Altiat Cal.1H Electrodynamic Driver Open Back Headphone

The Cal.1H (pronounced "Caliber 1H") is not trying to break new grounds. It's an honest take on Electrodynamic transmission. The Cal.1H employs a 50mm driver with an infilled PET diaphragm. There is enough excursion to produce low-frequencies with ease and linearity without the unnecessary/overbearing side-effects.
The high-sensitivity of the drivers used in the CAL.1H is an advantage for ones who are wanting to correct the Frequency Response to their liking/compensations.

The build of the CAL.1H is primarily unibody Aluminium. The Headband is a mixture of Aluminium and Spring Steel with Delrin buffers which ensure clean action against the surfaces to avoid metal on metal fatigue.
Almost all parts of the CAL.1H are precision machined on CNC Turning and CNC Milling machines.

Technical Aspects:

Coupling : Circumaural
Transducer : Electrodynamic (50mm, Infilled Polymer)
Impedance : ~28 Ohms
Sensitivity : ~105.36dB SPL/mW @1 kHz (approx avg ~104dB SPL/mW @1 kHz)
Driver Matching : Min ~0.1dB to Max ~0.4dB avg throughout the Frequency Response range.

Finish Details:

Gunmetal Grey - The Aluminium housings are Powder-Coated.
Aluminum Silver - Raw Aluminium housings are dry sandblasted.
Solid Ash - Machined from a solid block of Ash wood, while maintaining all the 3D contours of the CAL.1H.