Expressimo RB 250 mistracking issue

Problems like the one described by Maktheknife happen with some frequency on certain Rega arms. I've seen several posts like his over the years.

The fact that yours is mistracking on only the most challenging LP's may simply indicate that the wire or insulation is out of position by only a small amount, so that the pressure it's applying is small. This might indeed cause audible mistracking on only the most challenging passages. If you read his post again you'll see that's just the symptom he had, "All of a sudden SOME of my ... LP's began skipping".

It can't hurt to check the routing of your tonearm wire and its condition. While you're at it, dismount and remount the cartridge from scratch - just to make sure everything is still set up properly.

Mistracking is just a skip that didn't quite make the jump into the next groove. We're talking about differences in degree, not in kind, so any possible explanations apply to both.

I haven't had a Rega style arm for several years (and never had this problem when I did) so I can't advise specifically on where to look. In general, check where the arm wire exits the arm wand and moves past the bearing. Check it at all points across the arm's arc of travel for any pressure or binding. Perhaps Maktheknife or another Rega owner can be more specific.

Good job that you remounted the cartridge. You said your stylus is clean. May I ask what you've been using to maintain it, and how often? I have rehabilitated over a dozen supposedly faulty cartridges costing from $300 to over $5,000 simply by cleaning the stylus properly. The owners all claimed they had done so, but their methods proved to be inadequate.

Just fishin' for ideas that might help...

Doug

P.S. Have you changed or altered your phono stage since these tough LP's last played cleanly?

Zerodust and a dry brush are not adequate for long term stylus cleaning. Many of the cartridges I've rehabilitated, as discussed above, were maintained using exactly that.

Do a search here or on Vinyl Asylum for "Magic Eraser" or click "Threads" beneath my signature, or PM me and I'll send you a document if you like.

I asked about phono stage changes because "mistracking" sounds on dynamic peaks are often not mistracking at all. The identical distortions can be caused by phono stage overload. Since yours hasn't changed, however, that explanation seems unlikely.