Bmaj7#5 is B, D#, F## and A#. It keeps the major 3rd and 7th of , but raises the 5th one fret to the sharp 5th (F##).
The sharp 5th is the note to follow. It can rise one more fret to the 6th or fall back to the natural 5th as the harmony changes.
Keep it audible. Without the sharp 5th, the remaining notes only spell .
Also written BM7#5, BΔ7#5, B+M7 or Bmaj7(#5).

How you get to it. The turn that lands on Bmaj7#5 is to — the ii and the V of B — and shares its third and seventh with , so the hand barely moves between them.
Hear it land:→→
Contains Bmaj7#5 and adds ninth, flat fifth and thirteenth.
The common shapes and the derived voicings come from different places, and both are explained in how this site is built.
Shows each chord the way this style would voice it, and marks which of its alternatives belong to the idiom.