IPB

Welcome Guest ( Log In | Register )

 
Reply to this topicStart new topic
more tonearm/cartridge adjustments, some peculiar results?
AndyH-ha
post Aug 14 2010, 08:18
Post #1





Group: Members
Posts: 2207
Joined: 31-August 05
Member No.: 24222



Not long ago something happened to the stylus of my cartridge. One day the end of the cantilever, with the stylus, fell off. It probably had done only a few hundred LP plays so it should have been good for quite a long time yet.

Fortunately I had another new stylus, perhaps one of the last in captivity. Shure no longer makes them for the V15VxMR. I just plugged in the new stylus assembly and everything seemed fine.

I started to worry about this a bit however. I looked into the M97xE stylus, as rumor has it that it fits the V15V cartridge. Looking at the Shure website for information, I saw the N97xE, the stylus for the M97xE cartridge, marked as ďnot available.Ē This was even more worrying as no aftermarket stylus has appeared for the V15V.

I located a dealer who had them in stock and bought one. Today, perhaps inspired by the recent HA thread on cartridge setup, I decided I might as well check the tracking weight before testing the new stylus, as I had not touched any adjustment since remounting the cartridge several years ago. The V15VxMR setup guide says 1.0 grams track force is optimum, 1.25 grams is maximum.

When I had the Shure force gauge up to almost 3 grams, nearly its maximum measurement, and it was still plopping all the way down on the cartridge side, I just started over with re-balancing the tonearm in floating mode (bias adjustment off), then adjusted the tracking weight to 1.25 grams. Then I got out the alignment gauge.

The stylus came down about 3mm short of the proper target????? I had to loosen the cartridge in the tonearm head, then reposition and realign it. Then I had to readjust the tracking weight to get back to 1.25 grams. Fortunately the cartridge alignment did not seem to be effected by this second tracking weight adjustment.

I set the bias to the position on the dial it had before I started today. Then it was time for the HFN&RR test LP. all track observations below are of recordings made in CoolEdit, zoomed in very close. Things did sound in accordance with what I saw on screen, which was gratifying, but I trust what I see more.

The +12dB bias setting track was nice and smooth, the +14dB bias track less so. (there is a point of sorts for all this verbiage). I reduced the bias setting and the +14B track eventually became nice, smooth and even, but the +16dB one was much less so.

I switched to the other side and tried the center +15dB track. This was less than stellar but by turning up the tonearm weight a degree or two at a time, I finally got it looking pretty good. At first I though everything was smooth and even but eventually I realized there were occasional bits of mistracking every now and then as the recording progressed. I have no way to tell if this is actual mistracking or damaged LP.

The inner and outer +15dB test tracks both showed mistracking at the screen bottom peaks of the right channel (minus swing, I presume). I could not seem to improve that much , although I wasnít keen to up the tracking force more. The middle track was good as is, and the tracking force had to be above Shureís stated maximum.

The +16dB bias track on the other side still looked much the same after the tracking weight increase (not so good) and bias adjustments could only make it worse.

In went the M97xE stylus assembly. I made no more tone arm adjustments. All the tracks recorded more cleanly than with the V15V stylus. The +16dB bias track still wasnít perfect but it definitely looked better. The inner and outer +15dB tracks on side 2 still showed the same mistracking, but to a lesser degree than with the V15V stylus. Most or all of the tracks I tested show longer stretches with no mistracking evident, just nice even sine waves. Strangest of all, the M97xE stylus produced +3dB greater amplitude.

The M97xE specs say 0.75g to 1.5g tracking force, vs 1.0 to 1.25 for the V15VxMR. The specified output voltage is 4.0mv vs 3.0mv for the V15VxMR. While those specs might say I could safely use a greater tracking force with the M97xE stylus (how involved is the cartridge itself in setting this limit?), surely it is the cartridge more than the stylus that is responsible for the strength of the cartridge output, no?

The new V15VxMR stylus that I installed not long ago has perhaps not been used on more than 25 or 30 LP plays so far. Of course it was apparently being forced down far too much by too high a tracking weight, so maybe that damaged it and accounts for the poorer performance. I did not touch any adjustment when I originally put in that stylus, so maybe a high tracking weight is also what broke the previous cantilever.

In spite of this, or maybe because of it, the music Iíve been recording sounds good, at least to me, and shows nothing strange on screen. I have played nothing but the test LP tracks since finishing the tonearm/cartridge adjustments this evening, so I donít actually know about music with the new setup.

