Azimuth observations and importance


After adjusting azimuth with a Fozgometer loaned to me, the following is what I observed. Individually, these changes were subtle although noticeable. The combined effect however, was significant to the overall presentation.

Imaging improved.

Vocals became more focused, not as big and wide as before.

Instruments more detailed with greater air. Location is more precise.

Tighter bass versus the slightly lingering bass notes previously.

Better top to bottom detail and clarity.

I never realized how important correct azimuth adjustment is and this exercise was quite a learning experience for me. Thinking I was correctly adjusting azimuth by visually setting the headshell as level as possible was a reasonable but flawed attempt.

I have found at least two stylus issues that if present will affect azimuth and sound.

1) A straight cantilever that is twisted left or right changes the attitude of the diamond and its relationship to the groove. By twisted I mean the cantilever has rotated on its own axis. This one is very difficult to see without appropriate magnification.

2) A cantilever that is canted to the left or right a degree or more but is still straight, not bent. It points left or right probably because it was not centered correctly when the cantilever was installed. It also changes the attitude of the diamond.

What is probably basic and common knowledge to everyone here is something I have just been enlightened about after giving it very little thought. I am now convinced that accurate azimuth is a required step in the turntable set up process and I will be giving full attention to this part of the equation.

No more guesswork and eyeballing which I am embarrassed to say was the norm. Doug
128x128dougolsen
Using a multimeter without the high- and low-pass filters Lew mentioned will probably produce unreliable results. Surface noise from the unmodulated groove wall will be part of the signal. That will look like crosstalk to the meter. Scope users would filter for this of course.

The Wally Analog Shop is just a box containing filters around 1kHz, resistors to simulate a speaker load, speaker terminals as inputs and connections for a multimeter. It takes the output from your amp by plugging your speaker cables into it. That's less than ideal as Lew suggested, since you're measuring crosstalk for the entire amplification chain. OTOH, everybody has speaker cables so it works in every system. Further, a high level signal is easier for a meter to read. If I had to measure at my phono outputs the crosstalk from my best LOMC would be too small to measure or adjust accurately, at least at the resolution of my meter. Measuring at the amp outputs is simple and practical, if slightly "wiggly".

If we're going to fine tune by ear we're going to be adjusting for the crosstalk of the entire system anyway, so...

I guess my thinking was to balance my phono stage (uncommon for most I guess) so that when I do the Ultimate Test Record azimuth test, and won't have to worry that my phono stage is not introducing any error into the test.

I got a little confused; I am using the UTR and I forgot they have left/right channel only for azimuth. I'd like to set it up first with UTR, then listen to music (before/after):

Side 1
General Reference Level
This 1 kHz reference tone will allow you to establish a “base level” for all measurements.
Track 1 1Khz reference tone 7cm/s Mono, in phase (Lateral)
Basic reference for all measurements, adjust meter for maximum convenience (in the studio 0VU).
Adjust preamp channel balance for equal output.
Also used to check the offset angle of the photo cartridge; L&R signals should be exactly in phase as displayed on an oscilloscope.

Azimuth Adjustment
Track 2 1kHz reference level Left channel only
Measure Right channel output.
Track 3 1kHz reference level Right channel only
Measure Left channel output.
The object is to sit the stylus exactly perpendicular in the groove.
Twist cartridge about its radial axis until the measurements from Track 2 and Track 3 are equal or very close to equal for both channels.
Dear Doug, the OP asked how to do it with a multimeter. And that;s the question I tried to answer. Such devices do not have filters, true, but I was just trying to describe how one could do it with HIS tools, not the best way possible. Also, it is not far-fetched to assume that surface noise in the unmodulated groove wall would be about the same for the two bands on the test LP needed to make the determination and would hence cancel each other out, give or take a db here or there. The result would be a falsely high idea of the amount of crosstalk but it would still permit adjustment to obtain minima.

In reality, to adjust azimuth I have only ever used my Signet Cartridge Analyzer and my scope occasionally plugged into it. (It has a scope output.) I am not really familiar with these new fangled devices made by Wally, Dr. Feickert, etc. Do they utilize the amplifier outputs? Do you personally do it that way, notwithstanding that you do it by ear as well? After all the brouhaha around azimuth here and on the Grandezza thread, it is interesting for me to learn how those who have the luxury of azimuth adjustment actually do the adjusting.
Agreed, Lew, it can certainly be done without filters. It's just alot easier with them, since the output readings don't jump around so much.

I answered your followup questions in my preceding posts (though only for myself, obviously).