I'm scratching my records


After carefully setting the stylus pressure using a scale (to the lower end of the Lyra Helikon's recommended setting) on my JMW 12.5, the needle will 'skate' when initially placed on the lead-in groove until it 'hits' the music tracks and makes a horrible and damaging sound...(Now my Norah Jones LP has a minutes worth of 'tic-tic-tic-tic' :(

Is my stylus pressure too low, or too high?

Not all records do this, maybe 30%, and if I'm careful to get the stylus very near the music start and away from the edge as much as possible it helps.

Suggestions, comments, criticism??? All appreciated.

Damn, this analog is hard!

John
Atlanta, GA
jbatlanta
John,

You've actually asked two questions, one about cueing a record, the other about Vertical Tracking Force. A perfect VTF setting will not prevent what happened to Norah. :( The ideal setup is optimized to let your stylus accurately trace a groove it's already in. Decelerating a stylus on a sideways-sloping glaze of ungrooved vinyl would require a very different, and horrible sounding, setup. Let's address these two questions seperately.

SETTING VTF
I don't know the JMW or Helikon, but most top cartridges work best in the upper half of their recommended range. It is a popular misconception that lighter VTF is good for your records. Precisely the opposite is true. It's hard to think of anything worse for a plastic groove than sending a diamond spike bouncing back and forth between the walls due to inadequate controlling pressure. Optimal VTF will control the stylus just enough to let it trace both groove walls accurately without over-damping.

The way to set VTF is by listening to music with a lot of dynamic, HF content. If VTF is too low, HF's will sound shrill or broken up. If VTF is too high, HF's start to disappear altogether.

CUEING RECORDS
The problem is the stupid record manufacturers, who invented raised edges to seperate records from each other in a stack on a changer. Anyone who stacks records on a changer should get the scratches they deserve. Why make the rest of us suffer? (Many 200g audiophile pressings have a nice flat lead-in area and lots of lead-in grooves, not just one or two.)

That little downslope is a terrible risk. ALWAYS look for that. If the record has one then you've already discovered the solution. Place the stylus as near to the bottom of that slope as possible, erring toward the music side if necessary. Better to miss the first few bars than destroy them forever. If the record seems dodgy for cueing accurately I'll control the stylus drop speed myself, not just trust the damping. This is especially important if the record is warped.

Damn, this analog is fun!
John,little noise is acceptable when the stylus hit the lead-in groove,not damaging sound.

Try 1.5 gram and see what's going to happend !

Analog isn't easy to set up,but you'll have smile on your face when it's set properly.

CD isn't easy for the ears !!!
It sounds to me like you may also need to adjust the antiskating force. If it is set too high, or too low, it will cause the tonearm to swing rapidly toward (or away) from the spindle when the stylus makes contact with the record.

There are test LP's that are helpful in setting the antiskate force, but if you don't have one, you can also try using an LP that has a blank section with no grooves. Set the stylus down on the blank area, and then adjust the antiskate until the tonearm remains stationary (neither moving toward nor away from the spindle).
John,

The last individual had it right: the problem is your antiskating force. Since the VPI tonearm doesn't have this feature, you must twist the tonearm wires in the direction opposite to the skating direction, clockwise if you're facing the front of the 'table, and then connect them. If one twist isn't enough, then try two. Also, don't be afraid to increase the stylus force pressure, as too little does more to damage records than too much. Do this before you twist the wires, as the skating force is tied to the pressure. Head toward the upper end of the recommended range.
I agree with SDcampbell that insufficient anti-skating force could contribute to this problem, but I disagree with the suggested method of setting it.

Skating force is a function of friction and offset angle: the record groove moving past the stylus pulls upon it at an angle to the stylus-pivot line, causing the arm to swing inward. If the stylus is not riding in a groove, the friction acting upon it will be much lower, so the resultant skating force will be proportionately reduced. Skating force even varies with the dynamics of groove modulations, because larger modulations result in more friction. Adjusting one's anti-skating to compensate for the much lower force of a flat surface is unlikely to correlate well with the actual skating force that occurs when the stylus is in a modulating groove.

