Conn. Gen. Stat. § 33-1152: Bylaw increasing quorum or voting requirement for directors.

(a) A bylaw that fixes a greater quorum or voting requirement for the board of directors or that requires a meeting of members to be held at a place may be amended or repealed: (1) If originally adopted by the members, only by the members; (2) if originally adopted by the incorporator or incorporators or by the board of directors, either by the members or by the board of directors.

(b) A bylaw adopted or amended by the members that fixes a greater quorum or voting requirement for the board of directors may provide that it may be amended or repealed only by a specified vote of either the members or the board of directors.

(c) Action by the board of directors under subdivision (2) of subsection (a) of this section to adopt or amend a bylaw that changes the quorum or voting requirement for the board of directors must meet the same quorum requirement and be adopted by the same vote required to take action under the quorum and voting requirement then in effect or proposed to be adopted, whichever is greater.