Parallel? How do you set the VTA?


Silly question, but how do you guys determine whether your tonearm is parallel to the record surface? I had my tonearm set up happily for months, but recently started messing around with the cartridge alignment and the VTA, and I'll be damned, but the folded index card method gets me nowhere now. Even with adjustments I keep getting the same visual effect. Happily my ear tells me when the setting is off, but as a base, how do you determine conclusively your tonearm is parallel? For reference, I have a VPI Classic. Thanks.
actusreus
Zenblaster wrote, "I have to admit that after initial set-up I only change vta when something doesn't sound right."

Oddly enough, that's also why Paul and I adjust for each LP. It's not about measurements or theory. We adjust because if we don't, it doesn't sound right.

I could describe in excruciating detail but that would make it seem much harder than it is. As Raul kindly noted, the actual doing typically takes just a few seconds.

That's us... may not be you. As Jazdoc said, whatever works for your ears and priorities is best, so apologies to Actusreus if I pooh-poohed his preference for an objective baseline position. Each to his own.
"...if Dover can hear a change of 0.00635 degrees in the SRA, a change of a fraction of degree in the ambient temperature would result in a change in the sound that he could hear.
Very true. During Raul's visit (several years ago) we played music for several hours, then broke for dinner. The setup was well dialed in when we stopped, but on re-starting 45 minutes later the music sounded flat, dull, lifeless.

All electronics had been left powered up, but I realized that the cartridge must have cooled down from non-use (it was December and COLD outside). I tweaked VTF up a tiny bit.

BANG! Dynamics, pace and jump returned in spades, instantly. Raul asked what I'd done, the adjustment was so quick and tiny he couldn't see from the sofa. I demonstrated. All I'd done was nudge one of the O-rings on my arm stub inward by less than its own thickness, a VTF increase of much less than .01g. I went back and forth a couple times and the sound alternated accordingly.

Some setups are indeed that touchy.
04-11-13: Larryi
The only way I could see myself doing album-by-album VTA adjustment would require ownership of a rare Air Tangent arm that allowed for motorized VTA adjustment by remote control. That way, one could actually hear the change occurring on the fly.
Another way would be if you have a good pair of headphones that could be listened to while standing next to the turntable. That is what I have done.

Even so, my own feeling, like yours, is that life is too short to be doing this all the time, and it is rare that I find myself fiddling with the setting these days. I suspect, though, that the stylus profile of my cartridge (Grace F9E Ruby with Soundsmith's $250 retip) results in the VTA/SRA setting being somewhat less critical than it is with the cartridges that are used by many of the others who have posted.

Regards,
-- Al