The result of three years of development, the HM9 engine was created entirely in-house, with the accumulated experi- ence that came with MB&F’s 13 years in existence (in 2018) and previous 14 different movements.
Long-time MB&F collectors and fans will recognise the mechanical pedigree of the HM9 engine. Its double-balance with differential is descended from the similar system in Legacy Machine N°2, albeit in vastly different aesthetic form. Whereas LM2 emphasised design purity and the hallucina- tory effect of its suspended oscillators, HM9 is exultant in its celebration of expressive design.
The twin balance wheels of the HM9 engine feed two sets of chronometric data to a central differential for an averaged reading. The balances are individually impulsed and spatially separated to ensure that they beat at their own independent cadences of 2.5Hz (18,000bph) each. This is important to ensure a meaningful average, just as how a statistically robust mathematical average should be derived from discrete points of information.
Two balances beating within the same movement will inevi- tably bring up discussions of resonance, the mechanical phe- nomenon that describes linked oscillators in a state of mutual harmonic excitation. As with the LM2 engine, HM9 deliber- ately avoids inducing the resonance effect. Its purpose in including two balance wheels is to obtain discrete sets of chronometric data that can be translated by a differential to produce one stable averaged reading. This purpose would be defeated by two balances oscillating perfectly in phase, giving the same chronometric data at every point.
HM9 further calls out the MB&F Legacy Machine collection with the curved arms anchoring its balances. The polished appearance finish contrast vividly with the movement bridges.
Limited edition of 33 pieces
Manual-winding in-house movementTwo fully independent balance wheels with planetary differential Frequency: 2.5Hz (18,000bph) Single barrel with 45-hour power reserve 301 components, 52 jewels Hours and minutes on vertical dial display
2 launch editions in titanium grade 5, limited to 33 pieces each, with a NAC movement (“Air” version) or red gold (“Road” version); and limited editions in red gold 5N+ of 18 pieces each, with a NAC movement and rhodium-plated balance wheels (“Air” version) or rhodium-plated movement with red gold balance wheels (“Road” version) Dimensions: 57mm × 47mm × 23mm
Titanium editions: 43 components, red gold editions: 49 components Water resistant to 3ATM (30m); assembled in three segments with patented three-dimensional gasket
Five sapphire crystals treated with anti-reflective coating
STRAP AND BUCKLE
Hand-stitched brown calf-leather strap with custom-designed titanium or red gold 5N+ folding buckle