just how accurate do you have to be??

[karma67]

ok so here's where im at with turntable set up...
i use the alignment paper disc that came with the hifi news test record.for my linn arm its an 18mm overhang,to achieve this
i place a m12 nut on a drawn line 18mm from the center spindle then gently lower the tonearm down onto the spindle and eye the stylus tip up against the side of the nut.
once ive done that i then align the cartridge in the normal way using the 2 null points.i know there are more costly alignment gauges about and when funds allow i might go for the one made by mint.

my question is,is this good enough? how would you set the overhang as it seems to me you can be + or - the 18 mm and still get the cantilever square.
perhaps im worrying to much?

[John Gordon]

Jamie,
the important thing about two point protractors is that they are universal - it doesn't matter what arm you use providing you can adjust the overhang and offset. You don't have to know the actual value in mm of overhang, as it will be correct if the alignment is done accurately, so forget about setting 18mm exactly.

For an arm with a slotted headshell like yours you adjust both the overhang and offset there. Other arms adjust overhang at the arm base.

When the stylus is on the nulls, the cartridge ( or ideally the cantilever) should be parallel to the lines on the grid of the protractor, and not be at an angle, however small.

You will probably have to be patient, use a magnifier, and repeat the process a number of times to get close.

John

[karma67]

Thanks for the advice.yes I know that once you get the null points lined up your overhang is right.i get it in the ball park by using the nut for reference as it only then leaves giving the cartridge a twist, it saves moving the cartridge backwards and forwards etc.