First impression of the Dual Pivot Kit

First impression of the Dual Pivot Kit

Postby Peer Gynt » Tue Jul 31, 2018 11:07 pm

I’ve whined about the aggravation of setting up the unipivot a bit. I do not find it to be as simple as a well designed gimbal.

Naturally, this means that I’m a good candidate to try the Dual Pivot Kit. So I have. I ordered one from an internet supplier a few weeks ago, and last night when I was changing cartridges on the JMW 10 3D Printed tonearm, I installed it. I got distracted with another project, and did not finish the set up until tonight.

It was a bit easier ... but still not as easy for me as the gimbal style with screw driven counterweight.

With that said, I acknowledge that the Dual Pivot is a good upgrade. I have been auditioning it using an album that I’ve always considered inferior and expendable- Anna Netrebko: Verismo. I’ve never really thought this was very good, so if the set up was potentially damaging, the loss wouldn’t bother me.

A surprise to me has been just how engaging and musically interesting this album is proving to be during this audition. Something about it is brought out by this new retrieval configuration.

Two general thoughts. First, the Dual Pivot had a large effect on antiskating. I have loaded it very lightly, but there must be enough friction force to offset the bias force. Using Peter Lederman’s method of setting anti-bias so that it isn’t quite enough to overcome bias in the lead out groove, I basically ended up disconnecting the rocker system and “going commando.”

Second, the place where the unipivot or dual pivot augmented unipivot could beat a gimbal would be where azimuth was not square to the cartridge body so that azimuth alignment were necessary.

I am pretty old school on all these adjustments. Dealing with Linn, if the stylus were skewed relative to its nominal position, it would be called a defect. Linn make no provision for such alignment.

I’ve had a lot of cartridges over the 50+ years I’ve been in this hobby, and maybe I’ve had cartridges that needed this sort of alignment capability, but really, the only time I’ve ever done this alignment was when I had to due to the lack of a fixed headshell geometry.

So ... I see this fozgometer alignment and VTA setting stuff as interesting and possibly useful capabilities to fix something that’s not right. But I have never missed having either one. You can drive yourself nuts trying to find 1 or 2 degree improvements. I know ... that’s part of the fun.

Meanwhile, back at the audition, this is a far more beautiful recording than I’d remembered. The Dual Pivot Kit must be doing something good.
Last edited by Peer Gynt on Wed Aug 01, 2018 1:23 pm, edited 2 times in total.
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Re: First impression of the Dual Pivot Kit

Postby Stringreen » Wed Aug 01, 2018 12:00 am

When I installed the 2nd pivot on my 3D10, I was amazed on how much better it is than without. I recommend the Fozgometer and its accompanying record....its quite easy to lock in perfect azimuth with a corresponding opening of the soundstage.
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Re: First impression of the Dual Pivot Kit

Postby Johnny » Wed Aug 01, 2018 7:19 am

Peer Gynt, thanks for posting your impressions of the dual pivot.

I agree with PG that it will take some time and effort to set the dual pivot up correctly, but the effort will be rewarded with improved performance. IMHO and experience, the dual pivot has become a must have for the VPI uni-pivot tonearms. If I was going to make a suggestion to VPI, I would incorporate the dual pivot into the azimuth ring (like the first protoypes) and make the dual pivot a regular production feature.
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Re: First impression of the Dual Pivot Kit

Postby Brf » Wed Aug 01, 2018 8:32 am

Peer Gynt, very nice detailed write up. Thanks for posting!
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Re: First impression of the Dual Pivot Kit

Postby Peer Gynt » Wed Aug 01, 2018 10:25 am

Johnny wrote:Peer Gynt, thanks for posting your impressions of the dual pivot.

I agree with PG that it will take some time and effort to set the dual pivot up correctly, but the effort will be rewarded with improved performance. IMHO and experience, the dual pivot has become a must have for the VPI uni-pivot tonearms. If I was going to make a suggestion to VPI, I would incorporate the dual pivot into the azimuth ring (like the first protoypes) and make the dual pivot a regular production feature.


I really agree. The only downside that I can see with the dual pivot is that it looks like $20 worth of parts, but it costs $150. I suspect that this is largely due to the small production run. How many could they need to make?

I think it’s included with the unipivot Fatboy, and if it is, that’s a good thing.

Meanwhile, if you’re the sort of listener who does want to use the Fozgometer, a Dual Pivot modified Unipivot may be better for you than a gimbal.
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Re: First impression of the Dual Pivot Kit

Postby Golear » Wed Aug 01, 2018 11:43 am

Thanks Peer Gynt.

Just so that I understand fully, could you confirm the following:

1. The Dual Pivot adds some drag to the rotation of the tonearm.
2. This drag led you to disconnect the mechanical anti-skate.