I'm also not sure it's a good idea for the stylus to be run while resting on its point. Maybe harmless, but it wasn't designed to do that and clearly the tip must be the most vulnerable part.
You might also check to make sure you are starting with a LEVEL table. No insult intended; just good to check the basics since what you are experiencing is consistent with a turntable on a slight tilt.
DD is right - you're tacking force is probably set too low, but SDC is also right, because correct anti-skating force is determined by tracking force (more = more), and with a VPI 'arm, chances are you're employing very little to no anti-skating force at present if you haven't made the 'wire-twist' adjustment (or the dealer hasn't). I would second the recommendation for a tracking force in the top half of the specified range - or even just go straight to the very top when in doubt, and then you can experiment with auditioning slightly lighter VTF's, if desired, after your problem has been identified and rectified. I would stay away from trying to track at the bottom of your cart's listed VTF range - in most cases it will sound worse, and can cause far more record (and needle) wear if it's too light than if it's 'too' heavy (the recommended range will never really be 'too' heavy, as you can observe by looking at the degree of deflection exhibited by your cantilever's suspension when the tonearm is lowered - there will still be plenty of vertical travel available even at the max recommended setting).

DD is also right about the shape of the lead-in groove 'shoulder' on some LP's being more treacherous than others, but I wouldn't worry about the impact of groove modulation on skating forces. In fact, the way tracking force is set correctly using a special test record is for the stylus to be lowered during platter rotation, in the middle of the 'arms radial travel (the central area of the record's playing surface, about halfway between the lead-in and run-out grooves), on a smooth, *ungrooved* 'track' included for just this purpose, and the anti-skate is then set so that the needle tracks this grooveless area straight, without wandering toward the record's label or edge (this must be done after the tracking force has been set). Since VPI 'arms do not have a calibrated anti-skate control, I would suggest you should pick up such a test record.

Other than that, I also think it is a good idea to become comfortable and competent with cueing by hand, if you're used to depending on the cueing lever. It's tough to precisely line up the needle over the desired groove area with the 'arm being held aloft via the lever control, but you can also get a 'feel' when cueing by hand - unavailable via the lever - for whether or not you're in the 'sweet spot' of the Track #1 lead-in area just prior to releasing the tonearm, and you can reposition and make adjustments before letting go if it feels wrong. With the lever, you have to actually see the problem occur first, and then there's always a slight delay in the lifting action once you've decided to abort that can prove fatal. It takes a little practice, but once you've gotten adept at hand-cueing, you'll never go back to using the lever except maybe when the phone/doorbell rings during listening.
Nice post Zaikesman, excellent advice. Considerable physical involvement is necessary to play LP's properly anyway. Why not cue manually?

I'd forgotten that a JMW lacks any real antiskate mechanism. If his wires aren't twisted (or worse, if they're twisted the wrong direction) the lateral acceleration on that downslope will be even faster.

Happy New Year to all!
Thank you for the suggestions. I have found that my tracking force was only 1.5G, this for a Lyra Helikon that recommends 1.6 to 1.75G! So, I have now upped the force to 1.7G and the stylus seems to stay put better. Also, the distortion I was hearing during very loud passages is gone...(I suspected the force was too low, but hadn't had the time to adjust it)

Well, today I have the time...am watching football with the sound off, and the stereo on (turntable of course), in front of the fireplace...aaaaaaah!

My only hassle is from two cats giving me dirty looks as evidently my music is interfering with their nap time!

I'll put something more restful on, I guess. :)
Actaually I spoke with Wally a few days ago and had so many questions all over the place I forgot to ask what his anti skate would go fo.But he did say that he heard that VPI was issuing it's own anti skate but he thought his would perform better.He than said while he thinks VPI puts out a great product he was in the anti skate is manadatory camp sonically and to protect stylus and LP's.Anybody out there used his VPI tuning kit?