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Cartridge providing off center image - ideas?

uncl_nigel

uncl_nigel

pfm Member
When playing LPs I am getting an image which is to the right of centre whether mono or stereo - at about 1 o'clock instead of 12 o'clock (dead centre).
By reversing channels at various places along the line I have isolated the culprit as being the turntable.

The turntable is an SME 20 and SME V arm with a Grado Sonata. The tracking weight and anti-skating are both set to 1.7gr.

The cantilever looks straight.

Any ideas?
 
Swap the arm cables at the phono stage input and see if the image goes left of centre. If it does, that would point to either the cartridge, arm or arm cable.

Has it just started doing this? If so, what has changed (including furniture).
 
If you've ruled out everything but the cart then it's usually bias that's out or TT a fair whack off level... but if its just suddenly gone like that it could be a fault with the cart. MM's tend to need a bit more bias than MC's (an MC could feasibly be best at as little as 1g bias with 1.7g downforce) and I doubt optimum would be less than 1.3g or so. It effects overall sound as well as image centrality though and bias usually has to be a fair way out to move the image off centre. I presume you have ruled out phono stage?
 
I had a similar thing with a new turntable. In my case easing off the bias centered the image.
 
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Mick Seymour said:
Swap the arm cables at the phono stage input and see if the image goes left of centre. If it does, that would point to either the cartridge, arm or arm cable.

Has it just started doing this? If so, what has changed (including furniture).
Click to expand...

Been there, done that - that is how I know it is an issue at the turntable end of things.
 
If you've ruled out the wiring and the electronics, another possible cause of channel imbalance is if the stylus tip isn't perfectly vertically aligned perpendicular to the record when viewed from front on. IOW, the cantilever may look straight but have rotational misalignment ('twist') resulting in the stylus tip being angled and causing one channel to be perceived as having a slightly higher level (but is actually brighter relative to the other more rolled off channel).

Another possibility is that the cantilever suspension has gone off or been damaged, putting the induced magnets out of alignment with the fixed coils. IM cartridges can be more susceptible to the latter, as the moving metal must remain in balanced alignment with both the fixed magnets and the coils.
 
The anti-skating is not the cause - I have just tried values ranging from 0.5gr to 3gr with no movement of the image (I used the Beatles (white) in mono).
 
Craig B said:
If you've ruled out the wiring and the electronics, another possible cause of channel imbalance is if the stylus tip isn't perfectly vertically aligned perpendicular to the record when viewed from front on.
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You have a good point but stylus being perpendicular to the record is just a starting point , unfortunately in most cases it means cantilever alignment within coils would be out (balance shifted) .Hard part is to measure it , if you have oscilloscope and test record you're good to go otherwise try to rotate hadshell anticlockwise (looking from the front of the cartridge ), you will be changing couple things channel balance and cross talk . Another option (expensive) Fozgometer , dr Feickert- Adjust+ or multimeter method .
 
slawekt said:
You have a good point but stylus being perpendicular to the record is just a starting point , unfortunately in most cases it means cantilever alignment within coils would be out (balance shifted) .Hard part is to measure it , if you have oscilloscope and test record you're good to go otherwise try to rotate hadshell anticlockwise (looking from the front of the cartridge ), you will be changing couple things channel balance and cross talk . Another option (expensive) Fozgometer , dr Feickert- Adjust+ or multimeter method .
Click to expand...

Both platter and head shell are level so I am a little wary of twisting the head shell (i.e. the entire arm wand).
Given that the whole SME V seems to be locked down tight and nobody ham-fisted ever goes near it, might it just be a cart that has reached its end?
 
uncl_nigel said:
Both platter and head shell are level so I am a little wary of twisting the head shell (i.e. the entire arm wand).
Given that the whole SME V seems to be locked down tight and nobody ham-fisted ever goes near it, might it just be a cart that has reached its end?
Click to expand...
I didn't realise you're using V tonearm , well you're stuck then unless fiddling with spacers
 
Not too difficult (albeit a hassle) to eliminate either the arm or the cart., and you may have already done this by transposing arm leads and/or cart. tags. You don't say how old (in playing hours esp.) your Nagaoka is, or whether you've inspected the stylus close up (with a loupe?). a gunked-up stylus may not have a bearing on your imbalance but needs attending to anyway. Worth checking your VTF by going back to zero plus zero bias on your Five, floating the arm and re-setting if you haven't already. Knowing the Five, assuming all alignment (VTA etc.) is well, it does tend to point to the cart. (in theory !:))
 
I had a 17D2 do this after too long at the wrong bias setting (rega arm, part of my learning curve) but the cantilever was visibly offset and a little twisted. Thinking further back my first cartridge also had one channel stronger than the other but that was an Elite (Townshend) and QC on a rebadged cheap MM wasn’t something they were too worried about.
New cartridge time I fear.
 
It seems you have ruled out everything other than a failure of the cartridge its self. I had an Ortofon MC that I was using in than SME V that worked perfectly for a couple of years then declined rapidly in one channel and then failed completely. I got a trade in against my present Cadenza Blue that worked perfectly and still does after about 3 years use. Do you have or can you borrow another cartridge to try?
 
uncl_nigel said:
Given that the whole SME V seems to be locked down tight and nobody ham-fisted ever goes near it, might it just be a cart that has reached its end?
Click to expand...

How old is the cart? If it did work fine, and now does not I’d assume it had generated a fault condition. Do you have a nice loupe to inspect the stylus (thread here)? Everyone should have a good loupe, it is amazing what crap can attach itself to a stylus!
 
Checked balance and drift with tracking force and bias at zero - the arm floats with no drift either side so that is not the problem.
 
Tony L said:
How old is the cart? If it did work fine, and now does not I’d assume it had generated a fault condition. Do you have a nice loupe to inspect the stylus (thread here)? Everyone should have a good loupe, it is amazing what crap can attach itself to a stylus!
Click to expand...

No use to me unfortunately - I need 6x to 10x magnification just to read :)
 
uncl_nigel said:
No use to me unfortunately - I need 6x to 10x magnification just to read :)
Click to expand...

Strange, as my myopia (from birth) only crossed the NHS voucher threshold (minus 10) a few years ago. Improved with age, but losing out financially !:)

I have no trouble with loupes (without glasses, of course). Is the Nag. (not being a strict mm, I believe) fixed stylus or removable? If the latter, you're laughing.
 
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