Also, is there any twist in the tonearm wire?
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Re: First impression of the Dual Pivot Kit

Postby Peer Gynt » Wed Aug 01, 2018 12:12 pm

Golear wrote:Thanks Peer Gynt.

Just so that I understand fully, could you confirm the following:

1. The Dual Pivot adds some drag to the rotation of the tonearm.
2. This drag led you to disconnect the mechanical anti-skate.

Also, is there any twist in the tonearm wire?


1&2 ... yes

No twist.

I am using Peter Lederman’s approach, which he attributes to a German colleague whose name is not on the tip of my tongue.

You drop the needle in the unrecorded end space, and if anti-skate is good, the arm will slowly move toward the spindle until it gets picked up in the groove.

I set the dual pivot up with very minimal preload. The side weights are fully retracted. I got the dual pivot foot to the right height necessary for headshell parallel to the vinyl. I went to set anti-skate by fixing the monofilament to the rocker, but it was excessive ... after a needle drop into the dead zone, the tone arm wanted to slowly move away from the spindle before it was caught by the spiral.

So I removed washers successively, but I continued to see the antiskate slightly overwhelming the skate.

So I pulled the LEMO to be sure it wasn’t twisted (I’d not intended it to be twisted), and it was not.

I then disconnected the monofilament, and found that the drag from the dual pivot point on the mirror was enough to give me Mr. Lederman’s desired result.

YMMV. Note that antiskate needs are related to stylus profile and and set up.

If I decide to add antiskate after extended listening, I will probably try a twist of the LEMO bundle as the first change. I’ll know better after more listening.

With the unipivot and an eccentric counterweight, you can get dual pivot preloading just from cartridge weight or counterweight rotation (intended or unintended). I was shooting for minimal counterweight contribution and no side weight contribution to the preload.

FWIW, I was surprised at how little of the dual pivot point was projected out of the “housing”.

Other observations about VPI antiskate - HW advised me that if I needed the rocker, to set it up so that it would be just engaged at the lead in groove, and that the washer laden rocker would be horizontal at the lead out groove.

Add washers to achieve more antiskate. Remove washers to achieve less.

I had to slightly lengthen my monofilament to achieve this. I needed to have the rocker engaged with three rubber washers present before the dual pivot was installed.
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Re: First impression of the Dual Pivot Kit

Postby Jprod » Wed Aug 01, 2018 12:16 pm

As a newbie and not handy I am always hesitant to modify my tt. What was difficult about the installation?
Any tips?
VPI Prime with ortofon 2m black, Manley Chinook phono preamp, Wyred4sound STP-SE preamp, parasound halo a21 amp, Ascend acoustics tower speakers with RAAL ribbon tweeters, audio sensibility signature cables
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Re: First impression of the Dual Pivot Kit

Postby Peer Gynt » Wed Aug 01, 2018 12:55 pm

Jprod wrote:As a newbie and not handy I am always hesitant to modify my tt. What was difficult about the installation?
Any tips?


There wasn’t really anything that I would characterize as difficult. Cartridge setup is more tedious than difficult.

Some general advice:

Keep that stylus and cantilever in the front of your mind. Whenever possible, keep the stylus guard in place. When you have to remove the arm for a new trial and error adjustment, put the guard back on.

When you are fiddling with the back end of a unipivot, be ever mindful of the fact that it is designed to support a relatively small, vertical load. Don’t try to use it as a ground for the force you apply to move your sliding counterweight. If you do, you may deform it.

The dual pivot load bearing plate will limit how close to the bell you can move the counterweight. The 140 gram counterweight worked well with the 8.8 gram cartridge. The 160 gram counterweight would have interfered.

I removed the arm several times to make adjustments to the dual pivot foot and to the tracking force. Of course it also took a few iterations to get the overhang to match the template.

I think I could learn to do these fast if I were in the business. When you consider that you will probably listen for 1000 hours before you have to have the cartridge retipped, the set up time is a small investment.

Having the dual pivot was definitely easier than winging it with the wing weights.

I felt like I had an excellent setup (and sound) without the dual pivot, but since others felt that the dual pivot was a sonic upgrade, I decided to try it with the cartridge renstallation. I’m glad I did. My sense is that I am hearing more of the recording environment. There is more space around performers and more detail is evident.

Overall though, I’m really strongly attracted to the gimbal version of the Fatboy, and I’d like to step up to 12” at the same time. That means another table ... ah, the silver lining I’ve been looking for. :roll:
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Re: First impression of the Dual Pivot Kit

Postby Jprod » Wed Aug 01, 2018 1:12 pm

Thanks for the detailed response!
VPI Prime with ortofon 2m black, Manley Chinook phono preamp, Wyred4sound STP-SE preamp, parasound halo a21 amp, Ascend acoustics tower speakers with RAAL ribbon tweeters, audio sensibility signature cables
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