Well I'm certainly no authority here, and will try "humbly" suggesting something. I certainly do recognize the peerless quality of both Arm/Cartridge you are using, and gather that you have much good experience with this high level of quality components.
What I thought of, was something more likely amiss with your Phono Stage, or Step Up, or Pre-Amp? In that perhaps it's just coincidental to be seeming like it's the Turntable-Cartridge that's causing this effect?
(Like there's something oscillating?, a bum Tube?, etc)
Can you somehow perhaps borrow-loan another Phono Stage to try?
Hopefully Doug D, and others here who have forgotten more than I know, can chime in, and better pinpoint this malady? Mark
Systems can be finicky in proportion to their refinement. Here are a few thoughts out loud....
I don't know anything about the Atmos, but if the cartridge is that new, I'd get it past at least 60 hours before worrying too much. Cartridges can act inconsistently from day to day during their break-in period. E-mail Mehran (?) and ask him what to expect for break-in.
If it is at a "particular place in the lp" - could the record have a small warp or bubble in that part of the groove?
Has there been any significant temperature or humidity change during the day to evening period where it happenened then didn't then did? I'm not sure if temperature/humidity can affect your cartridges compliance, but I suppose it is possible.
I doubt that compliance is the issue. The Triplanar and ZYX should be a good match. But since your symptoms sound like a similar experience I had , I'll relay it. Several years back I had mistracking issues with a Grado Sonata on a Premier MMT tonearm. Always on the first band of a side closer to the lead-in. I'd get mistracking on most any Telarc I played. It was an issue of stylus/cantilever compliance - Grado's were undamped (may still be for all I know) - which got sorted out as a cartridge/tonearm matching issue. When its not quite right, resonance can occur that causes what you describe as a 'flutter'. Increasing the effective mass of the tonearm or introducing some form of dampening both helped my situation somewhat, but not completely. You can change the effective mas by adding a gram of modeling clay to the headshell (and adjusting VTF) to see where that takes things. Dampening can be added by using some silicone (?) in the arm's dampening trough. You might observe the stylus/cantilever closely when the problem occurs to see if you notice any unusual 'wiggling' motion before and after experiments you may try. Again - unlikely that its compliance, but those are my thoughts.
The Tri-Planar arm has an adjustment for where the anti-skate starts to take effect. There is a small mono-filament line which is connected to the anti skate arm. This line can be adjusted so the anti skate takes effect as soon as the arm is lowered. If out of adjustment it could cause your problem. Start with 0 anti skate and when the arm is lowered check for slack in the mono line. If adjusted correctly there should be no slack in the line when the arm is first lowered. There is a small set screw which allows tension adjustment of the mono line. It is a bit tricky but not difficult.
Many Tri planar users have removed the dampening trough altogether. I have never needed additional dampening with my Tri planar Universe combination.
You have a great match between the ZYX and the Tri planar.
Yes, Mehran, the dealer for the Cart may be of help.
Only other thing that comes to my mind, is a possible slight bind, or some slight resistance in the Triplanar's bearings? How hard would this be to check?
After reading Doug's "tips and tricks" on this Arm, it sounds quite sophisticated, and complicated as well. Odd though how you say it's noticeable on a particular spot of the LP as well?
It's hard for me to suggest you playing your most treasured LPs to see if this problem exists as well with them, as if there is some mechanical issue (Stylus-Tonearm) I sure wouldn't want to see you damage this vinyl in a "sacrifice" test. Mark
Thanks for the info gentleman. Always appreciated. One thing I noticed, and I have not had a chance to play around today, is that volume made a difference. Right now I know my TT is insufficiently isolated, I can jump on the floor and have the needle mistrack lightly. Plus my speakers, for the time being are maybe 5 inches feom my table. I will be getting a rack soon that will move the TT well away from my speakers as well as provide better isolation and dampening.
But here's what happened. When I had the volume set high, and i dropped the needle, set the mute switch to operate, the "mistracking would occur. When I lowered the volume some, did the same process, no mistracking. Then I would turn the volume up to the desired level and no mistracking.
I did this expereiment based on watching the needle through a mag glass and seeing it mistrack with certian responses with the speaker.
Has anybody else ever experienced this? I certinaly will invetigate further the point where AS engages as well because I am assuming, I should be able to drop the needle at any volume i like?
Again, thanks for the help.
Mariasplunge said " because I am assuming, I should be able to drop the needle at any volume i like?"
I say that no you should not be able to "drop the needle" at any volume you like. Properly adjusted a "hi-fi" system will not like a needle drop or a "needle pick-up" either. There is a lot of energy being produced when you do this, much more so than the recorded LP dynamics. I do believe that at the correct playback level this may be a problem because of this. Your system should be able to handle the dynamics in anything but the most severe needle drop or abuse at your systems capabilities however.
Tough to evaluate, but I will comment a big "no" on your last sentence. Unless you are saying that with your system "muted" it still mistracks? Tough to understand your last post, can you elaborate better please?
Without better isolation, I doubt it would make a difference if the Turntable is all the way across the room if your system throws enough SPL's. Do you have Headphones? Try playing as loud as you like, or at different volumes through the Phones.
This will at least eliminate any acoustical interference.
My System is nowhere near as expensive as yours, just a measly VPI HW-19 MK-IV, with AQ Arm, Ruby 3 Cartridge, etc, but running two Mac Amps, four JBL Speakers, and a Sunfire MK-IV Sub to boot, I know I can have that Stylus fly off the record as if I dropped a brick on the Table, with such wake the dead volume. lol
You can also slam your car door if you like.
... watching the needle through a mag glass and seeing it mistrack with certian responses with the speaker.
... When I lowered the volume some, did the same process, no mistracking.
... my speakers, for the time being are maybe 5 inches feom my table.
It kinda sounds like you diagnosed your own question.
Does it mistrack through your cans? If so, then it's a tonearm/cartridge problem. Since you say you've realigned the cartridge, then I'm thinking it's the antiskate, either not set at the right level, or binding. Is the mistracking always in one channel? If so, then it's too much or too little anti-skate.
The fact that it can be intermittent makes me thing its some binding in the anti-skate.
I don't know how, but the other night I noticed the anti-skate thread that holds the weight was out of its loop. It was binding and at times and causing similar issues to yours.
It certainly sounds like acoustic feedback. The Atmos, being almost fully nude, is likely to be sensitive to that. It gave us no problems on our rig, but I can bounce up and down next to our table with no audible feedback, certainly no skipping. Speakers 5" from the tonearm? Yikes!
You need to address those issues I guess. You could confirm the diagnosis by listening through headphones, as Markd51 suggested.
P.S. to DocSavage
There's an easier way to adjust the a/s initiation point on a TriPlanar. Don't fiddle with the set screw holding the fishing line. You're as likely to break the line as anything, trust me! ;-)
Just adjust the pin sticking out of the front of the bearing cage (just below the dogleg). Swivelling that pin up or down controls the a/s initiation point.