Martinhall wrote, "A `feature' yet unmentioned(unless I missed it?) A DD TT unit that provides good enough torque to sustain resistance to stylus drag, unfortunately exhibits magnetic noise induced into the cartridge as it tracks the inner part of a record."
If Martin is still alive and still cares, let me say that the fact that he observed this phenomenon with one DD turntable (Micro Seiki) and presumably one unnamed cartridge does not mean that this is a general issue with all DD turntables. And if it were an issue with a particular combo of tt and cartridge, it is a relatively simple matter to devise a shield that prevents motor EMI from affecting the cartridge. Also, the M-S DD turntables (DDX and DQX) are not highly regarded in relation to the large number of high quality belt drive tt's made by M-S or indeed in relation to other vintage Japanese DD turntables, so it is a bit unfair and misleading to form an opinion of all DD turntables based on the M-S ones.
If Martin is still alive and still cares, let me say that the fact that he observed this phenomenon with one DD turntable (Micro Seiki) and presumably one unnamed cartridge does not mean that this is a general issue with all DD turntables. And if it were an issue with a particular combo of tt and cartridge, it is a relatively simple matter to devise a shield that prevents motor EMI from affecting the cartridge. Also, the M-S DD turntables (DDX and DQX) are not highly regarded in relation to the large number of high quality belt drive tt's made by M-S or indeed in relation to other vintage Japanese DD turntables, so it is a bit unfair and misleading to form an opinion of all DD turntables based on the M-S ones.