The possible combinations and resulting shapes are:
  Here is the information transformed into a wiki table format: {| class="wikitable"|-! Binary  !! Hex      !! Shape!! Comment  |-| 00XX    || 00h-03h  || <code>\_________  (</code> || same as 09h)  |-| 01XX    || 04h-07h  || <code>/_________  (</code> || same as 0Fh)  |-| 1000    || 08h      || <code>\\\\\\\\\\</code> ||   |-| 1001    || 09h      || <code>\_________  (</code> || volume remains quiet)  |-| 1010    || 0Ah      || <code>\/\/\/\/\/</code> || |-  | 1011    || 0Bh      || <code>\"""""""""  (</code> || volume remains high)  |-| 1100    || 0Ch      || <code>//////////</code> || |-  | 1101    || 0Dh      || <code>/"""""""""  (</code> || volume remains high)  |-| 1110    || 0Eh      || <code>/\/\/\/\/\</code> ||   |-| 1111    || 0Fh      || <code>/_________  (</code> || volume remains quiet)|}
We can observe that there are only 8 resulting shapes even though they are selected by using a 4-bit value.