Folks, just so you know, 50 microns is about the same as 2 mils (which is how groove deflection is measured in the US if you have American-made LP mastering gear). Many systems use microns these days as many cutter systems are European-made.
2 mils (ever so slightly over 50microns, which is ~1.97 mils) is standard level for 0VU at 1KHz on our lathe and cutter system (Scully lathe with Westerx 3D cutter head, Westerex 1700 mastering electronics with custom tube amplifiers for the cutter head). **3db more is 4 mils.** This is because 3 db more requires double the amplifier power to cut the groove. That would work out to 100 microns.
Its really obvious why no-one other than Nandric has reported any tracking issues in this regard. Its because any arm made can track 2 mils (The older Technics 1200 machine we often use to test our cuts has no troubles doing it; we use this machine with an inexpensive cartridge to make sure that a groove we cut can be played by a common turntable). His magical number of 70 microns is about 1.43 db over 0VU on our system. That's not a hard value for most arms (including the humble Technics) to do as well.
The Triplanar has no worries doing this- we've brought lathe cuts back to the shop and played them on our system no worries. The big danger in cutting louder tracks is usually overcutting the groove, not the tracking of the playback at this level, so long as you don't have the usual dangers such as out-of-phase bass or the like (out-of-phase bass can knock the stylus out of the groove). Since the groove noise tends to show up in the pressing process and even then is not a great concern if the mastering engineer did his job right, there really is very little call for going over 0VU when making the cut.
So even though 70 microns is a very slight increase in volume, its also a really rare thing to encounter (the exception being 12" singles on 45rpm and the like). This is because going over 0VU means that the engineer is likely going to have to take some time to set up the groove cut so no playback problems are encountered. For the most part, mastering houses like to avoid that sort of thing because the typical cost of mastering is about $400/hour. So a mastering operation will take pains to avoid higher levels like that, even though most arms can play it no worries.
So the conclusion is one or more of the following:
1) the Triplanar to which Nandric refers was/is damaged
2) he does not know how to set up an arm
3) the story is made up.
IOW, the math just does not support his apparently ridiculous story.
2 mils (ever so slightly over 50microns, which is ~1.97 mils) is standard level for 0VU at 1KHz on our lathe and cutter system (Scully lathe with Westerx 3D cutter head, Westerex 1700 mastering electronics with custom tube amplifiers for the cutter head). **3db more is 4 mils.** This is because 3 db more requires double the amplifier power to cut the groove. That would work out to 100 microns.
Its really obvious why no-one other than Nandric has reported any tracking issues in this regard. Its because any arm made can track 2 mils (The older Technics 1200 machine we often use to test our cuts has no troubles doing it; we use this machine with an inexpensive cartridge to make sure that a groove we cut can be played by a common turntable). His magical number of 70 microns is about 1.43 db over 0VU on our system. That's not a hard value for most arms (including the humble Technics) to do as well.
The Triplanar has no worries doing this- we've brought lathe cuts back to the shop and played them on our system no worries. The big danger in cutting louder tracks is usually overcutting the groove, not the tracking of the playback at this level, so long as you don't have the usual dangers such as out-of-phase bass or the like (out-of-phase bass can knock the stylus out of the groove). Since the groove noise tends to show up in the pressing process and even then is not a great concern if the mastering engineer did his job right, there really is very little call for going over 0VU when making the cut.
So even though 70 microns is a very slight increase in volume, its also a really rare thing to encounter (the exception being 12" singles on 45rpm and the like). This is because going over 0VU means that the engineer is likely going to have to take some time to set up the groove cut so no playback problems are encountered. For the most part, mastering houses like to avoid that sort of thing because the typical cost of mastering is about $400/hour. So a mastering operation will take pains to avoid higher levels like that, even though most arms can play it no worries.
So the conclusion is one or more of the following:
1) the Triplanar to which Nandric refers was/is damaged
2) he does not know how to set up an arm
3) the story is made up.
IOW, the math just does not support his apparently ridiculous story.