Alignment Snafu? Or?

Ted,

You're more likely to be able to align a cartridge at the Baerwald points on an OL arm if you mount the arm somewhat closer than the specified 223mm. The problem with 223mm is that, (i) Rega/OL arms were not designed for Baerwald and, (ii) at OL's specified 223mm mounting distance most cartridges will be very near the ends of the headshell slots and some won't align properly even when slid all the way forward.

Here's what I'd do:

1. Mount the arm at 222 (the Rega-specified distance, which is presumably what Wally scribed his Rega arc for);

2. Mount the cartridge and see if you can get the stylus to hit the arc at all points by moving the cartridge forward or back in the headshell;

3. If you can trace the arc, bingo. Square it up on the alignment grids and your're done.

4. If you can't trace the arc, even with the cartridge all the way forward, you'll need to choose another arc and another mounting distance.

G'luck,
Doug

Ted,

Forgot to mention. With an OL at 222m, aligning a cartridge at the Baerwald points will leave it slightly angled (inward) in the headshell. That's okay - as long as the stylus is tracing the arc and aligned on the grids.

Thanks . I'm assuming the general principle is to have the stylus track the (in this case 239mm ) arc somewhat irrespective of the exact manufacturers specified distances. This would imply that other arcs are equally acceptable if possible, limited only by the design of the arm/headshell/cartridge.

Part Deux,I went on today to check my mint Denon DP-2550, with Grace DA-307 Arm, S-P distance supposed to be 230mm, and evidently, the previous numb nuts mounted the Arm at 221mm Way off.

The furthest I can mount the Arm is at 228mm, so I have contacted ken, and see if a Protractor at 228mm, with nullpoints at 57.9mm/114.6mm is doable?

Not Baerwald, or Stevenson, but hopefully this will be the ticket to good sound from this very nice Table.
This is my "Quad Baby", set up with new AT-15S, and a NOS in box AT-20SLa on ice.

Just bought a spare AT20SS Stylus from LP Gear for the AT-20SLa, and understand it will fit the AT-15S as well. Ultra "skinny" Beryllium Cantilever! Looks beautiful!

Also grabbed one of those Black Nitrile "Tranquility" Belts for my VPI 19 Table, will put it on tonight, and give a listen with the ZYX Airy 3X. I'll probably be in the police logs tomorrow! Mark

Ted,

Correct assumption.

Mark,

Null points at 57.9/114.6 aren't necessary, and probably not optimal unless you have many LPs with very wide lead-in grooves (like 1/2" wide) and music cut right up to the label. Not very likely, so I don't understand why anyone would choose those weirdly positioned null points. They'll result in very high distortion on the first track and higher than necessary distortion in the middle.

If it were me I'd ask him for an arc designed for the Grace mounted at 228 with Baerwald null points.