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Azimuth&Bias on HIFI test record

I bought a used Grado cartridge on the 'Gon. When I go to set it up, everythings runing smoothly VTA, tracking force, alignment. I then listen to the HiFi test record to test azimuth and bias. Concerning azimuth, the text suggests that the test tone should disappear, when the amplifier is switched to mono, because the signals will cancel each other out. Now my question, should there be dead silence or just a reduction in the test tone? On my set-up, when I push the mono button the tone is greatly deminished but, not completely gone. Concerning bias, on the test record they have you listen to a test tone. Supposedly you adjust your bias/anti-skate to smooth out the high frequency test tone. On my system the tone seems to modulate. Do I increase the bias until the tone stops modulating? Would like any advice from those that have experience with using test records. The Grado Platinum is mounted on a RB300 which is attached to a P3. So what's the scoop Analog elders?
colitas

Showing 1 response by 4yanx

4yanx
1,576 posts
 
An old fashioned way to check azimuth is to scratch or use a marker to draw a line perpendicular to the bottom of a small pocket mirror. Then, IF your platter is level, slide the mirror up near the cartridge and view from the back side. If the cartridge has a perpendicular side edge it should line up with (be equidistant to) the scribed line. If the cartridge isn’t “square” it’s up to the eyeball for a manual setting, though even some of those have a vertical line on the front of the cartridge body. For anti-skate, I go with my ears, but Lugnut is correct that the only perfectly “accurate” way is to use a ‘scope. Oh, and I have seen it set using a ‘scope and having it subsequently fail the HiFi test record gauntlet!

Doug, did you mean azimuth test and not bias test with respect to the HiFi record when you say "Colitas, The HFN bias test tone varies from inaudible (good) to a steady "buzz" (needs adjustment) to a rough or warbly buzz (dangerously near mistracking)."?

My understanding is that there should ideally be no tone using a mono signal when doing the azimuth test. For the bias test, there should be a rock-steady tone and any "buzzing" indicates improper bias. If it is supposed to be silent, I can't get any of my cartridges past the first bias track! Ha!

Maybe we are mixing terms here. I just wouldn't want anyone that is using the test record for the first time to be confused.
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