I'm gonna sue for patent infringement. I posted that very tweak here months ago in considerable detail, though in the context of a different arm.
Harrrummmph!!!
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FWIW
I received my antiskate device today from Elusivedisc and the metal has been replaced with 2 small o-rings. Apparently, VPI watched the Fremer DVD and fixed the problem. |
Thank you. For about $30, I will pick up that DVD. |
Buy or borrow a voltmeter, the Cardas record and the Fremer DVD. All your azimuth questions will be answered in the video for setting up a Scoutmaster. Fremer demonstrates how to set azimuth and it is so slick and simple. I decreased the crosstalk of my Denon 103 from 3dB to 0.5dB and the imaging and soundstage change is amazing.
The set screw of my counterweight is clockwise of center from the front.
Sullygr |
Hopefully not hijacking this thread, but what did you guys notice if you had the set screw on the counterweight at dead center, thus the azimuth not "perfectly" set? I currently have a Scout with the JMW 9 arm and a dyna 20X-L cart tracking at 2.3 grams. Thank you. |
A follow-up on this old thread of mine... I recently got a chance to see Michael Fremer's turntable setup video, and he came to the same conclusion as I did - that the mechanical anti-skating mechanism from VPI provides far too much force even at it's minimum setting. Clever Mikey thought of something that never occurred to me, however. Install the A/S device and remove the counterweight from it! Apparently that will put you right in the ballpark of where you want to be. I'm gonna have to try that! |
After further inspection I believe you guys are right. I now see the set screws for adjusting the height of the entire assembly (so that you can make the fishing line parallel to the plinth) and the weight (so you can slide it along the shaft to adjust anti-skate force). I'm going to go yank my table out of the cabinet and play with these adjustments and see what happens.
Funny thing is the instructions that came with my anti-skate rig say nothing about adjusting these parameters--I just figured you adjusted the string height as a result.
Thanks everyone. I'll report back after I've made some changes and run the test disc again. |
Tfkaudio:
I had the same frustration setting the azimuth (which by the way, I have not figured out why VPI makes us adjust the azimuth and the VTF with the same counterweight, so that as you adjust one, you skew the other!!). My setscrew ended up just about where yours did after a couple of hours of trial and error setting and resetting. I use the Dynavector DX 20.
Now that it is dialed in though, it sounds real good.
Cheers. |
Dodgealum: I finally decided to install the mechanical antiskate on my Scoutmaster. My understanding is the same as TfkAudio's. The weight on the AS adjustment has a very small hex screw in it that holds it in place. You loosen that screw, and move the weight up and down the post. The manual that came with mine said to put the fishing line so that it is parallel with the table.
I would imagine that you can install this AS on a Scout, which has the junction box mounted on the plinth, rather than on the metal platform coming off the arm bearing housing, so that you would use a different position for the fishing line.
Anyway, that's my understanding. Maybe Mike will read this and chime in here.
Cheers.
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without looking at it, that sounds about right, maybe even a bit more. i know it's not dead center. |
Sberger, Once you got the azimuth dialed in, where was the counter-weight setscrew? Mine is a couple millimeters right of dead center on the arm tube (looking down on the arm, standing in front of the table). Just wondering if you and others arrived at the same place as I did...
Cheers. |
honestly the coffee stirrer trick didn't work for me. i use my eyes and ears. i try to get the cantilver& cartridge body as squared up as possible, and then listen. i'll use both mono and stereo lp's to get my center image as focused and stable as possible. once in a while i'll do a small adjustment after i reset vtf with a new cart, but normally i set and forget. |
Tfkaudio. Interesting. Either we have different anti-skate rigs or one of us is wrong. First, the weight on mine does not slide along the post--it is fixed in position closest to the fulcrum. It is immovable. If it did move the amount of anti-skate added or subtracted by moving the weight would be extreme indeed. This is why you move the fishing line on the other post--it provides a much finer adjustment. If you are somehow moving the weight along the horizontal post you are adding (or subtracting) significant weight and this, I would offer, is why your sound is getting screwed up. Second, I do not understand your description of how to position the string. You say position it so that it is parallel to the table when the arm is in the rest. Given where it mounts this is going to be exactly the same for each and every table. Why make it adjustable at all if it serves no purpose other than to be parallel to the table?
I'm of the opinion that you use the position of the string to adjust the anti-skate and that the weight remains fixed in position. I could be wrong here but what you suggest doesn't make sense to me. I even went over to my table to try to pull the weight toward the outer end of the post--it won't move.
