Shure M3D problems - help?

[montesquieu]

Do the different stylus radii you quote (.25, .32, .35 (units?)) correspond to different eras of 78s, or to different manufacturers?

Eras. Essentially the groove got smaller as time passed. Most of the factory '78' cartridges out there are for late stuff (late 40s-50s) so use a 0.25mil (as opposed to the 0.7mil of later mono and more or less all stereo LPs, or 1.0mil of early microgroove mono LPs). Earlier 78s used thicker grooves than this. I have some from the early 20s, and quite a few from the 1930s. Essentially I use the size that's quietest in the groove.

[Barry]

Thanks for that Tom.

Between posting my question and receiving your reply, I had a look on Google and came across this specialist site: http://www.charm.rhul.ac.uk/history/p20_4_6.html.

They talk about stylus radii of between 1.8 and 4 thousand of an inch (mil).

[montesquieu]

Thanks for that Tom.

Between posting my question and receiving your reply, I had a look on Google and came across this specialist site: http://www.charm.rhul.ac.uk/history/p20_4_6.html.

They talk about stylus radii of between 1.8 and 4 thousand of an inch (mil).

Yes it seems Americans talk about thousands of an inch (using the term mil) but of course in metric mil means something else entirely!

The designations are from Expert Stylus where I got the styli. Just looking he they are actually marked 3.x CT (!) don't quite know what that means at all.

[montesquieu]

Can see the 11g weight/thick spacer on the headshell - enables the M3D to straight on in place of an SPU and gives me the 5g tracking weight.

Deleted the previous picture as it had left and right channels reversed - this is the correct wiring for one of these in a standard headshell.