Spiral Groove Centroid tonearm



Anyone has any experience with this new design? It has a rather brief rave review along with the Spiral Groove turntable in the latest Stereophile. It seems like an exciting analog product in recent years, along with Thales arms. Allen Perkins is a respected designer and I am intrigued by his tonearm design and wants to learn more about it.

From what I read, it's a unipivot design with a unique counterweight and bearing housing that concentrate most of the mass at the center pivot point, hence the name Centroid. I am also curious about how it deals with azimuth rocking in a unipivot design. Does it have a secondary ball bearing to stabilize torsional behavior like the Graham Phantom, Basis Vector, and Continuum Coppperhead, or the slightly different Nottingham and Simon Yorke? Or is it a pure unipivot with a spike and dimple? In unipivot designs, it is how the designer handles the azimuth rocking that truly shows the creativity. I'm surprised this tonearm has garnered much talk among the forum lurkers. If you know more about it, please contribute and discuss. Thanks!

Some pictures.
hiho

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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Hello Glai,
It shouldn't be a big problem but it would have to be specific to your needs. The current RCA block on the SG Integrated mounts on the integrated Spiral Groove armboard and could not accommodate an XLR pair. The Universal Integrated version is designed to accommodate a lightly sprung turntable design so an integrated XLR block may not be feasible there either. Could a solution that included a longer tonearm wiring harness that terminates into an XLR termination box, which would mount separately from the armboard work for you? Maybe mounted directly on the back of the turntable or on a bracket of some sort that would then mount to the turntable? Or depending on your situation, a strain relief solution that mounts the XLR termination box to the shelf. Have to be very careful moving that one around though.... I'll check it out for you. Maybe you could email me at immediasound3@earthlink.net for a more specific conversation. Stirling
Has anyone used this table with the Ortofon A90? If so how did it preform on it?