Agree with all the above. Adjusting VTA is essential, and the Expressimo collar is my favorite of the ones I've seen so far. I think jphii ordered one of the adjusters Colitas saw on ebay. Maybe he'll report.
Check out this thread for a detailed discussion of setting VTA for different records. It's about more than just thickness:
http://forum.audiogon.com/cgi-bin/fr.pl?eanlg&1081349573&read&3&4&
Also, check the Walker website for a superb explanation of how to set VTA and VTF by ear (the only way). These two adjustments are interactive and must be set together to get the most from your rig.
Check out this thread for a detailed discussion of setting VTA for different records. It's about more than just thickness:
http://forum.audiogon.com/cgi-bin/fr.pl?eanlg&1081349573&read&3&4&
Also, check the Walker website for a superb explanation of how to set VTA and VTF by ear (the only way). These two adjustments are interactive and must be set together to get the most from your rig.