Set-Up Tips

Thank you for the useful spreadsheet. Together with my old Tek 314, I hope not to purchase a $400 Fozgometer.

What a hoot! I just bought a Fozgometer about a week ago, specifically because the 'scope method is a pain. I can tell you it is fast and easy, the Fozgometer, that is, so I don't regret my purchase. I have an old HP 'scope, so it isn't light weight.

Can this be used with a multimeter? Would you connect meter to the preamp output or directly to the tonearm cable? (Assuming low output MC).
Thanks!

i much prefer to agree with Marc Gomez's recommendation that it is better to adjust the azimuth optically in relation to the surface of the turntable platter with microscopic inspection. If one adjusts the azimuth with a test record and uses an oscilloscope for this purpose, one can set an optimal adjustment in relation to this one record only. Records, however, turn out to be the complete opposite of high-precision sound carriers with the smallest manufacturing tolerances. If, when cutting such a record, even one mechanical parameter deviates slightly from the optimum, this error is then transferred to the azimuth setting. And how do you want to check how well the test record was made? If, on the other hand, the azimuth is set with enormous optical magnification on the flat surface of the platter, one can never be sure how perfectly the grooves of records are aligned with it, but one can be very sure that the needle, no matter how crookedly it may be installed in the cartridge, is perfectly aligned at right angles in relation to the surface on which the records lie. This would be the one advantage. Another advantage is that you take the measurement of this type when the tonearm is at rest. Measuring this value using a test record and oscilloscope, on the other hand, adds other mechanical influences that come from the operation of the tonearm, and can affect a very accurate measurement. For example, antiskating can never be perfectly adjusted because of the constantly changing groove modulation and will influence the measurement results. In addition, only very few tonearms play without interference. I performed this procedure on my system with a camera and an extremely magnifying macro lens. On the computer, i could then measure the needle angle and correct it on the tonearm. Just like you do this with SRA Setting. If the azimuth deviates even a microscopic amount from the perpendicularity, the spatial sound, three-dimensionality and detail resolution immediately collapse. With this variant of setting the azimuth, i have achieved results that surpass anything and the sound appears to be the optimum. If you don't have a macro lens or microscope, a DSLR with a macro reversing ring ($40 +/-) and a standard lens will do the job very good.

Firstly, I have yet to see a detailed explanation or video - Mr Fremer pls do a video - of how this is ACTUALLY done with a scope.

What I do is:
Use the Analogue Productions LP left-only and right-only 1KHz signal tracks
1- Using the left-only track, I look at the right channel signal on the scope and take a snapshot (with my phone of the snap feature in my scope) of what I see
2- I reverse the leads going into my phono pre (left to right and right to left) and play the right-only signal and take a snapshot of the scope again. I reverse the phono leads from the turntable because I want to use the same channel for both measurements so that the gain is exactly the same.
3- Comparing the two I determine if there's an adjustment needed.
4- If I need an adjustment I shim the cart mount with folded aluminum foil - 10 folds. I have an SME V which does not allow for adjustment so I have to resort to this method - however, the precision of this method beats any screw method as none of those generally have a calibration scale.
5- With just two measurements - even if you went to the wrong side - you can interpolate to the right number of aluminum foil folds to get the exact azimuth.

One word about zenith: this is also not adjustable in the SME V. However, there's enough play in the screws that a small zenith adjustment can be made. The oscilloscope process is to read both channels of the output into two scope channels and find the zenith position that cancels the signal the most. You cannot generally do this on the phono pre if it is not fully balanced so you need to do the cancellation math on the scope.

One more comment about any of these: If your cartridge requires more than just a slight adjustment, your cart is fecked up and needs replacement. If any more than a slight adjustment is needed, you can imagine that aligning the stylus will cause a misalignment of the armature, so really get the piece of junk fixed.

I have to confess that discussions like this make me dizzy. I think few here would disagree that the ultimate intention of this hobby is to derive pleasure from playing music. There are many ways to go about this. By in large, those commenting here seem very concerned with the minutiae, the mechanical aspects of vinyl playback, VTA, SRA, azimuth, etc. I’m not being dismissive when I say “”Good for them!” Each to his own!

When I think of my dad in the 1950s and 60s listening to music on his basement console and homemade speakers, it seemed to me, he enjoyed listening immensely. He had never heard of VTA, SRA.
azimuth. But he enjoyed the music regardless. How does one measure pleasure? Did he enjoy the experience less because his system was not as sophisticated as many of our overengineered turntables today? Or because he did not have footers for his cables or cables that cost thousands of dollars a foot? I would argue he enjoyed it more because he wasn't obsessed with GETTING EVERYTHING RIGHT, with achieving perfection. He just listened to the music and at times seemed transfixed. Who could blame him for that?

