Dynaudio Esotar2 110, Manual

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Esotec MD 142
5.6μF
6.8Ω
Soft Dome Midrange
Esotec MD 142
Similar to the MD 102 tweeter in principle, the new Esotec MD 142 is a
75mm (3-inch) diameter soft dome midrange design intended for high
performance three- and four-way audio systems.
As typical of all Dynaudio tweeters and soft-dome midrange units, the MD 142
features a large diameter aluminum voice coil with a centered magnet housed
in a relatively compact and shallow enclosure. Suspended in ferrofluid for
controlled damping, an extremely light aluminium voice coil drives the dome.
Aluminium has proven to be an ideal material for Dynaudio’s oversized
voice coils due to its extremely low mass, which in turn allows a larger coil
diameter and more windings as compared to conventional designs. The heat
produced by the voice coil is dissipated to the magnet system with the help
of ferrofluid cooling liquid. The precisely optimized dome geometry and the
low mass of the internal moving parts ensure a very transparent and detailed
reproduction of all frequencies. In most dome driver designs, the surround of
the driver and the outer edge of the driver membrane are moving in opposite
phase and canceling each other’s output at various frequencies. Dynaudio
has undertaken extensive research into the shaping of these parts to ensure
that the long linear excursions essential to high output levels are maintained
without this type of interference.
The Esotec MD 142 is housed in a compact self-contained enclosure with
a vented pole piece and damped rear chamber. It includes an integrated pro-
tective grille, and requires no additional airspace for installation. It thus may
easily be integrated into a wide range of install applications and locations,
including kick-panel, in-dash, in-door or rear deck mount placement. In tan-
dem with the incredibly powerful Neodymium magnet, the sound reproduced
by the MD 142 is smooth, detailed, dynamic and simply amazing.
Thiele Small Parameters
Nominal impedance Znom 8 Ω
DC resistance Re 5.3 Ω
Voice coil inductance Le - mH
Resonance frequency fs 475 Hz
Mechanical Q factor Qms -
Electrical Q factor Qes -
Total Q factor Qts -
Mechanical resistance Rms - kg/s
Moving mass (incl. air load) Mms - g
Suspension compliance Cms - mm/N
Effective dome diameter d - mm
Effective piston area Sd 52 cm²
Equivalent volume Vas - l
Force factor BL - Tm
Recommended frequency range 700–6000 Hz
Magnet and Voice Coil Properties
Voice coil diameter dc 75 mm
Voice coil height hc 5.5 mm
Linear excursion, peak to peak 2.5 mm
Max. excursion, peak to peak 5 mm
Power Handling
Nominal long term IEC 100 W
Transient (10 ms) 1000 W
Mechanical Properties
Net weight 0.75 kg
Overall dimension ø 121 x 66 mm
SPL
Red line: on-axis response
Green line: 30° horizontal
Blue line: 60° horizontal
Measurement conditions:
Level: 2.83 V
Distance: 1 m
Measured in a large baffle
Facts
Coated textile dome
Large 75 mm voice coil ensures
high power handling and low
compression
Internal magnet structure with
vented pole piece
Aluminium voice coil wire results
in a low moving mass
Shallow mounting depth
Integrated protective grille
Ferrofluid adds damping and
increases power handling
Impedance
(with and without impedance
correction circuit)
Red line: impedance, free air
Green line: impedance,
free air with compensation.
Measurement conditions:
Level: 3.16 V, 50 ohm
Driver in free air
Impedance compensation circuit