Sub-base

from The Collaborative International Dictionary of English v.0.48

Sub-bass \Sub"-bass`\, n. (Mus.)
   The deepest pedal stop, or the lowest tones of an organ; the
   fundamental or ground bass. [Written also {sub-base}.]
   --Ayliffe.
   [1913 Webster]

from The Collaborative International Dictionary of English v.0.48

Sub-base \Sub"-base`\, n. (Arch.)
   The lowest member of a base when divided horizontally, or of
   a baseboard, pedestal, or the like.
   [1913 Webster]

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