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Channel imbalance & vinyl thickness

daftcombo

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Some records seem to be hotter in one channel than in the other. It can be on the whole record, on only one side, during the whole LP or only the beginning of both sides or only one. It seems to me that it could be a question of thick records (like 180g LPs) and thinner ones and the way the needle runs in the groove according to the thickness.

Do you have any observations to share about that topic?
 

Zoomer

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Yeah vinyl, I remember it well, always something to worry about... :p
 
OP
daftcombo

daftcombo

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At least half of my record collection never had a CD nor digital release. Still want to listen.
 

sergeauckland

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Some records seem to be hotter in one channel than in the other. It can be on the whole record, on only one side, during the whole LP or only the beginning of both sides or only one. It seems to me that it could be a question of thick records (like 180g LPs) and thinner ones and the way the needle runs in the groove according to the thickness.

Do you have any observations to share about that topic?
I can't see how the thickness of the record is relevant, as the depth of the groove is tiny in comparison. However, I've found unbalanced records to be quite common, especially those from the early 1960s when stereo was still a new thing. It may be that it was deliberate, given that there is no requirement for the singer to be central on the image, or it could just be sloppy mastering/cutting. Given how new stereo was then, I can expect that the stereo cut was given special attention, so doubt it was sloppiness. My feeling is that it was indeed deliberate, given that at a live performance, the singer could well be off-centre to the stage, and stereo was felt at the time to be trying to emulate a live performance.

If it's still happening on current pressings of new material, I can't comment, but in this case I think it's more likely to be sloppy processing rather than deliberate.

S.
 

Pluto

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Given that the horizontal modulation of a vinyl record is the sum signal (i.e. L+R) and the vertical modulation is the difference (L-R) this means that if, for any reason whatsoever, the coil assembly within the pickup is not accurately aligned with respect to the same coils within the original cutter head, the result is likely to be any combination of offset (i.e. LR imbalance) and/or reduction of stereo width (i.e. crosstalk).
 

avanti1960

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Chances are the imbalance has nothing to do with LP thickness but it is a common, usually slight problem with vinyl playback that can be corrected.
Double check all aspects of alignment and forces-
Make sure the overhang at the stylus tip is set according to the two null points of your alignment protractor. Check that the cantilever is parallel / centered to the runway lines of the protractor.
Make sure that the platter and top of the cartridge / headshell are perfectly level when the stylus is in the groove.
Double check the vertical tracking force and anti-skate.
Final check is azimuth- vertical alignment of the stylus and internal magnet / coil assembly. Ideally you would use a specific meter to check but you can do it by ear. If the right channel (for example) is still slightly louder after all of your checks, try tilting the cartridge to the right of vertical when viewed from the front- just a tiny amount. You can put a 1/8 in. strip of a business card on the right side of the cartridge between headshell and top of cartridge. If the imbalance i to the left, put the card shim on the left top of the cartridge. Good luck !
 

anmpr1

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I have records with obvious balance mismatches. I never attributed that to the thickness or weight of the plastic. Also, phono carts are known to exhibit variable balance errors; some output errors are temperature dependent. That is why you really need a balance control (and a mono switch) for analog sources.
 

Unclevanya

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If this really concerns you why not have different mats of different thickness and test using the same record.
 
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