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When setting azimuth on my VPI Classic with Denon DL-S1, I get a very good crosstalk measurement of 30dB (using the Fremer method and a voltmeter) but the arm looks tilted (see photo). I was wondering if any of the inmates had any direct experience with this or would like to offer me their opinion. Should I trust the measurement and not worry about the tilted arm? I probably should also say that the cantilever on this cartridge is slightly off axis.
you're seeing an exactly equal amount of crosstalk (-30db) in both channels. Is that the case?
Other guys mentioned, and you already know, that the azimuth adjusted for best crosstalk numbers electronically may result in the azimuth angle off 90 degrees, as in your photo. Someone else noted that this can be due to an imperfect mounting of the stylus or a bent cantilever; it can also be due to misalignment of the generator within the cartridge body. If it is not square with the top and sides of the cartridge body, electronic azimuth adjustment will tell you to adjust the cartridge body off the 90 degree angle with the LP, so that the generator itself ends up 90 degrees to the plane of the LP surface. I think this is most often the real problem. My only issue with your angle of adjustment is to wonder whether prolonged use might ultimately result in either aberrant wear on the stylus tip or wear on the suspension, due to the angles of the force vectors thus created. John Ellison used to say, and may still say, that if the angle is more than 2 degrees off 90 degrees, you've got a problem that is best rectified by replacing the cartridge.
In my personal experience, I have a Koetsu Urushi that ended up noticeably off center when I adjusted azimuth using my Signet Cartridge Analyzer (a vintage piece). Moreover, it did not sound very good. After pondering this dilemma, I decided to ignore theory, and I set up the Urushi so it was at 90 degrees azimuth, disregarding the meter entirely. It sounds MUCH better that way. And I don't worry about the nature of the wear on the stylus/cantilever.
I think it is far more important to have the tip (azimuth) perpendicular to the groove (particular for Line Contact types with a large bearing radius). For an elliptical tip (made with front and back face cuts), this is important since the contact patch is pear shaped. A tip azimuth error will result in a different effective scanning radius on each wall. It is even more critical for a Shibata since the effective SRA is defined by the cut and the curving contact line will result in a differing effective SRA on each wall.
Aligning for tip azimuth may or may not correspond to the body being normal to the surface since cantilever rotation (and skew with MC) is incredibly common and the mounting tolerances for the tip itself are of the order of 1 degree (Expert stylus) for SRA and/or tip azimuth. Shure allow up to 3 degrees (I recall reading somewhere) and a recently purchased Ortofon 2M Blue would suggest that Ortofon allow up to at least 2 degrees error.
In my experience, aligning the tip itself results in a significantly cleaner presentation and improved imaging even if the channel balance is off for the lateral signal.
"Beauty is Truth, Truth Beauty.." Keats
in fact my experience with my Urushi is consistent with what you say, assuming that at about 90 degrees azimuth the tip of the Urushi stylus is perpendicular to the groove. It almost certainly is more nearly perpendicular than it was when I aligned for electrical perfection. This was using a Triplanar, so azimuth was easily adjusted and was no factor in my results.
However, by your preferred method, the only way to align for azimuth with real accuracy is using a microscope/camera capable of imaging the stylus tip in the groove. Yes?
Evidently, the OP aligned for EQUAL amounts of crosstalk in each channel, which I assume is why he reported only one value (-30db). There is another school of thought that says to align for lowest amount of crosstalk, regardless of whether the values for each channel are equal (usually they are not, when you adjust for lowest amount). I have sometimes found that adjusting for lowest crosstalk but not necessarily equal crosstalk results in less deviation from the 90 degree ideal.
Yes! I do indeed use a USB microscope with a mirror, then scrutinize the still photo to refine the azimuth of the tip.
I appreciate that not everyone will have the tools at hand to use this method. However, the cost of very adequate USB microscopes is such that they are within easy reach of all but the most impecunious of audiophiles!
I definitely don't go for the "equal crosstalk" method as the channel imbalance and frequency response anomalies that affect nearly all cartridges to a greater or lesser extent will mean that one rarely gets "all of the stars in perfect alignment" as it were!
The reason for my rejection of the "equal crosstalk method" is that I have styli where the tip happens to be "perfect" in terms of perpendicularity with respect to the body and the channel separation was anything BUT equal which I put down to coil variances. If one went for equal crosstalk, one would actually introduce a significant tip alignment error and drop the crosstalk to a lower value. I did many experiments to prove to myself that the tip itself was the important parameter. Peter Ledermann stressed this in relation to the OLC tip which I had put on a Denon DL160 - Having seen the shape under a microscope, it is evident that it wouldn't tolerate much alignment error before it was no longer sitting in the groove sensibly!
"Beauty is Truth, Truth Beauty.." Keats
I don't go for equal crosstalk, either. For one thing, the best you can do is equalize crosstalk at the one test frequency, usually 1kHz. That doesn't mean you've achieved equality at other frequencies. I've never seen or played with the Foz, but I get the impression that it is designed to get the user to equalize crosstalk, but I certainly may be mistaken.
