Question concerning the Mint Tractor

Tim's geometry clarification was excellent.

In addition, changing VTA on most arms alters VTF, so the cantilever wouldn't be sitting at the same angle as it does during play.

True observation, Tvad. Overhang will surely change every time one plays an LP differing in height from the Mint (or whatever protractor was used).

Adjusting VTA/SRA is indeed an inexact science, but fortunately it's a very exact art. :-) We adjust by ear, for every record. Accurate sound is the goal. Accurate geometry is just a means to that end.

FWIW, most of our VTA adjustments are far less than the thickness of any mat, less than a sheet of paper even. I've posted it a zillion times and everyone thinks we're crazed - until they visit and hear the difference for themselves. Ask Dan_Ed or Swampwalker or Raul. They've all watched me raise or lower the arm by a hair's thickness and heard the sound snap into focus.

Whether its worth the effort is up to each of us of course, but for me it's become second nature and takes literally no playing time. We record the height for each LP so replay setups are instant.

Thom and others have suggested that Paul and I may become less particular about this after Mint-ing. That hasn't happened and isn't likely too. Why should improved stylus alignment in one plane encourage sloppiness in another? My lazy backside understands the appeal, but my ears don't.

Hi Doug,

Thom and others have suggested that Paul and I may become less particular about this after Mint-ing. That hasn't happened and isn't likely too. Why should improved stylus alignment in one plane encourage sloppiness in another? My lazy backside understands the appeal, but my ears don't.

Errors tend to have a compounding effect.

Visualize how the front and rear of a line contact stylus contacts the groove when its offset angle is grossly skewed. Now raise and lower the VTA. You can almost "see" the rooster tail of vinyl being churned in the stylus' wake.

In contrast, compare how a perfectly tangent stylus being raised/lowered in the VTA plane "sees" the groove as the VTA is being changed.

Dunno, this makes intuitive sense to my powers of visualization. My first experience of an ET-2 (linear tracker) brought me to this line of thinking - after hearing how much less critical VTA settings were with this arm.

Ultimately as you say, it's VTA settings are an "exact art".

As I write the above, I'm thinking of along a tangential (sorry, I couldn't resist) line of thought about why perfect alignment matters.

Since we all have our trigonometry hats on, think about the force vectors on a misaligned stylus - how an intended 90 angle force to the cantilever is not a perfect 90 degrees - and how this can result in left/right distortion and a whole lot more (acceleration changes, and with it, changes to dynamic shadings).

Yet another way of saying to get your alignment right.

Cheers,
Thom @ Galibier

Thom,

Good point about errors compounding, and interesting virtual observations from the stylus' POV. I've learned alot by doing those gedankenexperimenten.

The force vectors on a misaligned stylus must indeed put stresses on cantilever and suspension that no cartridge designer could plan for. Of course on a pivoting arm our zenith angle is *always* misaligned, except at two points. Therefore...

I've wistfully noted that the Mint helps me imagine what a good tangential tracker might sound like at all points across the LP. My dream has always been a Kuzma Air Line. Some day...

Point-of-weirdness:
Mint-ing has greatly reduced distortion, but the increased clarity has also made the L to R shift in soundstage as the arm tracks between null points more audible than ever. "Watching" the musicians sidle slowly across the room and back is strange, who knew a string quartet could perform as a marching band?!

As you suggested, we did pay little attention to VTA during the first LP sides after Mint-ing. (Though we'd chosen familiar records, so the VTA # was known and dialed in out of habit.) The music is more holistic, as Swampwalker said, so it's easier to lose yourself in it and we do, very happily. But we're also both driven by an internal sense of what acoustic instruments sound like. Adjustments we know are needed will always be made. Pretty insufferable, I guess. :-)