I agree with Tom, if two levels agree, you gain nothing. If they don't agree you loose
Get a standard long level of the I beam type, and figure a way to fit your current audible level into it. You can check the accuracy of any level by putting it on any flat surface and getting it level with shims of paper. Then turn it end for end and see that it's still level. If you have your audible level in an I beam type unit, you can calibrate it by shimming the fit between levels. Tom Fowle
