Spiral Groove Centroid tonearm

The concept is that you pass the blunt end of a 1mm drill shaft through the Centroid headshell and also partly into the body of a Delos or Kleos. This will align the stylus of the Delos/Kleos where it needs to be in the Centroid.

Cool! I wish all cartridges and tonearms are standardized in such a way and would certainly save so much time for audiophiles.

Anyone else has more info regarding the arm design on features that Mosin pointed out such as its dynamic behavior, mass distribution, energy transfer, material, damping, pivot position, etc...? Mr. Perkins is a talented designer and I would like to learn more about his new creation as it, at least, appears to exhibit solid engineering and inventiveness.

From the look of it, I suspect the Centroid implemented some of the idea from his earlier design, the Immedia tonearm, which includes novel features like platter level pivot point with adjustable VTA at the bearing spike. The Centroid is probably a further refinement of the Immedia with new idea in handling inertia. Exciting! Also want to know if it uses a secondary bearing to stablize azimuth rocking.

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Thank you so much for the write up, Mr. Trayle. No apologies needed. That's the kind of info I was looking for and it couldn't be better. You managed to talk about all the design features without lapsing into even one sentence of pornographic sonic description. Bravo! You have no idea how sick I am reading reviews about how "neutral" or "musical" a device is without any analysis of its function and mechanics. Just for that, I applaud you.

The said alignment arrangement is a great idea and I wish more manufacturers can adopt that in the future and, hopefully, it can be standardized among cartridge and tonearm makers. ANYTHING getting the alignment close to the ballpark is better than nothing. All it takes is two tiny holes, one on the headshell and one on cartridge body. Hey, why not!

Thanks for the explanation on the centroid concept applying to the arm pivot. Does the arm still retain the design feature in the Immedia arm like adjusting VTA WITHOUT moving the pivot point? Judging by the picture, the set screw in the middle of the bearing housing appears like such mechanism. I always find that a very unique feature in the Immedia arm, even though the VTA obsessives might complain about the lack of on the fly adjustment - not surprisingly they are usually unipivot users because, I believe, typical (not all) unipivot arms inherently require mass below center of gravity to be stabilized and its pendulum effect can affect VTF, hence sensitive to VTA adjustment. The Centroid concept probably helps in that department. Does it have VTA on the fly adjustment, then? No big deal to me, I rather be listening to records than constantly fuzzing over VTA. Speaking adjustment, how is azimuth adjustment achieved? Another question is damping. Does it have fluid damping like the Immedia or any damping at all?

Don't worry about being promotional. I am sure prospective buyers are more than happy to find out all the design features than not. Your write up is professional, informative and, to me, educational. Thank you for your time.

I am tickled by the story that a bunch talented designers from competing manufacturers sitting around "chatting about things analog" and coming up with ideas that can benefit audiophiles "in the spirit of furthering the art and not market competition." It is this spirit I wish to see more in the forum world.

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Judging from Stereophile's brief review, the Centroid's design features apparently have been rewarded in sonic terms; two distinct positive characteristics are low noise floor and accurate deep bass. Here's what Brian Damkroger has to say in the review in June 2010 issue.

"As I listened more, the characteristics that made the Centroid sound so different became obvious. First and foremost, it had no noise floor - not a dramatically reduced noise floor, but NO noise floor.... A second distinct and obvious characteristic of the Centroid's performance, and one new to me, was how accurately it reproduced the tonal and dynamic elements of deep bass notes."

Unipivot arms tend to sound quiet to me so I am not surprised, especially since the Centroid opted for a classic unipivot design with no secondary bearings (the chance of bearing chatter). And quality deep bass is something new in the unipivot genre as it traditionally have a less impactful bass due to the azimuth instability so I have to guess the centroid concept overcomes that. Very promising indeed.

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Pictures of Centroid for entertainment purpose:

Spiral Groove Centroid 1

Spiral Groove Centroid 2

Spiral Groove Centroid 3

Spiral Groove Centroid 4

Spiral Groove Centroid 5

Spiral Groove Centroid 6

Spiral Groove Centroid 7

Spiral Groove Centroid 8

Spiral Groove Centroid 9

Centroid YouTube videos

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