The FiiO FT13 is a closed-back over-ear headphone with amaranth wood ear cups, a 60 mm dynamic driver, and a W-shaped diaphragm, and is Hi-Res Audio certified.

The FiiO FT13 is a closed-back over-ear headphone whose ear cups are carved from South American amaranth (Purpleheart) wood. The wood is dried, then aged for ninety days; each cup reveals a unique grain and a colour that develops a patina over time. Dense and hard, this wood limits resonance for a cleaner, faster sound.
The FT13 is fitted with a 60 mm dynamic driver, a size rarely seen in its category. Its W-shaped diaphragm, a composite of wood and wool fibres, increases the effective vibrating area by 25.8%. The result: deep, powerful bass, fast transients and reduced distortion.
Beyond the natural isolation of the wooden cups, the FT13 combines a standing-wave dissipation chamber, absorbent felt and a U-shaped damping tube that reduce ambient noise by up to 26 dB. The same tube lowers the cavity's resonance frequency for deeper, cleaner bass.
With an impedance of 32 ohms and high sensitivity, the FT13 is happy with a smartphone, tablet or computer. Its hybrid cable of Furukawa monocrystalline copper and silver-plated copper ends in interchangeable 3.5 and 4.4 mm plugs; 6.35 mm and XLR-4 adapters are supplied, as are lambskin and suede ear pads. Hi-Res Audio certified.
Data sheet
Specific References
The FiiO BTR17 is a portable Bluetooth DAC and headphone amplifier with dual ES9069Q DAC, a THX AAA 78+ amplifier and a desktop mode delivering up to 650 mW.
The FiiO K11 R2R is a desktop DAC and headphone amplifier featuring a fully differential 24-bit R2R DAC, NOS/OS modes, and 1,300 mW of power.
The FiiO K11 is a desktop headphone DAC and amplifier with a CS43198 chip, balanced 4.4 mm outputs and 1400 mW of power.