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Right channel bias in analog setup

As an analog newbie, I’ve been fighting with my turntable setup for a while now and am raising my hand for some help please. I have an original VPI Scout with a new Denon 103R cartridge connected to a Denon AU-300LC step-up transformer. This is connected to a Sutherland 20/20 phono pre-amp, which is connected to a Mark Levinson 326S pre-amp/Levinson 436 monoblock/Wilson Audio Sasha output. For some reason, when I am playing records, there is an obvious right channel bias where imaging seems right of center, regardless of what record I’m playing. When I switch to digital sources such as my CD player (Levinson 390S) or streaming (Amazon Echo Link), with the same music, everything is centered as it should be. I assumed the problem was an azimuth setup problem as I've read that channel bias can be due to balance problems there. After trying different variations, I finally got the system to image correctly, but the arm/cartridge is ridiculously leaning to the left. I can't believe this is the correct setup and that it won't eventually hurt the records and/or the cartridge over time. Any suggestions/help would be greatly appreciated. Thanks.
henrus
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cleeds
5,764 posts
 
henrus

... I finally got the system to image correctly, but the arm/cartridge is ridiculously leaning to the left. I can’t believe this is the correct setup ...
Obviously something is amiss.

While azimuth does have an affect on channel balance, so does horizontal tracking angle, and that’s something many users fail to properly align. Please tell us what tools you’re using, and how you’re using them, to align this cartridge.

I’d also experiment with reversing the left and right inputs to your phono stage and see if the problem jumps channels. If it doesn’t, you know the problem is in your phono stage. Improper anitskate can also affect channel balance.

lewm
12,627 posts
 
Someone misled you.  Changing azimuth to fix a problem with channel balance can work to some degree, if the imbalance is minor, but in the process of correcting that problem, you inevitably end up with an extreme setting of azimuth that is not acceptable in terms of cartridge wear and LP longevity.  (Both the stylus and the grooves can be damaged by an extreme angle of azimuth, where you are now.)  Azimuth affects most directly the level of crosstalk, the amount of L channel signal that gets into the R channel and vice-versa.  For now, I advise you to re-set your azimuth to 90 degrees as best you can by eye, so that the stylus sits symmetrically in the groove.  Then we can talk about your channel balance problem.  From what you have already written, I wonder whether you have either too much or too little anti-skate set on your tonearm.  Have you played with that setting?
henrus OP
12 posts
 
Thank you both for your quick responses. Gosh this forum is amazing. I will set the azimuth back to 90 degrees as certainly there was no way that was the correct setting. As far as anti-skate, unfortunately the VPI Scout does not really have a great solution for that. Their way of providing anti-skate adjustments involve adjusting the coil wire connecting the tonearm, which doesn't really provide for fine adjustments. Regardless, I've tried coiling the wire more and less tightly and it didn't seem to have any effect on the right channel bias. I don't have the mechanical anti-skate mechanism as that was added in the Scout v1.1., though I may be able to purchase it from VPI and add it to mine. 

As for horizontal tracking angle, I'm not sure exactly what that means. I seem to have misplaced my alignment jig that came with the turntable so I just printed an alignment diagram and used that to align the cartridge if that's what you mean. If there is a good cartridge alignment instruction page you can recommend, I'd appreciate it. The VPI manual is lacking and difficult to follow. Thanks.
millercarbon's avatar
millercarbon
12,531 posts
 
I seriously doubt its alignment. Odds are your "obvious right side bias" means the center image is a few inches, to maybe a foot, to the right. If that is the case then my question is does it shift as you play a record? Because the way the twisted wire thing works it causes anti-skate to change as the arm moves across the record. Honestly don't even know which way, that's just how messed up a thing VPI has made here. No idea how much torque the wire puts on the arm, or if it increases or decreases as the arm sweeps across a record. Oh, I can see what it would seem to do. But so many people have had so many different problems with it I seriously doubt anyone really knows. Anyway, one thing I am pretty sure of, it is not consistent across the record. So you should be able to hear the image shift and be different at the end compared to the beginning of a side.  
henrus OP
12 posts
 
Oh my god. @millercarbon, you are completely right. I have noticed that when the last track of the record is playing, the right channel shift is noticeably less pronounced. Though has anyone else mentioned this problem? It's so clearly obvious that anyone with a Scout or similarly built turntable should be reporting it? How the heck can you correct for something like this. Crazy,
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