Ortofon OM20 lousy tracking

[Svend N]

You go into your printer settings and change it by small amounts until it’s right

^^^What he said... In the print dialogue in Acrobat Reader, find the section called Print Scaling and Handling > Custom Scale, and adjust from there until it's right.

[Mike Reed]

Obvious is always good, we've all probably missed the obvious, but wouldn't lowering the VTF make the cartridge run higher?

Indeed. At the lower VTF the cart. body will be higher, hence allowing more clearance, if the body is hitting the record anywhere. Of course, raising the VTA should have a similar or even greater effect, as it's often the back of the cart. which will snag the record. Upping the VTA should also change the presentation toward more upper frequencies, but correspondingly can appear more dynamic as a result. The reverse is true that with the arm down at the pivot, the sound becomes more bassy but also more diffuse.

[Stryder5]

I get where you're coming from now, I had misinterpreted your post, sorry.

Indeed. At the lower VTF the cart. body will be higher, hence allowing more clearance, if the body is hitting the record anywhere. Of course, raising the VTA should have a similar or even greater effect, as it's often the back of the cart. which will snag the record. Upping the VTA should also change the presentation toward more upper frequencies, but correspondingly can appear more dynamic as a result. The reverse is true that with the arm down at the pivot, the sound becomes more bassy but also more diffuse.

[guy]

"My dealer installed Ortofon OM20 on my Rega RB300 tonearm"

When you say "dealer", what is his trade ?

[magiccarpetride]

"My dealer installed Ortofon OM20 on my Rega RB300 tonearm"

When you say "dealer", what is his trade ?

He's a purveyor of all things analog. Great, fantastic guy, I have really great experiences with him, but he is super busy so in the meantime (while I'm waiting for his availability) I'm trying to troubleshoot this problem with your guys's help.

[Barry]

Just something which occurred to me whilst reading the o.p.'s mention of the snag now happening on the inner grooves since lowering the VTF. Why? I suggest because the cart. body is now clearing the record, but not enough for the inner grooves.

A throwaway thought, but visually check the clearance of the body at different points on the record. Bit bloody obvious, so apologies for grandma sucking eggs, as they say.

If the clearence between the cartridge body and the record is not constant across the record surface, then the arm pillar cannot be truly vertical with respect to the turmtable arm mounting.

The OP complains of mistracking due to the cartridge jumping or groove skipping. This suggests to me a problem with excessive bais, and not of any deviation from 'correct' arm/cartridge geometry.

[Mike Reed]

If the clearence between the cartridge body and the record is not constant across the record surface, then the arm pillar cannot be truly vertical with respect to the turmtable arm mounting.

The OP complains of mistracking due to the cartridge jumping or groove skipping. This suggests to me a problem with excessive bais, and not of any deviation from 'correct' arm/cartridge geometry.

I agree, Barry, and it may well be wrong biasing due to the shift in snagging position, but as you say, it may be the alignment. Insufficient clearance is likely to affect the outer grooves more, come to think about it, as few records are totally flat. Mind you, I've had dished records which rise in the centre. Still worth checking that there's adequate clearance, though.

[Barry]

Ah - I hadn't considered 'dished' LPs. I assumed the OP was having problems with all of the records he played.

[magiccarpetride]

Ah - I hadn't considered 'dished' LPs. I assumed the OP was having problems all of the records he played.

Yes, all records I played so far have the same problem.

[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).