Triplanar Problem

Thanks to Everyone - Some great (and sensible advice) Armrest appears to be exactly as should be - with a slight dogleg away from platter.

The Avid Armboard is at fault - I think the Triplanar holes are in wrong position (spot on with 2b Doug) - Its an "add on" that's bolted to Acutus subchassis (using 4 already predrilled holes for an SME) - then Triplanar attached to 3 holes in armboard - I'd expect Triplanar to sit perfectly in centre of armboard - on closer inspection - its off centre. Using Jig (whether accurate or off) is almost superfluous - I'm relying on Correct S-to-P measurement etc via Avids' predrilled Armboard - there's no way of redrilling anything.I've dismounted arm and armboard is packed up ready to send back so can't check S-to-P measurement (but will be the first thing I'll check with new armboard)

Have spoken with dealer and am awaiting response (and hopefully a New Armboard) Hoping it's this and nothing's wrong with Triplanar geometry. Haven't touched Triplanar itself (bolt underneath etc) - I hope it doesn't need to go back to Tri as a) I'm desperate to play some vinyl (CD player sold a long time ago)and b) It'll have to travel back to US a second time in a month
:-(

It's really frustrating - All appropriate Viton O rings bought, new Discovery cable with XLR's, Yip's Mint Protactor for Acutus/ Triplanar waiting to go - Arrgghh!

As a quick aside - Conrad never rated Triplanar on his Acutus (no idea why - He's always used SME's) - IF (a big If) I was to change TT - what would you suggest? Remember ,I'm in UK and now that the GB pound has nosedived against the US Dollar (Galibiers, Teres etc are therefore out)seems to make sense to buy a TT from this side of the pond. Would you rate better synergy with TP/Uni on an Amazon Ref or an AC Raven? Anything else to consider?

Thanks V Much (Especially Doug - The TP Jedi Master!)

Jonathan

I want to expand on Doug's point 2a, which is the reason why I require Galibier purchasers to send their Tri-Planars to me in order to drill their armboard.

The Tri-Planar (like the Schroeder Reference), has an arm mount that is concentric with the VTA tower. The VTA tower is offset from the arm's bearing pivot point, so any fine rotation of the arm's mounting orientation (the three holes) will change the pivot to spindle distance.

With Galibiers (unlike fixed mount turntables) getting the correct pivot to spindle distance isn't a problem because one can rotate the armboard to bring it back into spec. I do however want too ensure, is that the Tri-Planar is nicely oriented when it is parked in its armrest, and if I rotate my armboards to bring the pivot to spindle into spec, there's a possibility of making the mount look a bit "ungainly". I like the arm to point front to back, which is not only aesthetic, but also provides a reasonable amount of clearance between the headshell and the platter.

Doug's bet on 2b (bad mounting jig) is one possibility. There is another more probable one. In the end, it doesn't matter because the solution is the same.

When a Tri-Planar is assembled, a large straight-slotted screw on the under side of the VTA tower is torqued to spec . There's a remote possibility of a couple of degrees of slippage (rotation of the mounting flange) when this screw is torqued to its final specification. This would lead you to believe that the jig is wrong.

Any jig made for a Tri-Planar presumes that the mounting flange is oriented perfectly, and I would NOT bet on this.

I think a more accurate statement about the mounting jig is that they are not consistent with the rotational orientation of 100% of the Tri-Planars in the field. There may have been several generational drawings of this jig based on different samples of Tri-Planars (mounting flange orientation), and you could call any of them right ... or wrong.

My point is that even the metal jig should not be trusted, because of sample to sample variance in the mounting flange's orientation. Don't waste your money on the metal jig. You are still advised to follow the procedure I lay out below, using any jig as a STARTING point only.

Whether you have a "bad" jig or a mounting flange that is at variance with the jig can be argued about until the cows come home, but the solution is the same - forget about the jig and use your trusty ruler. I created my own Galibier specific mounting jig before understanding this idiosyncrasy, and my mounting technique is identical to how I'd mount the arm with using the supplied jig:

This is an imperfect world, and even Doug's and my tonearm of choice has its quirks. Doug and I make an effort to work you through the Tri-Planar's these idiosyncrasies. As an aside, I maintain a quite a few information pages on the Tri-Planar section of my website. Periodically, I try to link to Doug's generous contributions to this forum as well.

Given that you shouldn't mess with the bolt under the VTA tower, the solution is indeed a re-mount. On this, we all agree.

