HiFi News Test Record Azimuth

I recently set up azimuth on a new cartridge with a VTA/Azimuth block - output was unbalanced. Then used a Fozgometer and got equal output but no magic. Then an o-scope and found 75/150 mv crosstalk. Adjusted it to 65/80 mv. Slightly unbalanced output but Glorious sound. Lesson?  Measure the right thing and azimuth matters a lot.

If you are going to adjust azimuth "visually" (Chakster), then you really ought not to have a tonearm with azimuth adjustment capability, because in most tonearms, the default position of the headshell will already give you 90 degrees of azimuth... 

-On many tonearms without azimuth adjustment detachable headshell can be rotated a a bit in tonearm's bayonet. Correction always needed. 

-There are also headshells with azimuth adjustment. 

-There are also tonearms like Reed 3p with azimuth on the fly. 

But I adjust visually anyway (looking at the cartridge body and cantilever), I have the same Hi-Fi News Test LP.

  

Wlutke, just want to make the point that azimuth adjustment is not done to correct channel imbalance; it’s done to minimize crosstalk. Adjusting azimuth does have a small effect on balance but the resulting angle required to produce a small change in balance will be ridiculously to one side or the other of 90 degrees, thus endangering the stylus and the LP if used that way for any length of time, and it will be way off the angle for optimal crosstalk.

Adjusting azimuth affects crosstalk and relative phase of the two channels.

People can accept some level of crosstalk, particularly from speakers since you're hearing each speaker with both ears, but many cartridges (particularly less expensive ones) may have crosstalk in the -20dB range which isn't great. Getting crosstalk to at least -30dB is better. A digital system will usually have crosstalk better than -80dB across the entire frequency response. And I've read that -40dB is about the threshold at which people don't really care much or notice anymore. (Not sure how correct that number is.)

But more egregious phase differences can really mess up the sound. If you imagine a singer but their voice is coming out of your left and right speakers are slightly different times, it will sound really off and bad. And that is what will happen with all of the instruments.

That being said, you need to correct azimuth and phase electrically or using software. The actual physical location that needs to be calibrated is inside the cartridge, where the magnet and coils are, and their alignment is not perfect with the cantilever. Small 0.25° of change in the azimuth make a difference in the measured crosstalk and phase. But that's a very difficult angle of change to try and measure by sight. And every cartridge's internal alignment is slightly different, even of the same make and model.

This is why paying for a professional calibration can be worth it. You can of course learn how to do it yourself and purchase the necessary tools and/of software. Alternatively, don't worry about it too much and just enjoy your music if it already sounds good to you.

That's not it. Everyone's missing it. The problem is there are at least three different aspects, and while yes they all matter there really is no way of aligning them all- unless it was done right at the factory.

From the ground up we have the azimuth of the stylus. This affects the stylus ability to accurately trace the groove. Then there is the azimuth of the generator. This can be MM, MC or MI, doesn't matter from the point of view of azimuth they are all the same and this definitely affects crosstalk. This is the one we are adjusting with test records.

Then there is the azimuth of the cartridge body, which is what we all see and know. We trust that the manufacturer built all this stuff in alignment, that the generator is not twisted within the cartridge body, that the stylus is not cockeyed on the cantilever. 

If they did then we can simply eyeball azimuth and be done. But if not then we get to play around with test record after test record, and can easily spend a small fortune in time and money on all the various ways of trying to second guess whether or not the dang thing was made the way it looks like it was made!

Maybe with a cheap cartridge that is a viable question. But cheap carts go on cheap arms, and they tend to not have a lot of adjustments. VTA is far more important, and look how few have VTA on the fly. By the time you get into the expensive arms and cartridges that have azimuth adjustment, well if you don't trust your mega buck cart to be built right why'd you buy it in the first place? So the whole thing is whack.

Finally, I notice we have a recent thread where the poor new guy was turned off vinyl, and why? Because of all the navel-gazers obsessed with every micro minutia theory who kept telling him how impossible it is to play a record. It is not impossible. It is easy. Just go back and read the second sentence of my first post again and relax and enjoy the music.