Currently at this point in time, due to the political situation with the US, we will no longer be shipping into the US
 
Restarting EPOS could only mean re-creating the most famous model, the ES-14. This was a 2-way speaker in a fairly big cabinet and classic looking cabinet, to be used on a dedicated stand. The design should be classic, not lifestyle, only doing things that help with the sound and as straight forward as possible.
 
Analyzing the old construction was interesting. It used a 7“ woofer with Polypropylene cone and an underhang coil with a huge magnet, but multiple layers of VC winding to make the whole coil heavy in order to get a sort of roll-off in the response curve of the woofer. The size of the woofer was not following any standard – too big for a 6.5“, but too small for an 8“. But it was a clever choice, because you could get more drive at lower frequencies more like an 8“ and a midband character closer to the 6.5“. 
 
28mm VC for better performance at the lower end of the tweeter range. The dome itself is made out of an Aluminum alloy with additional ceramic coating to increase the stiffness. Together with the fabric surround and a shaped Mode control ring, the resonance peak of the tweeter is around 30kHz, shifting it out of the 20kHz limit of human hearing. The magnet system uses Ferrite magnets and an improved cavity combination to minimize distortion. Ferrite is the better material for a tweeter if a small size is not needed. It offers a lot more “air“ behind the dome and the surround and avoids compression and harmonic distortion because too small cavities. A copper cap in the magnet reduces distortion and increases level at very high frequencies. The tweeter used no waveguide for sound reasons. To protect the dome, an oval asymmetric mounted perforated metal grill has been added.
 
This part is not removable and was used during the voicing of the speaker. The massive metal plate of the tweeter is only touching the cabinet on 4 points around the screws (idea taken from Roy George of NAIM with his blessing) to reduce a transfer of energy between tweeter and cabinet baffle. The tweeter has its own cavity in the cabinet. 
 
A 7“ driver designed for use in a ported speaker plus compensation for higher resistance air coil. Choice of Polypropylene as cone material was set from the beginning. Polypropylene is a nice material – very consistent, can be made with different filling material like MICA and it can even be injection moulded for funny shapes or variations in thickness. Combined with a low damping rubber surround, it delivers lots of dynamics with very low colouration.
 
The 36mm voice coil of the unit was a relatively straight forward choice. It uses a 18mm long 2-layer winding of copper wire on a non metallic TIL former (TIL is a Glasfiber/Epoxy mix ). The shape of the magnet was optimized, using simulation, to have the best linear BL behavior and a very low variation in inductance over the movement of the coil. This gives you the lowest level of linear distortion and Intermodulation distortion and is clearly different to the magnet system used in the old days. variations. The main magnet is a Ferrite type, the flux compensation magnet reduces the stray field of the magnet and set the right BL for the cabinet size. A Neodymium disk on the pole piece made the BL more linear and a metal phase plug helps to move heat from the coil. All the parts are mounted into a very strong glass filled plastic basket made from scratch. The material was chosen for the combination of stiffness and good damping.
 
Specifications
 
Frequency Response:
40Hz – 23kHz (-6dB) 33Hz – 25kHz (-10dB)
Average Impedance:
> 6 Ohm 
Minimum Impedance:
4.3 Ohm @ 160Hz 
Sensitivity:
87dB @oe2.823V / 1m 
Distortion:
0.2% THD @ 1W 
Crossover Frequency:
2700 Hz 
Bass Unit:
High Power 7“, 35 mm voice coil diameter, Hybrid Ferrite and Neodymium magnet, injection molded cone with variable thickness and Mica filling. Low hysteresis rubber surround. 
HF Unit:
28 mm tweeter with Aluminum/Ceramic compound dome and no Ferrofluid 
Dimensions:
491 x 250 x 385 mm (HWD)
Stand: recommended height 515 mm 
Weight:
16 kg without stand 
Finish:
Walnut, White semi matte, Black semi matte 
Cabinet:
Reflex loaded, damped Sandwich panels, one dimensional braces, Low Noise Port, Duo Frontpanel
Terminal:
German made Low Metal Mass 4 mm Banana terminal