The final current tracking force measures as just under 1.4g. I donít know whether to leave it there for apparently better tracking or reduce it for stylus safety. It was set with the V15VxMR stylus and that is the stylus I intend to use now, keeping the new N97xE as eventual replacement. Anyone have any experience with exceeding Shureís maximum setting?

By the way, according to a Shure support person, the M97xE stylus will only fit the V15VxMR cartridge, not any other version of the V15V. She also said Shure has never tried the stylus in the cartridge and so knows nothing about how it might work or not work, only that it will fit.
Go to the top of the page
+Quote Post
AndyH-ha
post Aug 14 2010, 19:26
Post #2





Group: Members
Posts: 2207
Joined: 31-August 05
Member No.: 24222



Both my experience reported here and the findings reported in the Stanton TT setup thread suggest that the idea that mistracking an LP once produces mistracking on subsequent plays, regardless of the current setup, may be largely a myth.
Go to the top of the page
+Quote Post
cliveb
post Aug 15 2010, 09:44
Post #3


WaveRepair developer


Group: Developer
Posts: 842
Joined: 28-July 04
Member No.: 15845



QUOTE (AndyH-ha @ Aug 14 2010, 19:26) *
Both my experience reported here and the findings reported in the Stanton TT setup thread suggest that the idea that mistracking an LP once produces mistracking on subsequent plays, regardless of the current setup, may be largely a myth.

It is by no means certain that mistracking will damage an LP. Whether it does so depends on a lot of factors - the severity of the mistracking, the stylus shape and condition, the formulation of the vinyl, and probably other factors I've missed. Probably in many cases you can be lucky and the LP will survive. But this doesn't alter the fact that it is *possible* that an LP can be trashed by just one instance of serious mistracking.

Returning to your first post, as I read it I got the feeling that you are focussing too much on trying to successfully track the "torture" cuts on your test LP. While the V15 is one of the very few cartridges in history that might be expected to pass these, if you have a sample that doesn't, I wouldn't lose too much sleep over it. My cartridge (a medium complicance moving coil) gives dreadful results on these kind of test records (the +18dB cut generates a dreadful sawtooth "buzzing"), but I've *never* heard it produce obvious mistracking on actual music LPs - they simply don't have these kind of grooves. (Mind you, I don't have the Telarc 1812!)

If I were you I wouldn't exceed the maximum tracking force for the sake of improving trackability on test records. Doing so probably pushes the cantilever suspension out of its optimum position, and/or the magnet might be moved to a position relative to the coils that generates less linear responses. A large out-of-phase signal could then lead to trouble.
Go to the top of the page
+Quote Post
Knowzy
post Aug 15 2010, 09:59
Post #4





Group: Members
Posts: 128
Joined: 15-July 08
Member No.: 55856



QUOTE (AndyH-ha @ Aug 14 2010, 11:26) *
Both my experience reported here and the findings reported in the Stanton TT setup thread suggest that the idea that mistracking an LP once produces mistracking on subsequent plays, regardless of the current setup, may be largely a myth.

I can't answer the question but I can offer up some samples.

I played that middle track 21 times before sampling, several of them severely mistracking (listen to 2.25 grams).

It was a brand copy of HFN002. I first played it at 4 grams. The 17th play was also at 4 grams.

Maybe some patterns appeared between the plays.


HFN002 Trackability Test
300Hz sine @ +15dB, Center of Record

I have around 30 tracks of 300Hz sines, mostly that same, center track. Just ask if you'd like other samples.




Mistracking was this severe.

Trackability Test @ 2.25 Grams


Go to the top of the page
+Quote Post
AndyH-ha
post Aug 16 2010, 01:13
Post #5





Group: Members
Posts: 2207
Joined: 31-August 05
Member No.: 24222



The three +15dB tracks on side two are the only ones labeled for tracking ability.
Only the +18dB bias setting track on side one is labeled as a ďtorture test,Ē with recommendations that one should be satisfied without conquering that rack if the lower level three tracks (+12dB, +14dB, +16dB) can be navigated properly. I reported three out of these six as less than satisfactory.

Of course other viewpoints are possible. Most likely the quality of the tonearm is a significant factor in how well tracking can be done. While cost and quality are sometimes far removed from each other, it is likely that only the relatively well to do can exercise much control over true tonearm quality.

The last time I set up the tonearm and cartridge I started with the specified maximum of 1.25g and never afterwards changed tracking force (or at least I so believed). Only the bias and cartridge alignment were manipulated to get the best results I could manage.

I donít remember what those results were, but a while back, quite some time after the setup, I made a recording of the entire LP for some tests/comparisons Axon wanted to do. Looking closely at that recording recently is what decided me to attempt some improvement when I got the new stylus assembly, which led to redoing the entire setup, as described in my first post.

