Question: How do I align the cartridge on the AT-LP120-USB and AT-LP1240-USB turntables?
Answer: Proper alignment of a turntable’s stylus (needle) is needed in order to realize the full potential of the turntable cartridge and stylus system. Proper alignment of the stylus as it relates to the record groove insures the most accurate reproduction of the recording and the least amount of wear on the record and the stylus. Various tools are available for achieving this alignment.
At the very least, the specified stylus overhang (the distance the stylus tip extends beyond the center spindle when the headshell is positioned directly above the spindle) should be set. A simple way to set overhang is to use an overhang gauge that has markings in millimeters (mm). Common stylus overhang distances are 15 mm (as is the case for our AT-LP1240-USB turntable) and 16 mm (for our AT-LP120-USB turntable), but other lengths exist as well. Note that on a turntable that includes a premounted cartridge/stylus the overhang has typically been preset at the factory.
To insure the most accurate reproduction of the recording, low noise and least amount of wear on the record and stylus, it is important that the stylus be aligned in such a way that its tip remains as tangent to the record groove as possible as it travels across the record. With a pivoted tonearm, it is possible to achieve perfect tangency at only two points as the tonearm travels in an arc across the record. These two points are known as null points (points where there is no tracking error). A two-point cartridge alignment protractor can help achieve this tangency. You can download and print a two-point protractor from our website – just be sure to print the protractor to actual size.
The two-point protractor has a dot for the stylus tip to rest on and a grid to which the stylus cantilever (the tube that extends from the cartridge body and has the stylus attached to it) aligns. If the stylus cantilever is not easily seen, align the sides of the cartridge body to the lines on the grid instead. In this case, we are assuming that the cantilever is centered and straight as it relates to the sides of the cartridge. Like all two-point protractors, ours has an outer dot/grid and an inner dot/grid. If you choose to use a different protractor, it is important to select one that is suitable for the effective length of the tonearm on your turntable. For the AT-LP120-USB turntable, the effective length is 230.5 mm. For the AT-LP1240-USB turntable, the effective length is 230 mm. The protractor on our website is suitable for both of these turntables.
With the mounting hardware loose enough to allow forward and backward movement of the cartridge in the headshell, position the cartridge to allow the stylus tip to rest on the protractor’s outer dot (the dot farthest from the center spindle). This will set the correct stylus overhang. Next, align the stylus cantilever to the lines on the grid. If the cantilever is not easily seen, align the sides of the cartridge body to the lines on the grid instead. Provided the stylus tip has been attached properly during manufacturing, the tip will be tangent to the record groove when the cantilever is aligned to the grid. Note that you may need to twist the cartridge slightly in the headshell (when looking down on it from above) to achieve the best alignment to the grid. When done, the cartridge may not necessarily end up being parallel to the headshell.
Once you’ve aligned the cartridge to the outer dot/grid, move the tonearm to the inner dot/grid to double-check that the cartridge and stylus align there as well. They should align to the inner dot/grid without further adjustment. If they don’t, recheck that the stylus overhang has been set correctly, that the headshell is properly attached to the tonearm, and that the stylus is properly attached to the cartridge. Make any necessary adjustments, then recheck the alignment against both the outer and inner dots/grids. Once aligned, tighten the mounting hardware until snug.
If you need additional assistance with aligning your cartridge, please contact our Audio Solutions Department.