My favorite is the MoFi Geo Disc. Makes alignment so easy. The purpose by the way is to align the cartridge at one point in its arc. A longer arm reduces tracking error across the record but makes no difference in alignment at that one point.
How to choose the right protractor for my effective tonearm length
Hi, I have 2 turntables that I want to align correctly. TT-1 has an effective tonearm length of 223.5mm and 19mm overhang, and TT-2 has an effective tonearm length of 215mm and 15mm overhang. I currently have a Baerwald standard protractor that was made in Great Britain. It says the Vinyl source on it. And have a basic mirrored Stevenson protractor. Please I need help. Thanks!