This question concerns SME IV and V tonearms, How can I adjust azimuth, rake error and zenith error or are they not adjustable on those arms? I've been using my modified tonearms incorrectly per this discussion for 33 yeas and will never achieve great sound. However, none of my friends who own similar high(er) end analog setups ($5K to my $20+K, some with unipivots) do ajustments for those parameters and we all use line contact (one micro-ridge) stylii. We are meticulous in adjusting VTA, VTF and anti-skate. Sure, back in the 50s and 60s the choices were conical and elliptical, the former having few requirements. I guess we all have to suffer with good but not great sound, huh?

Thank you for all the constructive suggestions.
First, I must repeat what I wrote at the beginning of my first comment.
I followed up on the following quote from Positive Feedback:

https://positive-feedback.com/reviews/hardware-reviews/swedish-analog-te...

Swedish Analog Technology (SAT) LM-12 Tonearm: Analog Playback Meets Rocket Science
07-01-2019 | By Myles B. Astor | Issue 104

From the second to last paragraph of the report at the very bottom of the page, here is what I found:

“Then it's onto setting cartridge azimuth. There are a number of different ways to set azimuth including the Fozgometer (that uses crosstalk) or software-based methods such as those from Feickert (that uses either crosstalk or phase) or the newer AnalogMagik (that uses distortion measurements). Marc, however, suggests (and recommends) setting azimuth optically for maximum performance and tracking accuracy.”

Yes, it is the Marc Gomez who makes the SAT tonearms.
Please do not misunderstand me. It is not about a religious war or to proselytize only my conviction. In the end, everything should only lead to the fact that we can extract the maximum from the grooves. And as we all know, there are many roads that lead to Rome.

Of course, it is not only a matter of the diamond's shaft being straight, but also of the lateral flanks of the needle, viewed from the front, both having exactly the same dimensions, i.e. the length of the angled surfaces in contact with the groove flanks, and both having exactly the same angle in relation to a straight surface. Thus, no method can be used to make optical checks of the needle flanks in relation to the groove flanks of the records during operation.
Of course, you are absolutely right that this is not all, however.
Because it also depends on the relationship between these geometries and the coils positioned on the cantilever at the rear. If the needle is at a right angle and the two angled flanks seen from the front have exactly the same dimensions and are formed at exactly the same angle, this does not mean that the needle is in exactly the same relationship to the coils. It is also very difficult to measure or visualize this. From therefore the point goes to you and I will use for comparison a measurement that you recommend and can but ultimately then evaluate the differences only sonically.

Due to the enormous problems in the production of these micromechanical systems, there are constantly inaccuracies even in cartridges for many thousands of dollars. From therefore I will compare the purely optical adjustment once with that of an oscilloscope and a test record.

But there is another background. With the method of an oscilloscope, it could well be that they get best measures for both channels. If you then use the optical method, however, it could very well be that the two edges that are in contact with the grooves are then skewed.
This misalignment then inevitably leads to asymmetrical wear of the needle. So it now suggests itself to us that no matter what we do, there are always imperfections we have to live with, both in the geometries of the products and in the adjustments we make. So far, my experience with the optical method has always been very clear audible. Nevertheless, I will also use your method, and I am already very curious about the differences.

Thank you very much for your detailed recommendations.

Thanks for sharing this, will be very helpful.

I was wondering if anyone can help me with something? When I've tried to set my azimuth before, I've used a Behringer audio interface and oscilloscope software. However, with the phono stage (Trichord Dino) at the normal and correct settings for my cart (Hana SL), when I measure a 1khz sine wave it's clipped, even with the gain set on the interface to the minimum. If I lower the phono stage gain so the waveform is not clipping, is it fine to then calculate the crosstalk as normal? Or should the settings on the phono stage be set correctly for the cart?

Also, when taking the voltage measurements for this software, should I be looking at RMS voltage or peak-to-peak?

Thanks in advance!

If the waveform is clipping you won't get good data. Confused by your comment "even with the gain set on the interface to the minimum" and then later you suggest later than you can lower the gain further. If you can lower it, do it until you no longer see clipping. If you see clipping in one channel only get a WallySkater to figure out what is going on with that tonearm.

RMS is what you are looking for

Why convert volts to dB at all? Isn't raw voltage ratio much more sensitive to changes than its logarithm?

Can someone help out a neophyte with this? What voltage readings does one use? My software 'scope (Soundcard Scope) gives peak-to-peak, in "m" (which I can only assume is millivolts) and effective voltage (which I take it is the same as RMS?), also in "m." Thanks very much, N.