I agree with you on the importance of "tip alignment", but I would have guessed, and I always thought, that the reason most/many cartridges don't achieve optimal crosstalk numbers when the cantilever is perpendicular to the LP surface is due to off-axis orientation of the generator (coils and/or magnets) up inside the cartridge body. Which we cannot usually visualize directly.
reelsmith's axiom: Its going to be used equipment when I sell it, so it may as well be used equipment when I buy it.
I use the Turntable Basics alignment tool and have never had any trouble with set-up, sound, and tracking.
i have a grado me+ mounted on a 12.0 jmw and a soundsmith gold (modified denon) mounted on a 12.7 jmw. having used the feikart software program and gotten the measurements to the max, they both tilt. the lyra i previously had on the 12.7 also tilted. just natural for the jmw arm i would say.
At THE Show last year, there was a vinyl rig with a cartridge tilted noticeably to the right (pic above, note the reflection off the vinyl). The person who set up the rig told me it had to do with the stylus being at an angle on the cantilever. The sound I heard seemed perfectly fine.....
When the cartridge is set up this way, the cantilever is now at an angle relative to the vinyl, not ideally vertical, viewed directly from the front. And because of that, I think this could pose an issue with tracking angle/rake angle over time. And also over time "skew" of the cantilever toward the upward side. The cartridge and magnet/coil assembly wants to see a perfectly vertical force relative to itself. The dilemma becomes which is more ideal, the cartridge seeing a perfectly vertical force or the two groove walls seeing equal pressure. (To avoid "skewing" of the cantilever, anti-skate might need to be increased if the cartridge is tilted left, decreased if tilted right. But the forces on the groove walls would become unequal.) I also think channel separation would suffer as well.
Thanks for your comments. Your logic seems good to me that there should be some negative consequences to this setup even though they may not be obviously audible. Unfortunately, the cartridge isn't new so I can't send it back. Any thoughts on whether this setup is more likely to cause damage or excessive wear to the records being played? I guess that is my major concern. I don't have the budget for a new cartridge right now but maybe I can get my Zu-103 retipped sooner rather than later.
but you say it is compensating for the crooked needle. Well, then OK.
You will be a lot happier in the long run. The other reason is that azimuth adjustments will tilt the cartridge and many cartridges have slightly crooked cantilevers and therefore it should be a little tipped over. The Soundsmith guru has explained that a little off should be expected and it will work the same. Have fun.
You have omitted telling us about the major deciding factor. Does it sound better one way or the other?
If it sounds the same either way then you may prefer to have a nice symmetrical visual presentaion. Otherwise the answer should be obvious to you.
How it sounds, as pointed out by PAR, is always the final determinate, and it's my experience that Azimuth is at least as important as SRA.
Have a record with annoying sibilants as do I, like that horrid Diana Krall Classic LP, "Love Scenes" or Alison Krause/Union Station "New Favorite"? Sibilants were tamed on both using the JMW Azimuth adjusting ring.
I found that leaving the inner Allen Key just loose enough so that moderate pressure was required to move the ring with the outer key loose, just as you do with one of the headshell screws when adjusting cartridge overhang, eliminated overshoot and the need to tighten that pesky inner key every time you wanted to try a setting.
I also pass along the function of the cardboard sleeve the Azimuth Adjusting Rod arrives in as what, in woodworking circles is known as a "Winding Stick". Place the Rod in the headshell groove and the cardboard in front of the cartridge on a record then sight across the top of the cardboard. You will either see the left or right end of the rod visible above the cardboard indicating out of alignment or the rod clearly level in relation to the cardboard.
Keep in mind that for a variety of mechanical reasons, the winding sticks will only show you in the ball park.
That done, begin the listening test, and remember, if it were easy, everyone could do it ;-}
you can not rely on the horizontal position of the VPI rod. It nearly never tells you if the setting is correct.....perhaps in the ballpark, but not in the best seat.
Thanks for the reply. Unfortunately I've only listened in its current configuration. Your suggestion is a good one, though I was hoping somebody would tell me the tilt didn't matter since I'm not anxious to fiddle with the azimuth on the unipivot again. I know there are tools to help with this but I've been too cheap to buy one so far.
" I'm not anxious to fiddle with the azimuth on the unipivot again"
I sympathise with your feelings on this knowing VPI unipivot arms myself (well, one of them). You could try one of Soundsmith's "Counter Intuitive" gizmos. It won't tell you what is the correct azimuth but will allow you to adjust it whilst retaining VTF or vice versa.
"If you prefer you can rotate the azimuth ring to set azimuth instead of rotating the counterweight."
I don't know if all the VPI tonearms have this but it makes azimuth adjustment easy.
Have Fun and Enjoy the Music
"Still Working the Problem"
Yes. My arm does not have the rotatable azimuth ring. I'll probably pick up the Soundsmith gizmo eventually but I guess I have to suffer for a while first. :)
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