I'd really be interested in hearing from others or, better yet, Mike from VPI on this one. |
Sberger, I've found setting the azimuth to be a challenge. What I notice is that, using the "coffee stirrer" method, I can get the stirrer parallel to the table, but when the stylus sets down on the record, it tips slightly away from the center. So I adjusted it so that the stirrer tips slightly toward center and evens out when it makes contact with the record. Did you have the same experience?
Cheers.
Tom |
Dodgealum, The 5 spaced indents don't influence anti-skate force. The weight on the other leg does. The fishing line should be connected to the indentation that makes the fishing line parallel to the table when the arm is in the armrest. You then slide the weight on the other leg of the AS device outward from the pivot point to increase anti-skate force. The weight on mine is all the way against the pivot, so I cannot decrease it any more. |
I don't have a JMW, but Tfkaudio's description of sonic murkiness with VPI's new AS device exactly mirrors what we hear if we set AS too high on our rig. Excess lateral pressure from the arm inhibits free movement in the cantilever/coil relationship, which dulls dynamics.
The solution is less AS, though how you'd implement that on a JMW is beyond me. Is there some way to put a lighter weight on the string or change the position of the fulcrum?
P.S. If you're using HFN&RR side 1/tracks 6-9 to set AS, don't just increase AS until you "pass" the highest track possible. That will result in AS being too high for real music. Skating force varies as the arm traverses the record, so using one (unrealistically dynamic) track located on the innermost grooves will skew your results.
A better way to set AS with that record is to equalize buzzing on the three widely-spaced "tracking test" tracks on side 2. This method achieves a reasonable compromise AS setting across the entire record.
The best way to set AS is to throw the HFN&RR record away. Do what Tfkaudio is doing: listen to music and adjust to maximize channel balance and center imaging while minimizing murkiness.
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The mechanical anti-skate has a thin piece of fishing line that attaches to arm opposite the one with the weight at the base. This arm has about five spaced indents meant to catch the fishing line so you can adjust the amount of anti-skate force being exerted. On my setup the fishing line is on the middle indent therefore providing about 50% of the amount of anti-skate available. Hope this makes sense. |
if you're having image problems it could very well be you need to play with azimuth on your arm. the jmw9 is sensitive to this. for the record, my image is rock solid center, although when i haven't it's always been an azimuth problem. |
Dodgealum, I'm not sure what you mean when you say "Installed with the wire located midway up the shaft...". Which wire? Which shaft?
Cheers. |
I went through the process with my Scout/Dyna 20XH and, like you, found that the wire twist was not enough to handle the HFNRR test disc, though I thought the table sounded just fine to my ear. But the neurotic audiophile that sometimes rears his ugly head caused me to get the mechanical system to see if it would allow clear sailing on the test disc and potentially cause the sound to improve. Installed with the wire located midway up the shaft my arm/cartridge now tracks all but the last groove beautifully (and even the last one buzzes only some). As to the sound--I really don't hear a difference. So......it was an interesting exercise that, to my ears, left me in the same place (unless I break out my test disc for some really great "tones"). |
I'm wondering if he was right when it came to 10 and 12 inch tonearms, but maybe not so much for 9 inch arms? 9 inch arms have a far more formidable anti-skate issue, due to the greater headshell offset.
I only need a little more anti-skate! I sound like a junky.
Can I put a JMW 10.5 on a Scoutmaster? How about a 12.5?
Cheers. |
My JMW 10.5 with a Decca Super Gold Mk VII on it traverses the first 3 of those fabled torture tracks without a murmur of distress, with VTF at 1.8g. And the Deccas are notorious mistrackers. The arm is standard, with only the wire twist to provide or affect anti-skating. I think Harry Weisfeld was right the first time. And I'll bet he thinks so too. |
Is your tonearm parallel or thereabouts to the record surface when your playing vinyl? |
Yes, I undid the lemo twist (sounds like a new dance craze). I even tried to counter the excessive force of the mechanical anti-skate with a clockwise twist of the lemo connector. It had no effect that I could notice.
As for tracking force, I'm currently tracking at 2.2g. The Dynavector DV-20 has a recommended range of 1.8g to 2.2g. Would you suggest going higher?
Thanks. |
Did you undo the first twist of the lemo before using the new contraption? The slight increase in antiskating force by the unfurled lemo could be exagerating that of the new device. VPI's explanation of why they use this method indicates that they found an increase in tracking force (with no antiskating force) improved the sound quality. I have also found this to be true even if it does burn up styli quicker. IF you have an uber expensive cart this is probably not a good option though.
Good luck! |