A# Viennese trichord/F
The A# Viennese trichord chord consists of the A# (Perfect unison), B (Minor second) and E (Diminished fifth) notes, with F as the bass note.

How to play the A# Viennese trichord/F chord
- Play F as the lowest bass note in the left hand
- Find A# (Root) on the piano keyboard
- Add B (Minor second) — 1 semitone above A#
- Add E (Diminished fifth) — 6 semitones above A#
- Press all 4 notes simultaneously to sound the A# Viennese trichord/F chord