42659 are correct. However, although proper azimuth is critical for any cartridge, it is particularly critical for smaller stylus shapes. Listed by increasing sensitivity are conical, then elliptical, then the rest. This is why some cartridges you can get close and it is fine while with others azimuth needs to be carefully aligned and tweaked in. Since you do not mention which cartridge you are using on the Graham 2.2 tonearm it is difficult for me to know just how critical the azimuth adjustment is in your particular case.

Perhaps "Narrod" is correct - I dunno. However you should use a cartridge analyzer or an oscilloscope for optimum results along with a proper test record (left channel tones on one side and right channel tones on the other side - LONDON & Decca made these). When the cartridge output levels match from each side of the LP the azimuth is correct. The "vinyl elders" were no fools and up until 25 years ago or so this is why people would take their TTs to be professionally set-up to optimize performance.

If you can't do it yourself, then have someone help you that can or has the proper test equipment (a.k.a. "take it to someone for proper set-up). Some folks claim they can adjust azimuth "by ear" but I never could, I need test instruments - especially for higher priced, finer stylus, cartridges. Please understand that mechanical techniques can get you close but only proper electrical measurement can reveal the actual signal levels. And after all, THAT is what we are listening to so it needs to be correct "at the source".

ANOTHER TIP: One thing that will drive you NUTS if it is not correct is Zenith. This has huge interplay with azimuth. When setting up your cartridge do NOT just align the front of the body with the perpendicular line on the tool. The cantilever MUST follow the line in the alignment/overhang tool. Relying on the "trueness" of the cartridge body is incorrect as cartridge manufacturers rarely have mass produced cartridges come out "true". The Feickert and MoFi tools really help with this as the "lines" are easy to sight and the cantilever being "off" or "cocked" is easy to see.

Lastly, good, used, older, small, O-scopes have REALLY come down in cost on eBay and elsewhere. Even NEW proper probes are affordable now. I'm simply stunned how many audiophiles will have costly tweaks and mega-buck cartridges for vinyl playback (not to mention "brilliant pebbles"!) and do not own an O-scope or a cartridge analyzer and proper test LPs. Not a criticism just an observation. Since audio frequencies are "easy" for any O-scope (they are ranked on frequency range so a 10 MHZ scope is far obsolete now for lots of things but FINE for audio work!) they are inexpensive and easy to use.
Another similar method is to just play some Mono records and adjust azimuth until the image is properly centered in your soundstage.
Herman is correct. Perfect silence using the KAB device would require a cartridge (and alignment) capable of ZERO db of crosstalk. A cartridge that perfect will probably never exist. It certainly doesn't exist today.

I also agree with 42659 and Aoliviero. Depending on your system (and ears) you can get very close to optimal azimuth by listening. Proper azimuth reduces crosstalk. Reduced crosstalk improves imaging, so listen for the tightest, best defined images. Higher pitched vocals or instruments are probably best, since our hearing localizes higher frequencies better than lower frequencies.

Measurement, as suggested by Jhendrixfan, certainly works and will produce the best results possible with any given cartridge. But one can get just about as close by ear, at least IME. I've done it both ways. They both work. Use whichever one floats your boat!

Doug