THE ESSENCE OF TESLA TECHNOLOGY AK T8iE
Beyerdynamic + Astell&Kern
The first high-end in-ear model with Tesla Technology inside AK T8iE
from beyerdynamic in cooperation with Astell&Kern.

The AK T8iE has been developed and designed from scratch to offer
a superior in-ear sound experience. The finest engineers who developed acoustic reference headphones such as the T1 and AK T5p also designed the AK T8iE, a new landmark in the Tesla family. The dynamic moving-coil transducer offers an extreme wide frequency range with crisp bass, well-balanced mids and crystal-clear highs.

Each AK T8iE is handcrafted in Germany by skilled employees, who have long-term experience assembling small electronic components.
Every single constituent of the AK T8iE is tested and approved multiple times before leaving our assembly line. This guarantees the highest level of quality and long lasting product durability.
About Beyerdynamic
Established 90 years ago, 1924, in Berlin, Germany by Eugen Beyer, Beyerdynamic is the essence of audio technology.

Beyerdynamic is the leading audio equipment worthy of its name that has developed controller-mounted wireless conference system starting with the world’s first dynamic headphone--the DT 48, which is available even today.

As the inheritor of the Eugen Beyer brand, Beyerdynamic maintains the leading corporate image, vision and role put in place by the founder. The technological advancements, continuous innovation and the world’s best quality have made Beyerdynamic the undisputed industry-standard and sound technology market leader.
Tesla Technology inside AK T8iE
The Tesla Technology inside AK T8iE stands for a superb listening experience.
First emerged in 2009 with the reference headphones the T1 and later
the AK T5p, the Tesla in-ear is dramatically miniaturized with the same characteristics of its bigger siblings. An extremely high magnetic flux density within a ring magnet ensures a balanced, undistorted, transparent and neutral sound reproduction.
Sounds like an integrated whole
In comparison to other earphones with Balanced Armature(BA) technology, there is no separate transducer for bass, mid-range or treble tones. This avoids phase problems and the losses of sound quality that results from this. From deep bass to the highest trebles, the AK T8iE sounds like an integrated whole. Additionally, the efficiency of the Tesla transducer is so high that it can easily be matched to a 4-way BA system.
Anatomically shaped for perfect fit
The concha design with the cable running rearwards over the ear has several advantages. The in-ears are easily inserted, and don’t fall out because the cable doesn’t pull. The oval-shaped concha moulds sit very comfortably in the auricle without any pressure. Therefore a variety of ear canals of people from around the world were measured. On top of that five different sizes of anatomically shaped silicone tips and three pairs of Comply™ foam eartips ensure the perfect ear for every ear.
Great flexibility
All cables are Kevlar-reinforced and exceed highest quality demands, steeled for everyday use and mobile application. Besides the standard 1.3m cable with the general-purpose 3.5mm plug there is an additional balanced cable for Astell&Kern devices(works with AK100 Ⅱ / AK120 Ⅱ / AK240 / AK380). It provides a balance output with its specific 2.5 mm 4-pole terminal. A leather case stores the in-ears safely for transport.
Handmade in Germany
Products from beyerdynamic are being developed and mainly hand-manufactured in Heilbronn. Aside from the fact that each AK T8iE is handcrafted in Germany by skilled employees, even the heart of the in-ear the Tesla transducer and the diaphragm are made in our own factory. All parts are tested and approved multiple times before leaving our assembly line. This guarantees the highest level of quality and long lasting product durability.
Internal Structure
Connection cable with male MMCX connector
Eartip
Inner housing
shell
MMCX
female plug
Earwax
protection
Diaphragm
with voicecoil
Outer housing
shell
Diaphragm
suspension
Tesla Magnet
assembly
Specification
  • Transducer type
  • Operating principle
  • Frequency response
  • Impedance
  • Total harmonic distorsion
  • Power handling capacity
  • Nominal sound pressure level
  • Sound coupling to the ear
  • Cables
  • Connector
  • Weight without cable
  • Dynamic, moving-coil
  • closed
  • 8 – 48,000 Hz
  • 16 Ohm
  • <0.2 %
  • 10 mW
  • 109 dB SPL
  • intra-aural
  • two cables: one for balanced-mode use, one for unbalanced-use 1.30 m, two-sided, detachable
  • MMCX at earphones
    / 3.5 mm 3-pole jack plug on unbalanced cable / 2.5 mm 4-pole jack plug on balanced cable
  • 7 g per pair