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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
dougolsen

Showing 6 responses by dougdeacon

dougdeacon
3,338 posts
 
Doug,

Congratulations on advancing to "adjusting by listening", and on learning to hear the difference azimuth adjustment makes.

Like Teres I used to use electronic equipment to adjust azimuth. After sessions with several cartridges I realized I could adjust just as accurately while listening to music, not to mention faster and with less fuss. You described EXACTLY what to listen for, IME.

Good that you discovered levelling the headshell doesn't help much. No one plays grooves with a headshell, we play them with a stylus and few styli are vertical to the necessary degree of accuracy. Levelling the headshell's usually a time-wasting distraction. Roughing in by eye is best done by making the stylus look vertical with a mirror and magnifier. After that the fine tuning is by ear and the headshell ends up wherever it ends up.

VTF, VTA/SRA and antiskating are also all best adjusted by listening to music. The more practiced we get the fewer measurements and test records we need.

Good post,
Doug

P.S. Hiho is correct. I described his observation by analogy many years ago on VA. Azimuth changes with vertical arm angle on any tonearm with an offset headshell. It's unavoidable.
dougdeacon
3,338 posts
 
Azimuth adjustment is not about achieving balanced output between channels, nor is it correct to alter preamp channel balance before adjusting it. Preamp channel balance should be set wherever you normally listen to achieve sonic balance in your listening room.

Unless I misunderstand your post, you may be starting from a false assumption.

dougdeacon
3,338 posts
 
So, do we listen in a wiggly world or do we use an objective test? Well, both... which may lead us to the enlightened state Lew mentioned.

Thom makes a valid point: having an objective standard to navigate through the wiggliness can indeed help train our ears.

My Wally Analog Shop (which measures crosstalk at 1kHz) did that. After 2 hours I got crosstalk optimized and played some music. The improvements were clear, quite as the OP described. This objective test trained my ears to listen through the wiggles.

After that, when changing cartridges I'd adjust by listening first, then confirm with the Wally. Having learned what to listen for, my by-ear settings became acceptably reliable and the Wally a waste of time; but it wasn't entirely so in the beginning.

Today, my reference cartridge produces so little crosstalk that the Wally can barely measure it. Using it would largely be a waste of time.

As Lew said, it's too late for most of us - but perhaps we can protect the newbies, if only by providing an object lesson.
dougdeacon
3,338 posts
 
Agree about the ease of the Talea's azimuth adjustment. Perhaps even more important, it doesn't compromise the rigidity of the armwand in any way. I'm looking forward to your lengthier impressions. We only had the protoype for a day and were VERY impressed. It beat the cr** out of our present tonearm.

The proper tone to optimize is obvious - use the one you hear best! For crosstalk, consider that the ear determines the directionality and distance of sounds at mostly upper-mid to high frequencies, so that's what we should listen for. Trying to assess the direction or image size of a bass drum or tuba is much harder than doing the same for a trumpet, bell or soprano.

Bells are especially good for this because they have a tendency to ring (heh!) if not reproduced very accurately. Any lack of clarity will be audible as distorted phase response, as mentioned by Essentialaudio. Paul and I have a few oddball LP's (okay, just stop thinking that!) with natural percussion instruments in the upper register. They're excellent for dialing in azimuth, provided you enjoy 12th C. Andalusian dance music.

dougdeacon
3,338 posts
 
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...

dougdeacon
3,338 posts
 
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).
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