What does irama level refer to?

What will be an ideal response?

• Irama levels refer to the ratios among the different subdivisions of the balungan beat. The result is the balungan melody being played simultaneously at various related tempi. For example, the bonang barung plays at twice the density/rate of the basic balungan melody by subdividing the balungan beat into two quicker units, the bonang panerus could subdivide the balungan beat into four even quicker units, resulting in the ratios 1:2:4, and so on.
—Irama levels are analogous to________ what?
• A process compared by Ward Keeler to a car shifting down to a lower gear to go up a steep hill.