Why are the vocals on some records hidden behind the music on my system?

@uberwaltz 
Yes; I adjust for every side of every record.  My system easily resolves the difference and it only takes a moment.  The effect is substantial and very much worth the effort to me.  I recognize that not everyone is that picky or sensitive and that's just fine.  To each their own.   

I'd had a Rega with a LOMC for years and it just sounded like I was missing something.  I then went to a Magnepan Unitrac arm with the same cart and a whole new world opened up for me. That was in 1984 and I've never looked back. 

The OP just described the same effect after doing some more adjustment, so thought I'd share my experience on the point.  That's the joy of this hobby: Getting to happy listening. 

@scooby2do - your Soundsmith Aida Has an Optimized Contour Line Contact Stylus - these require the MOST PRECISE setup!

I would highly recommend setting it up using the Best Mint Protractor first (or a protractor that provides for the same amount of precision) and get a younger pair of eyes to perform the setup for you with a very good loupe.

My setup took around two hours of dickering around with the setup and verifying it was correct using a digital camera for closeup analysis.

This stylus type is critical of mis-alignment but the rewards of getting it right is well worth it.

A printed protractor WILL NOT give you the precision required!

The anti-skate method as detailed on the Soundsmith web site basically mirrors Almarg’s post (i.e. you want to make sure there is no sideways force on the stylus) - with a few little refinements that may make a difference...
https://www.sound-smith.com/faq/how-do-i-adjust-anti-skating-my-cartridge

To see if the position of the stylus is being altered when you lower the stylus on the record you should be using a good loupe. The naked eye is not really good enough for Soundsmith cartridges..

It then took just under 2 hours to get the A/S of my Soundsmith’d Denon cart with the Optimized Contour Line Contact Stylus just right. My cartridge is mounted on an Audiomods arm that use a weight and quadrant antiskate system to optimize the A/S force across the record.
http://www.audiomods.co.uk/antiskatenotes2.pdfs

"Dial-in" anti skate systems can present issues that are difficult to rectify - My old rega arm was so far off I had to set the A/S dial to the maximum, so basically I had to use the "trust my ears" method...

• Start with the dial set at zero
• then play a troublesome track while you advance the dial in equal increments (e.g. 1/4 of a turn)
• when is sounds good set the dial back half an increment to see if it sounds better or worse.
• adjust in fine increments until best image is attained
• It might be an easier/faster way to proceed.
• Do this at the center of the recording surface, that way the beginning and end of the recorded surface will only be a little off, which is always the issue with dial A/S systems.
• At some point during this process this cartridge should snap into focus.
  

Hope you get your problems solved soon - Steve

Well everybody guess what? After adjusting and re-adjusting just about everything that has been brought up until my head was spinning I found something that we all missed. At least not that I remember seeing and was one of the easiest to fix and that was the VTF. The Aida shows a range of 1.3 to 1.6 grams as the optimum settings. I was running it at 1.3, just for grins I decided to increase it to the max of 1.6 and played an album that sounded bad and the vocals had increased to the point that I could understand what he was singing over the music. So just for grins again I increased it a little bit more and got even more vocals I have stopped at 1.8 grams which is 1/2 gram more than where I started. Maybe it just takes more weight to get the stylus into the groove far enough to retrieve the sound? Sure making all the other adjustments didn't hurt either but that is what has made the most improvement so far. williwonka- your right my old eyes aren't what the use to be, so I have been using a 30x jewelers loupe to view vta and attempt to set anti-skate. Even with that it is hard to see any deflection of the cantilever but it is enough to see the angle of the stylus and get it at close to 90 degrees.

When the VTA is off by 1/10 degree the distortion is up 100%. 

Sounds like a nice find OP, sometimes it is so easy to chase around in ever decreasing circles only to realise you then have missed the  blindingly obvious...lol.
It is something I never even thought of asking but now you state it, I have just about always run my vtf at the top end of the spec for the cartridge used as it does seem to "dig deeper" into the music.
Of course all the time spent on carefull setup has not gone to waste for sure!
Now sit back, relax and enjoy the music!