2. analog
  3. 156988-20132

Cartridge azimuth adjustment using a voltmeter and a test lp

Hello all,
I know that azimuth adjustment comes up often as do the various methods to get it right- or close to right.  I have been doing a lot of reading on the subject and I realize that using a voltmeter with a test lp has its flaws vs using other techniques that use sophisticated instruments and magnification to physically determine if the stylus is perpendicular to the record surface.  Nonetheless I would like try using a voltmeter to see how this compares to how I have the cartridge currently set up- but I have a question:
The generally accepted method is to use the amplifier output terminal to measure the voltage output of the test lp- but would it be a problem to measure the voltage at the speaker terminals?  Even with the interaction of the speaker cables the voltage variation at the amp terminal vs the speaker terminal should be very minor.  But I have seen in some posts that some suggest it is better (or necessary) to measure at the amp terminals.  Why?
Arguably, if cable and other circuit interference were such an issue then it would make more sense to measure the voltage at the tonearm terminal for the phono cables, assuming the voltmeter has the necessary range to measure such a low voltage output.

The reason I ask is that reaching behind my amps, pass labs xa60.5 mono's, would be a real pain and if the measurement has to be taken at the amp output I would like to understand why.

Many thanks for your advice.

System: Thiel 3.7's, or Magico S1 mk1,  Pass Labs xa60.5 mono's, Vinnie Rossi LIO preamp (slagle AVC passive mode) or Prima Luna Dialogue Premium preamp, Moon 280 Dac, PS Audio Stellar phono, VPI Aries 1 turntable/JMW 10 tonearm with Lyra Delos cartridge, Nordost Heimdall 2 cabling.
pgastone
Ag insider logo xs@2x
cleeds
5,960 posts
 
stringreen
mijostyn.....I suspect you are way off. Most mirrors are silvered in the back and therefore you’ll have a great deal of error with the stylus resting on the glass with a few mm to the silver.
Oh no, not at all. The distance between the silver and the stylus magnifies any alignment error, simplifying adjustment. If you use a gauge inscribed with a reference line - such as the original Wallytractor gauges - you can align the reference line with its reflection. That eliminates any parallax error and if the reference line then evenly bisects the reflection of the cantilever, you have achieved something very close to perfect tangency at the null point. That is exactly the advantage of using a mirrored gauge.
mrubey
36 posts
 
I find that all of the cartridge adjustments need to be optimized for the cartridge to truly express its potential. This is no less true of azimuth than any other parameter, including antiskate. I thought my cartridge was doing great when it was visually vertical. Then I found the by ear method using a mono record. Using that I found a spot that took my cartridge to the next level of presence and transparency. The reason a mono record is used is that it provides a more stable centralized point of focus in adjusting a stereo cartridge by ear. Using azimuth adustment, you will be able to move the center image to the right and left by moving the adjustment back and forth. When the mono center image of the stereo cartridge is dead center. Then in very subtle movements within that dead center area of adjustment there is a point of maximal focus, vividness and presence. This is the azimuth sweet spot. Peter Lederman points out two things regarding azimuth. First that if you have a cartridge with extraordinarily high separation, the separation is probably not perfectly electrically symmetrical and a meter will not give you perfect azimuth. The second thing is that high level Soundsmith cartridges are extremely sensitive to azimuth and that it’s worth it to take the time to find the sweet spot. In my experience this extrapolates to other correctly constructed cartridges.

sdrsdrsdr
196 posts
 
@melm    When you mention horizontal alignment are you referring to zenith?

Zenith and azimuth can both influence the readings on the fozgometer. Other than setting these two with tools and eye sight, can  you tell with fozgometer or other voltage measuring  devises between zenith and azimuth? I’ve never been certain about these two settings.
lewm
13,120 posts
 
mrubey, Most cognoscenti (and I don't count myself as one) would say that using a mono LP is not the way to adjust azimuth.  Centering the image is mostly the result of achieving equal channel balance, and the goal of azimuth adjustment is to minimize crosstalk. While azimuth does also affect channel balance, it does not do so by much, and changing azimuth is not the optimal way to ameliorate differences in output, one channel vs the other.  Conversely, using a mono LP to center the image is not necessarily going to get you to minimal crosstalk.
mrubey
36 posts
 
I’m just saying it works. And it works brilliantly. Its not my technique. It came from Durand tonearms who build the Talea. I believe that finding that point of optimal performance using this method is another way of achieving minimal crosstalk.
But my primary task isn’t to............I just flashed on that we are using different criteria of basic assumptions. My understanding is that correct azimuth means that each side of the stylus is in equal and maximal contact with each side of the groove. Reading crosstalk values using a meter is one method of defining misalignment then adjusting to achieve this.
However; according to Peter Lederman who is building a Paua for me in the current timeframe. Using a meter to find optimum azimuth often doesn’t work on his cartridges due to extremely elevated and often unequal separation values. Consequently, if I were to use a meter and adjust azimuth settings accordingly I may well misalign the stylus in the groove. A slight deviation falls under a miss being as good as a mile. My previous, now traded in cartridge was a Grado Reference 2. When I found and implemented this by-ear-azimuth technique the performance of the cartridge elevated amazingly. The difference in adjustment was a hairs breadth.

I think Peter Lederman is a rare genius.
I suggest anyone interested in the stylus dance with the groove watch the two seminars of his in ’17 and ’18 at RMAF on YouTube.




More to discover