Adjusting the Spring Suspension AR - Merrill and other turntables
By George Merrill for my AR - Heirloom ownersThe adjustment is done via the three nuts that retain the springs for the suspension system. By turning these three nuts clockwise viewed from the bottom of the turntable, the nuts will rise towards the top of the table lifting the grommet, spring, sub-chassis and platter system. Turning the three wing nuts counterclockwise will lower the whole system. These wing nuts have nothing to do with the actual tuning of the sub-chassis, the only function that they perform is to raise, lower and level the subchassis platter system within the base itself. By adjusting the nuts, you can raise the subchassis all the way to the point where it hits the underside of the top of the turntable base (if this happens feedback will occur). Or you can lower the sub-chassis to the point where the underside of the platter strikes the motor pulley. If these wing nuts are adjusted unequally, then the subchassis will tilt causing it to be unlevel with reference to the top of the base. One of the main points in having a proper turntable set up is the float of the subchassis; be sure that it floats (Sub-chassis not bumping the bottom of the base or the platter scraping the motor pulley) and be sure that it is level with the base top. NOTE: the sub-chassis arm-mounting platform does not have to be even in height with the top of the base, just level to the top.
Adjustment Adjust the nuts to the point where the subchassis floats and does not touch the underside of the base top or the underside of the platter does not touch the motor pulley. As you do this adjustment, you can take a measurement from the top of the platter to the top of the base to make sure that the distance is equal all the way around the platter. This will ensure you of having the subchassis level with the top of the base. Wound springs have a soft side at the start of the wind. By rotating the springs better centering of the spring stud in the sub-chassis holes can be achieved. Spin Some Vinyl!