Newbie Question: VTA and Rega P25/RB600


Hi all ... recently I've returned to vinyl (and diggin' it!) with the loan of a good friend's vintage Thorens, and while I'm awaiting delivery of my Rega P25 I am wonderin' about setup of the Rega, specifically, about the lack of VTA on the RB600.

My questions would be (and feel free to throw more in, not sure I really know what to ask at this stage)

1) What are the sonic affects of VTA out of whack/not optimized?
2) How do aftermarket mods work in regards to the RB600?
3) Will I need to worry about VTA if I use a none-felt mat?
(Dyna vector 10x4 cart)
breeno
Origin Live and Expressimo Audio both make variable VTA adjusters for the Rega arms. They are around $40. They are threaded adjusters, and not the easiest to use, but they do work. You can dial it in exactly, with a little patience and a good ear.
Generally, to adjust VTA, you start with the tonearm level while it is playing. Then, you put the arm back on the clip, and perform an adjustment, either up or down. Listen to the result, and determine if you went the right way or not. Make only small adjustments, and play around like this until you get the best sound. Different cartridges like different VTA, and you can only get it right by listening, and adjusting.
As per Mara & Twl. I'll add: patience is rewarding & keep the arm level, if not, SLIGHTLY off (hi or low) until yr cartridge settles. Then go back & re-adjust. Don't worry, it's easy!
I believe the 10x4 dyno is pretty on for the rega, and you may not need to adjust vta for it. You should look into the specs on it as they compare to the rega cartridges. Better yet, contact a rega dealer, or the importer and ask.

enjoy the vinyl!
Also check out Clearaudio Aurum Beta - it is short and very nearly perfect without any VTA adjustment. It is a great Cartridge regardless.