Variations of the Micro Seiki MA505 tonearm

Thanks for the informative responses. Just to be clear, tho, the sample I own is a MkIII with a removable straight arm tube. Since it is of this late type, can it utilize the optional azimuth-adjustable headshell that you (Thom) describe? On earlier versions of the arm, with the S-shaped tube, I can clearly see in photos that the headshell is detachable; moreover it is of a different shape and size compared to the miniscule head shell on my MkIII arm tube. On the MkIII it does not appear that the headshell is meant to be interchangeable. I was also interested to read Thom's declaration that none of the 505's do VTA on the fly. Mine certainly does not, in agreement with what Thom wrote, but others that have been for sale are often described as having this feature. In photos, it looks like you can twist the stem that attaches to the locking collar to obtain a minimal up or down movement of the pillar without entirely loosening the grip, on non-MkIII versions. On the MkIII, the stem is a single solid piece that can only be used as a lever to loosen the collar entirely. Anyway, it's a beautifully made piece of gear, and I am happy to own it.

Dear Clio09, Your description appears to be correct based on photos of the early versions of the 505 found in Micro Seiki publications and on-line in For Sale ads. Looks like, as you say, you can twist the knurled knob at the end of the stalk that projects out from the locking collar for the arm post, so as to be able to adjust the height up or down by a few mm's at least without fear that the arm will come completely loose and fall to its base setting. My MkIII does not have that capability. Maybe MS thought this was an unsafe feature and therefore delete it from the MkIII.

Thanks for your input, Thom. Since the VTA is easily adjusted, though not "on the fly", I have no complaint. I do however wish there were a mechanical adjustment for azimuth. I guess I am spoiled by my long term experience with the Wheaton Triplanar.

Clio09, I too considered the possibility that I could adjust azimuth simply by twisting the arm tube where it mates to the rear portion of the mechanism, but alas that does not work. The arm tube needs to be fixed in place by tightening down on a knurled screw; with that screw loose (if you'll pardon the expression) you can wiggle the arm tube a little bit, but you are putting stress on the stationary male contact pins that reside within the rear mechanism. Not a good idea at all. The headshell seems to be held in place by tiny screws under the end of the arm tube. My one last hope is that one can twist the headshell a bit when those screws are loose, but I strongly doubt it.