I take the point about possible damage at the tracking force I have now. A worry about that is what led to this thread. Possibly there is already damage if the high tracking weight I thought I measured as the first step was correct. I would like to ask Shure but I have not been able to find a support email address. I guess paying for a long distance telephone call is the only option.
Go to the top of the page
+Quote Post
AndyH-ha
post Aug 16 2010, 21:17
Post #6





Group: Members
Posts: 2207
Joined: 31-August 05
Member No.: 24222



It occurred to me as I awoke this morning that perhaps there is some vector error in the tracking force measurement. Is that a nonsense idea? If not, is it relevant?

General setup instructions are to set the bias to zero, set the tracking force, readjust the alignment as necessary, then set the bias. After these steps I began tweaking tracking and bias to get the best playback from the test tracks.

As the first step of balancing the arm, I adjusted the tonearmís own force gauge to zero. I then set the tracking force with the stylus force gauge, which advanced the tonearm gauge reading accordingly, but unfortunately I did not pay any attention to its reading.

During the tweaking I advanced the tracking force weight a few times, but turning it only a degree or so each time. According to the tonearm gauge, the final weight is barely off 1.25g, but I donít know anything about its readings in-between now and when I set it to zero. Considerable time was spent getting to the best tracking and Iím not keen to start over just to be able to observe the tonearm gauge reading.

So, the vague thought rattling around in my head: that tonearmís gauge will not be effected by the bias setting but perhaps the final reading on the stylus force gauge is some summing of the two, tracking force and bias.

Even if that is true, it might not mean anything in terms of the maximum allowable tracking force measurement. If the stylus force gauge is still the proper instrument to use at this point, it does read 1.4g. If the stylus force gauge can only be read directly (without any correction factor) when the bias is zero, I cannot rely on it because I donít know what the correction factor is. Any thoughts on that aspect?
Go to the top of the page
+Quote Post
WernerO
post Aug 17 2010, 07:53
Post #7





Group: Members
Posts: 74
Joined: 21-November 06
Member No.: 37858



QUOTE (AndyH-ha @ Aug 14 2010, 09:18) *
This was even more worrying as no aftermarket stylus has appeared for the V15V.


JICO make aftermarket styli for most Shures, including V15MR, V15xMR, and M97xE.

http://www.export-japan.com/marketing/styl...e=1&sort=3d

They are affordable and, as rumour has it (I have no experience), often superior to the original.

QUOTE (AndyH-ha @ Aug 14 2010, 09:18) *
surely it is the cartridge more than the stylus that is responsible for the strength of the cartridge output, no?


Signal strength is governed by coils, magnetic circuit, and actual magnet. With a standard MM like a Shure the magnet is in the stylus assembly.

QUOTE (AndyH-ha @ Aug 14 2010, 09:18) *
By the way, according to a Shure support person, the M97xE stylus will only fit the V15VxMR cartridge, not any other version of the V15V. She also said Shure has never tried the stylus in the cartridge and so knows nothing about how it might work or not work, only that it will fit.


Both 'x' cartirdges share the relevant dimensions and thus have interchangeable assemblies.

You can read my review of the M97xE with standard stylus and with VN5xMR here:

http://www.tnt-audio.com/sorgenti/shure_m97xe_e.html

I must say I haven't been impressed with Shure's performance and behaviour, lately.

Go to the top of the page
+Quote Post
botface
post Aug 17 2010, 10:00
Post #8





Group: Members
Posts: 355
Joined: 14-January 08
Member No.: 50483



QUOTE (AndyH-ha @ Aug 16 2010, 21:17) *
So, the vague thought rattling around in my head: that tonearmís gauge will not be effected by the bias setting but perhaps the final reading on the stylus force gauge is some summing of the two, tracking force and bias.

I wouldn't rule out any interaction between tracking weight and bias with respect to a stylus force guage reading - it depends how bias is applied to the arm in question - but I don't think it would make any significant difference even if there were. You mention having a Shure stylus pressure guage. If it's the SFG-2 you should be able to get the stylus to stay in the groove on the lever even with bias set. So, I'd give that a try if you haven't already. Ultimately I'd take the reading from a decent stylus pressure guage over what the arm's readout says.

One final thought - and I don't mean to insult your intelligence - but when you initialy balanced out the arm with tracking force and bias at zero were you careful to enure it was floating perfectly horizontally (some people prefer it to be floating just above, almost touching, a record to slightly better mimic the real world situation when actually playing a record)?
Go to the top of the page
+Quote Post
Knowzy
post Aug 17 2010, 17:32
Post #9





Group: Members
Posts: 128
Joined: 15-July 08
Member No.: 55856



QUOTE (botface @ Aug 17 2010, 02:00) *
Ultimately I'd take the reading from a decent stylus pressure guage over what the arm's readout says.

