Reed 5T Opinions

@molly , Incredible rig molly. That is my favorite turntable. I am waiting patiently until it is offered with a vacuum platter which Dohmann has said is coming along. I did not know the 5A had been released. For those who do not know what it is, it is a manual version of the 5T using the same geometric trick but with clever bearing management instead of lasers and motors. The Schroder LT is another manual arm that uses the same trick. All three arms are not offset (they are straight) remain tangent to the groove within a fraction of a degree and do not require anti skating. What the arms are doing is using the frictional pull of the record on the stylus to drive the mechanism of the arms. Normally this friction just generates heat. 

Good luck with your table. I'm jealous!  

For those who have not heard the term, Zenith Error it is a new factor that Wally Tools has jumped on. Zenith error is a rotational error of the stylus. If you were looking down on the tip of the stylus the long axis of the stylus is not perpendicular to the groove. To correct it you would have to rotate the cartridge. In order to measure it you need a good microscope which Wally Tools will also sell you. Of course if your cartridge is built correctly you do not need any of it. You can see well enough with a decent and inexpensive USB microscope. The two cartridges I currently have, a Soundsmith and a Clearaudio are good enough that I can not see any zenith error. 

The Wallytools person I spoke to at a show said thar the $1250 microscope is used primarily to set VTA/SRA but that it is not useful for reading zenith. For that, you send your cartridge to them and they use an ultra expensive microscope and give you the zenith correction which you can make with another tool of theirs.  The representative said that none of the big makers of styli currently do a good job of accurately mounting styli as far as zenith is concerned, but they have said that they will look into this now that they have been shown data on this issue.  

I saw the 5T at a show.  The base looks like it is too large for my Basis Debut.  What a relief, I won’t be tempted.  It is a thing of beauty, and the engineering appears to account for and mitigate all of the shortcomings of linear tracking design (except cost).  It works on the same principle as the Shroeder LT arm, except the rotating base is powered by a motor controlled by a laser sensor whereas the LT base moves from the drag of the stylus playing the groove and is controlled by magnets.  I wonder how these two arms compare in performance.

"Normally this friction just generates heat." ...and the skating force in a conventional pivoted tonearm.

The term "zenith" seems to have been re-invented for our particular obsession.  If you look it up, there is no dictionary definition that fits Mijostyn's definition, but I think he got it right as it now applies to vinyl reproduction.  A friend who is well known in the industry has been looking closely at zenith for typical cartridges and typical alignments.  As I understand his messages to me, he finds that almost never is it perfectly right.  We are all living with bad zenith.  BAD, I tell you!

Sounds like the Reed 5A is somewhat like the Swiss Thales.  It just stands to reason that the complex bearing structure, no matter how beautifully wrought, must generate friction.  It remains to be seen how or whether that affects SQ.  Based on Molly's testimony probably not much if at all.

The 5a is based on a design like the Thales arm and so it has additional pivots to locate the arm.  That is not the case with the 5T.  With the 5T the arm’s motion is only restricted by conventional pivots.  When the arm is slightly out of tangent, a laser beam and sensor detects this condition and a servo motor slowly rotates base that the arm is on to reestablish proper geometry.  Other designs have used optical sensors and servos (like the B&O Beogram 4000), but, the slow rotation of the arm base is supposedly smoother and less likely to cause vibration.