• Beach 27 (432 Hz)
• Bell Tow­er 27 (432 Hz)
• Marim­ba 27 (432 Hz)
• Baltic Sea on 27 Stones (432 Hz)
• Mana 27 (432 Hz)
• Baltic Light 1 (128 Hz
• Home 1 (128 Hz)

27 = 27 Hertz — the ref­er­ence fre­quen­cy of the a‑chromatic scale.
1 = 1 Hertz — the ref­er­ence fre­quen­cy of the c‑chromatic scale.
It is one of the 12 scales of Nat­ur­al Tun­ing.
Nat­ur­al Tun­ing con­sists of the pitch ref­er­ence fre­quen­cy and of pure inter­vals, whose fre­quen­cy ratios are the quo­tients of nat­ur­al num­bers.
All is based on the nat­ur­al over­tone series.
Just (pure) into­na­tion is the only nat­ur­al inter­val design.