I'm beginning to put little faith in the dial on the tonearm. The Stanton I tested was off too, by over 1/3 of a gram at the high end.

I was measuring with the bias set to 0.


Go to the top of the page
+Quote Post
AndyH-ha
post Aug 18 2010, 01:30
Post #10





Group: Members
Posts: 2207
Joined: 31-August 05
Member No.: 24222



The tonearm tracking force scale, at least on my TT, provides no absolute reading. It has to be calibrated by setting its zero point coincident with the floating tonearm position. That operation is clearly enough defined -- adjust the tonearm weight so the tonearm is floating parallel to the TT platter surface. One can even hold a bubble level up near the tonearm to verify what one sees, but it is still ultimately an eyeball estimate.

However, the scale itself is large enough to easily estimate 1/10th gradations between its 0.25 grams markings, and it appears to be linear. The force adjustment, turning the tonearm weight on the finely threaded tonearm end, is linear withing the accuracy of the threads. I think this should lead to the scale reading being very reasonable relative to where it was zeroed.

If the initial zero adjustment was good, and if the scale markings are indeed relevant to the thread pitch, the offset reading relative to the zero point should be valid. With some care, it is easy to keep the tonearm scale in position after setting itís zero point, but it is pretty easy to move it if one isnít paying attention when one adjusts the tracking force. Unfortunately, I didnít not pay any real attention to the tonearm scale, thinking the stylus force gauge would be better.

I went through too much time and effort to want to start over to see what happens with the scale. Did it read 1.25g when I set the initial tracking force to that value, as measured by the stylus force gauge? Since I donít have information on the final accuracy of the tonearm gauge calibration, I need to know if the stylus force gauge reading is still valid after the bias adjustment has been made, or if it is only valid with the bias set to zero.

This isnít about any difficulty making a measurement, there isnít any difficulty with that. It is only about what the measurement means, which is probably either
just what it reads
or
with the bias set, it does not mean anything unless one can apply a correction factor that takes into account the properties of that particular bias mechanism and the value of that correction for the particular bias force applied (which factor might be very non-linear).


Iíve see JICO styli offered for several Shure cartridges but not the V15V, so I did not think it existed. Affordable is relative to oneís means. However, their V15VxMR replacement stylus, on their web site, is quite a bit cheaper than the shure original was when it was available. I donít know what that would come to with shipping. The M97xE JICO stylus offered by a U.S. retailer was nearer 3X what I paid for the Shure version.
Go to the top of the page
+Quote Post
AndyH-ha
post Aug 18 2010, 06:25
Post #11





Group: Members
Posts: 2207
Joined: 31-August 05
Member No.: 24222



I measured tracking force with the Shure gauge. It still measured
as I remembered. I set the bias to zero. The tracking force measurement did not change. I moved the arm around several times, to assure nothing was sticking. No change. After resetting the tracking force, I again measured with and without bias. Still no change in tracking force by changing the bias. The tracking force gauge measurement is independent on the bias setting, at least for the mechanism of my TT.

I also adjusted the tonearm gauge to equal the stylus gauge measurement. Then I moved the tracking force up and down a few times, measuring the result with the stylus gauge. The tonearm gauge stayed right on.

I started over with zero bias and set the tracking force to the specified maximum of 1.25g. Thereafter only the bias setting was adjusted, no more changes to the tracking force.

At 1.25g tracking force, and the bias a little less than 1.0, all three tracking tracks on side two, and the +12, +14, and +16dB tracks of side 1are very good. The +18dB track is not satisfactory but mainly only in the right channel. The distortion of the left channel sine wave is very small, occurring just at the peaks, but the right channel mistracking is fairly large.

These results are definitely better than from the previous attempt reported above. They are actually the result of ď3rd timeís the ...Ē as I realized an error in procedure while working through attempt #2, forcing me to go back to the beginning again. I realized I had made the same error the first time. I think it gets a little easier with practice.

The inner and outer tracking tracks of side 2 (all side 2 is +15dB) also show a little mistracking on the right channel, mainly before I turned on the bias. Since only the right channel has mistracking in all three instances, I would guess some cartridge alignment problem. Alignment is not very easy so Iím not sure that my best effort produced the best results possible.

