Some of the older VPI classics come without VTA and some of the newer ones have VTA on the fly.
I have a Classic 1 that does not have VTA on the fly, but the VTA is still adjustable. Basically you have to snug up 2 set screws on the regular adjustment or the sound loses focus.
How much of a difference does it make? My understanding is it is required for LPs of different thicknesses. But is it really required? Do you ever end up changing the VTA of your TT?
VTA does make a difference. On the fly is not required, the regular VTA adjustment is just fine. I set the VTA with one of my medium thickness (the majority of my collection falls into this category) record and it does just fine with the thicker and thinner albums. Occasionally I get the urge to fiddle with VTA, probably as the stylus wears...
Here is the regular VTA adjustment http://www.vpiforum.com/viewtopic.php?f=12&t=7175
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