TriPlanar Tips


The manual that comes with the TriPlanar Mk VII tonearm is fairly complete, but there are a few things I’ve learned only by living with the arm. Note: I do not know which if any of these would apply to previous versions of the arm. My only experience is with the Mk VII.

1. NEVER raise the cueing lever while the arm is locked in the arm rest. This pressures the damping cylinder and could cause a silicone leak. For this reason and also for safety, whenever the arm is in the arm rest the cueing lever should be DOWN. This is backwards from most arms and takes some getting used to.

2. If your Tri-Planar doesn't cue straight down there's a quick fix, which may be included on some new arms. The problem is insufficient friction between the arm tube and the hard rubber cueing support bar. Just glue a bit of thin sandpaper to the underside of the arm tube. Make it big enough and position it so it hits the cueing support bar at all points across the arm’s arc. (Note: after doing this you will need to adjust the cueing height, see Tip #3.)

3. When adjusting cueing height (instructions are in the manual) always do so with the arm in the UP position. This adjustment is VERY touchy, since the cueing support bar is so close to the pivot. Be patient and be careful of your cartridge. (Note: after doing this you may need to adjust the anti-skate initiation point, see Tip #4.)

Chris Brady of Teres told me of a way to improve cueing even more by re-shaping the cueing support. Moving the cueing support point farther from the pivot improves its mechanical advantage and makes the cueing height and speed adjustments less touchy. This mod is easier than it sounds and requires only a length of coat hanger (!), but I don’t have pix and haven’t yet done it myself.

4. Changing the cueing height affects the point where anti-skate kicks in. (Yes, it's weird.) Once cueing height is satisfactory, adjust the short pin that sticks out of the front of the cueing frame. That pin controls where the anti-skate dogleg first engages the knot on the string.

5. The Tri-Planar comes with three counterweight donuts of differing masses. Many cartridges can be balanced using either of two. The arm usually tracks best with the heaviest donut that will work, mounted closer to the pivot. Of course this also reduces effective mass, which may or may not be sonically desirable depending on the cartridge. It also leaves more room for Tip #6.

6. For fine VTF adjustments don’t futz with the counterweight, there’s an easier way. Set the counterweight for the highest VTF you think you’ll need (ie, close to the pivot). Pick up some 1/4" I.D. O-rings from Home Depot. To reduce VTF a bit just slip an O-ring or two on the end stub. Thin O-rings reduce VTF by .01-.02g, thick ones by .04-.05g. Quick, cheap, effective. (For safety, always lock the arm down while adding or removing O-rings.)

7. When adjusting VTA, always bring the pointer to the setting you want by turning it counter-clockwise at least ¼ of a turn. This brings the arm UP to the spot you've selected, which takes up the slop in the threads. You can easily feel this happening.

Hope someone finds these useful. If you know any more, please bring ‘em on!
dougdeacon
agree on quick phone call to Tri
he has been very responsive to my questions re Mk7 u2

thanks for posting, while I dont mess w VTA much, I would also like to know..
So moving 2 whole number increments (~5 mm) changes the arm angle a little more than 1 degree (~..6mm more.) The pivot to stylus tip distance will vary depending on cartridge.

Did I get this right?
@jtimothya  Looks like it to me. A more effective method would be to vary the angle of the cartridge in the headshell, but there's no good way to do that and the VTA tower does it pretty well anyway. The only fiddly bit that isn't worked out is that as you vary the VTA tower, the overhang will vary somewhat as well. A tiny bit compared to the resulting rake angle...
In case its not mentioned earlier though, one issue is that while 92 degrees is a nice central point to set the stylus rake angle, almost any LP is going to be slightly different than that on account of the actual stylus used to cut the groove. Mastering engineers don't set for 92 degrees, they set for the lowest noise in the groove, which may or may not be 92 degrees.


@jtimothya  Looks like it to me.

Thank you Ralph.  Yes, SRA, VTF, azimuth, overhang - one can iterate 'til the cows come home.  This was as much an exercise of curiousity and to get a sense of how much range do I have with the Tri-Planar with the arm level for a given cartridge height.  I've given up using a scope to get to 92 degrees and went back to my ears.  On a normal day thin, medium and thick.is fine-grained enough.