1. Mark all three holes using the jig, but DON'T drill anything.
2. Locate the arm over the three holes you've marked and observe: (a) the pivot to spindle distance (should be 233.5mm) and (b) how the arm is oriented when locked in the arm rest (you should like how it's oriented and ensure that it clears any dust covers, etc.). Note - you may need a third hand (either human or a soft jawed clamp of some sort) in order to hold the arm in place while measuring.
3. Once you've arrived at a nice position for the arm, center punch, drill (and tap as necessary) ONE hole - the one on the left (closest to the platter).
4. Mount the arm by this one hole, and perform fine measurements, rotating the arm around this one point in order to achieve the 233.5mm pivot to spindle distance.
5. Mark the remaining two holes
6. Remove the arm, center punch, drill (and tap if necessary), the remaining two holes
7. Mount the arm
8. Use the slight bit of intentional play in the mounting holes to bring the pivot to spindle distance to a perfect 233.5mm

Note - if you're using an arc-style alignment protractor, then wait for your cartridge alignment step to perform step #8.

Cheers,
Thom @ Galibier

Thom,

That was one of the clearest, best written and most helpful posts I've ever seen. Thanks for so generously sharing the results of your experience mounting different TriPlanars.

You provided a simple and sensible procedure that will work in all but extreme cases of inaccuracy, regardless of whether the inaccuracy results from the jig or from rotation of the mounting plate during tonearm assembly.

I'd suggest adding a generic version of this post onto the "TriPlanar Tips" thread and/or your website. This information is so helpful it ought to be where other TP users will find it.

Jonathon,
I'd recommend sharing Thom's post with your dealer and/or Avid. This would let them understand the issues and position your three mounting holes correctly while also helping them prepare for future TriPlanar armboard requests.

As to AC Raven or Amazon Ref, it's unlikely there'll be any synergy advantages or disadvantages between the TriPlanar and either of those two tables. Aside from fit-up challenges like the one you're dealing with now, table/arm synergy is rarely a major issue IME and will not be with either of those tables. I've heard TriPlanars on both and there were no problems.

In respect of fitting, the Raven's rotating armboard (like my Teres and Thom's tables) offers some insurance that you can easily attain a correct setup. Most owners who have this feature quickly wonder how they lived without it.

Both tables are made with the kind of precise, solid engineering you're accustomed to from your SME. Beautiful stuff.

The Raven's more massive platter and less elastic belt make it a bit more solid in the bass and clear on transients, though it won't quite match a non-elastic belt driven Galibier or Teres in this respect. The Ref's lighter platter and more elastic belt provide a slightly more relaxed presentation. Which you prefer is up to you of course.

Gentlemen,

This all seems to be much ado because of a template design that really isn't the best possible for the application. I'm am certainly not saying that Herb Papier didn't design an absolutely wonderful tonearm, or that Tre didn't carry the design to the highest level, because they obviously did exactly that. However, maybe the setup tool can be improved. Jim Winey of Magnepan fame made a tonearm which also has on-the-fly VTA with the post in a place other than the pivot point. I don't see why such a design couldn't be adapted to work with the Tri-Planar. It is a two-piece pivoting affair that allows the user to actually see the result before the mounting hole is drilled. Not only does it work satisfactorily, it gives perfect Baerwald alignment results every time. Additionally, it reduces the tonearm mounting task to a matter of maybe fifteen minutes for most turntables, including drilling the hole. Maybe someone should take a look at it because there are things to be learned from history.

http://www.vinylengine.com/library/magnepan/unitrac-1.shtml

Hi Moisin,

However, maybe the setup tool can be improved.

I'm thinking out loud here ...

My first thought when I read your comments was that the mounting collar alignment needs to be perfected (either by use of some sort of assembly jig or by keying the two parts to each other).

As I thought about this more (and considered the reality of manufacturing), my thoughts turned toward a universal jig that would accomplish the mounting task elegantly while having the advantage of being compatible with all arms in the field.

This would be a two-part "jig" for setup - one that mirrors the process I lay out above. It would consist of:

(1) the existing jig with only one hole - to ensure that the above method I outline is followed
(2) some sort of trammel affair (think Feickert) that allows you to rotate the arm into position and measure the 233.5 p-s distance - this, after temporarily fitting the arm to the armboard with the single screw.

While a trammel affair has its appeal, it's not inexpensive to manufacture, as you need to account for varying record spindle diameters.

If you bore a spindle hole for a large record spindle diameter (e.g. .287"), then the trammel will tilt when used with the more average record spindle diameters (e.g. .280-.282).

One solution is to produce a wide base plate for the spindle hole. This would prevent the trammel from tilting. Unfortunately, once you add material like this, the costs skyrocket, and frankly, the method I propose above will work fine.

I think a part of this discussion involves working with a competent dealer (hate to blow my horn here, but picking up after the incompetents out there tries my patience). There's still a reason for going to a competent dealer for your setup.

For those doing their own mounting, I think a good interim solution is to remove two of the holes in the existing jig, and to follow the instructions I outline above. Having only one hole in the jig would ensure that someone doesn't blindly mark and drill all three holes at once.

I'll get a version of the above discussion on the Tri-Planar page Doug. Thanks for the kind words.

Cheers,
Thom @ Galibier