Hi Mike: to make Direct Coupling a success the wood-screws must be tightened just so, just like tuning an instrument. So I use several wood-screws and I do indeed use lock-washers (or rubber-sided washers) to go between the head of the screw and the Lenco top-plate. I tighten until the washer is snug and solid with no sign of movement (and solid enough that if I try to move it with a screwdriver it can't be moved), and no further. I also use bolts in the original bolt-holes as Lenco intended. Also, I have Direct Coupled Lencos both with and without nitrile rubber as a shim (there seems to be some variation in the height of the top-plate), and have found absolutely NO sonic or musical penalty, recipients of either of these types of rebuilt Lencos have been universally gobsmacked, and I use both myself and am myself gobsmacked (thank you Dr. Lenco!) at the speed, detail, high, lows, midrange, power, bass and incredible dynamics, in either iteration!!
Hi Chuck: the Decca is a hummy cartridge (like the Grados), no doubt about it. The hum you're experiencing is the Decca picking up the motor's electro-magnetic field. So far, the only way to wipe this type of hum out is to follow Mario's recipe of two sheets of mu-metal glued to the platter. Click on Mario's system to see how it is done. In my own system the Decca also hums (like the Grado), but at such a low level that it is inaudible when playing music and I am not motivated to do the mu-metal mod. Also, I'm used to this sort of thing, being a fan of both Grados and Deccas (both of which hum on most turntables to some extent), and so it simply doesn't bother me (like tube fans used to some level of tube roar). You could try grounding the Lenco motor itself and see what happens, and as usual try grounding the 'table and not the arm, vice versa, both together, motor alone, all together, and so on until you achieve the best level of silence, every system responds differently to these combinations.
Over here I took my Mr. Red (copyright Mike Green ;-)) on the Great Travelling Lenco Road Show to Toronto, where a manufacturer and distributor of high-end audio goodies heard it, and he and his associates were blown away (it turned into a mega session with hours of music, no one could tear themselves away), and now there's a good chance the Lenco will be used to more effectively demonstrate their wares at an upcoming audio show, and in their shop. I won't report further until things are certain, but at least the prospect is pretty exciting news!! In order to make the demonstration more effectively, I used a $200 cheapie high-output MC to show what it can do with one hand tied behind its back, my beloved Satin M-117 with removable stylus, mounted on my Morch UP-4. Vive la Idler-Wheel!!!
