Originally Posted by
Barry
Alex,
Can we run through all the checks you have made:
[1] Is the turntable level, especially the platter?
[2] Is the arm mounting collar and horizontal bearing housing vertical with respect to the platter?
[3] Is the VTF as recommended by Ortofon, or at least not less than the minimum of the recommended range? (I always start with a setting 0.25g below the maximum recommended figure and work from there.)
[4] Do you still have problems if the bias dial is turned to zero?
[5] Is the azimuth correct? (you can use a mirror to check this.)
I still think the problem is with the arm applying too much bias. In my experience the bias calibration on most arms, marked as being appropriate for a given tracking force, are only correct for spherical stylii, for others: elliptical; fine line etc., the bias setting need only be half that of the corresponding playing weight (VTF).
Thanks Barry, here are the vital stats:
[1] Is the turntable level, especially the platter? -- Yes, as level as I could get it to be.
[2] Is the arm mounting collar and horizontal bearing housing vertical with respect to the platter? -- Yes.
[3] Is the VTF as recommended by Ortofon, or at least not less than the minimum of the recommended range? (I always start with a setting 0.25g below the maximum recommended figure and work from there.) -- I now have VTF at 1,67 grams.
[4] Do you still have problems if the bias dial is turned to zero? -- the problems are intermittent (which is what makes this so maddening). Last night started acting up again around 4 - 5 minutes into the playback. Then it suddenly decided to play fine and only start acting up toward the end of LP. Then later on, decided to play fine, beginning to end. So I never know what's going to happen next.
[5] Is the azimuth correct? (you can use a mirror to check this.) -- haven't checked azimuth -- Rega RB300 doesn't have removable headshell, so not sure how to adjust that?
Not sure what exactly is meant by 'bias'? Anti-skate?
Don't you just hate it when you cannot detect where the post ends and a signature line begins?
Alex.