If Axon is reading, and still interested, these recordings from the HFN&RR definitely show better tracking than the recording I sent at your request when you were making whatever tests you were making.
Go to the top of the page
+Quote Post
botface
post Aug 18 2010, 09:14
Post #12





Group: Members
Posts: 355
Joined: 14-January 08
Member No.: 50483



QUOTE (AndyH-ha @ Aug 18 2010, 06:25) *
Since only the right channel has mistracking in all three instances, I would guess some cartridge alignment problem.

It could also be inadequate bias. You could try increasing it and see if the right channel gets any better
Go to the top of the page
+Quote Post
AndyH-ha
post Aug 19 2010, 11:29
Post #13





Group: Members
Posts: 2207
Joined: 31-August 05
Member No.: 24222



Bias seems optimum. Turning it either up or down only seems to make things worse. With the bias adjustment set, the right channel mistaking on the inner and outer tracks of side 2 is very small. Changing the bias either way seems to make it worse. Only the +18dB track has very much mistaking. Even if this track can be improved by some more extreme bias setting, it does not seem worthwhile to lose the quality on the more normal tracks.

Since all the mistracking I see is in the right channel, regardless of bias setting, alignment seems like the more likely cause. There is a gauge of sorts (the alignment protractor, in several variants) to use for overhang, but most of the adjustments are mainly by eyeball. Many tonearms, like mine, donít have adjustments for azimuth or vertical tracking angle.
Go to the top of the page
+Quote Post
Arnold B. Kruege...
post Aug 20 2010, 13:49
Post #14





Group: Members
Posts: 3797
Joined: 29-October 08
From: USA, 48236
Member No.: 61311



QUOTE (AndyH-ha @ Aug 19 2010, 06:29) *
Bias seems optimum. Turning it either up or down only seems to make things worse. With the bias adjustment set, the right channel mistaking on the inner and outer tracks of side 2 is very small. Changing the bias either way seems to make it worse. Only the +18dB track has very much mistaking. Even if this track can be improved by some more extreme bias setting, it does not seem worthwhile to lose the quality on the more normal tracks.

Since all the mistracking I see is in the right channel, regardless of bias setting, alignment seems like the more likely cause. There is a gauge of sorts (the alignment protractor, in several variants) to use for overhang, but most of the adjustments are mainly by eyeball. Many tonearms, like mine, donít have adjustments for azimuth or vertical tracking angle.


Adjustments like those can often be obtained by loosening screwws and adjusting, or shimming.
Go to the top of the page
+Quote Post
AndyH-ha
post Aug 20 2010, 20:55
Post #15





Group: Members
Posts: 2207
Joined: 31-August 05
Member No.: 24222



In theory! Maybe with access to micro vascular surgery instruments and nano production tools, and maybe a stabilizing force field that can keep things absolutely stable while rotating the entire setup to angle where one actually has a clear line of sight to the stylus/cantilever interface so that one could make a useful assessment of the effect of the changes one is attempting to implement. Otherwise just getting the bolts through the cartridge shell, getting the nuts onto the bolts, getting this setup into some alignment that seems like it might relate to the gauge, then tightening it into the alignment youíve spent so much time obtaining, without the tightening operation markedly altering the alignment -- even without additional tiny skittering add-on parts in the mix -- is a tremendous pita. And this is assuming, which seems like a very remote possibility indeed, that one could actually find some shims that are the right size and thickness.
Go to the top of the page
+Quote Post
Arnold B. Kruege...
post Aug 21 2010, 12:11
Post #16





Group: Members
Posts: 3797
Joined: 29-October 08
From: USA, 48236
Member No.: 61311



QUOTE (AndyH-ha @ Aug 20 2010, 15:55) *
In theory! Maybe with access to micro vascular surgery instruments and nano production tools, and maybe a stabilizing force field that can keep things absolutely stable while rotating the entire setup to angle where one actually has a clear line of sight to the stylus/cantilever interface so that one could make a useful assessment of the effect of the changes one is attempting to implement. Otherwise just getting the bolts through the cartridge shell, getting the nuts onto the bolts, getting this setup into some alignment that seems like it might relate to the gauge, then tightening it into the alignment youíve spent so much time obtaining, without the tightening operation markedly altering the alignment -- even without additional tiny skittering add-on parts in the mix -- is a tremendous pita. And this is assuming, which seems like a very remote possibility indeed, that one could actually find some shims that are the right size and thickness.


It's what some of us did beck in the day before CD.

Test records, lab measuring equipment, shims, screwdrivers, magnifying glass...
Go to the top of the page
+Quote Post

Reply to this topicStart new topic
1 User(s) are reading this topic (1 Guests and 0 Anonymous Users)
0 Members:

 



RSS Lo-Fi Version Time is now: 17th September 2014 - 06:56