Rega tonearm cartridge mount face

[Primalsea]

The face that the cartridge mounts to on my Rega RB250 is not parallel to the platter surface. I have to shim my cartridge. Has anyone else noticed this?


I think that Michelle mill the face of their modified RB250s and I guess it is to fix this and I wonder if in other Rega tonearms further up the ladder this is addressed, which would make them sound different, if not better.

Everything else in my tonearm is aligned, so I am sure it is just the mounting face that is out.

[walpurgis]

There's no harm in using a rigid shim. It adds a little mass, but in Rega arms many cartridges benefit from this.

[Chris]

Not sure if it is the head shell underside or perhaps the base/armboard interface itself as has always been the case with my Ittok LVIII. I use a “washer” made out of a piece of old credit card with a hole punched out, under the right hand arm base bolt between arm base and arm board to improve azimuth. Certainly improved central imaging. In the case of a Rega arm with a single nut to tighten you would have to wedge it under somehow

[Primalsea]

I had a search online and apparently I am not the only person to have noticed this. It seems so far people have noticed the issue on RB2XX &RB3XX arms.

[karma67]

to be 100% sure as already mentioned check the arm board is level to the platter and also cheek the platter is level with the mat off.

[hifi_dave]

If it is out of alignment, it isn't normal, as I have fitted tens of thousands of cartridges to RB tonearms since 1983 and never once had this issue.

You need to check as Jamie suggests and also check your cartridge is nice and square all round.

[Primalsea]

I think I have tracked down the issue. The yoke does not appear to be perpendicular to the bearing housing fork. I wll have to strip it down and see what’s what. The yolk is press-fitted in I believe and I am not exactly sure what I can do.

[Primalsea]

Took the arm off and checked everything again. Turns out its the bearing fork that is out. One “prong” is slightly higher than the other and therefore the same too for the holes that the bearings sit in. Only a fraction of a MM, but enough to be noticeable if you place a rule across the platter . Shame it sits higher spindle side as if it was the other way I wouldnt be too concerned because it would have countered the slight central depression in the platter a little.



Not much I can do really. I’ve had the arm for around 16 years, maybe I deserve a new one...

[walpurgis]

Unless the arm has been damaged, that sounds like it may be a manufacturing defect. Even after this amount of time it may be worth speaking to Rega about it.