A spool (128, 500, 600, 700) configured to be movable in a longitudinal bore of a valve, the spool (128, 500, 600, 700) comprising: a shaft varying in diameter along a length of the shaft; and a plurality of annular lands (152, 154, 156, 158) formed on the shaft and spaced-apart by respective reduced diameter annular neck portions (202, 204), wherein the plurality of annular lands (152, 154, 156, 158) comprise at least one annular metering land (152, 154, 156, or 158), and wherein one or more of the the at least one annular metering land (152, 154, 156, or 158) comprises: a plurality of sine notches (206, 210 or 216, 217) formed as a portion of a sine wave, and a plurality of additional notches (212, 214 or 218, 219) having a different shape from the a plurality of sine notches (206, 210 or 216, 217), wherein the plurality of sine notches (206, 210 or 216, 217) and the plurality of additional notches (212, 214 or 218, 219) are disposed in a circular array about a circumference of the at least one annular metering land (152, 154, 156, or 158), and wherein the plurality of sine notches (206, 210 or 216, 217) are interleaved with the plurality of additional notches (212, 214 or 218, 219), about the circumference of the respective annular metering land, such that each sine notch is circumferentially-interposed between two additional notches (212, 214 or 218, 219). a shaft varying in diameter along a length of the shaft; and a plurality of annular lands (152, 154, 156, 158) formed on the shaft and spaced-apart by respective reduced diameter annular neck portions (202, 204), wherein the plurality of annular lands (152, 154, 156, 158) comprise at least one annular metering land (152, 154, 156, or 158), and wherein one or more of the the at least one annular metering land (152, 154, 156, or 158) comprises: a plurality of sine notches (206, 210 or 216, 217) formed as a portion of a sine wave, and a plurality of additional notches (212, 214 or 218, 219) having a different shape from the a plurality of sine notches (206, 210 or 216, 217), wherein the plurality of sine notches (206, 210 or 216, 217) and the plurality of additional notches (212, 214 or 218, 219) are disposed in a circular array about a circumference of the at least one annular metering land (152, 154, 156, or 158), and wherein the plurality of sine notches (206, 210 or 216, 217) are interleaved with the plurality of additional notches (212, 214 or 218, 219), about the circumference of the respective annular metering land, such that each sine notch is circumferentially-interposed between two additional notches (212, 214 or 218, 219). a plurality of sine notches (206, 210 or 216, 217) formed as a portion of a sine wave, and a plurality of additional notches (212, 214 or 218, 219) having a different shape from the a plurality of sine notches (206, 210 or 216, 217), wherein the plurality of sine notches (206, 210 or 216, 217) and the plurality of additional notches (212, 214 or 218, 219) are disposed in a circular array about a circumference of the at least one annular metering land (152, 154, 156, or 158), and wherein the plurality of sine notches (206, 210 or 216, 217) are interleaved with the plurality of additional notches (212, 214 or 218, 219), about the circumference of the respective annular metering land, such that each sine notch is circumferentially-interposed between two additional notches (212, 214 or 218, 219).