We can inject magnetic oil into the air gap, on request.
We do not recommend it as it gives a small contribution to distortion, caused by the fact that the interaction between different inner damped chambers is brought out of balance as the oil acts as a wall between those chambers, and this can be heard as a very small extra distortion unless we compensate with different changes that will compromise on other parameters.
On the other hand the positive achievements by using oil, such as cooling the voice coil, and damping of minor ringing in the voice coil, might be of importance to some customers, and therefore we can offer to apply magnetic oil to the air gap.
Individual curve sheets:
As mentioned above we can supply individual curve sheets with every single unit, if so desired, especially when matched pairs are called for. Again please observe, that the OW series are born with these curves and therefore no extra charge is taken.
Dome diaphragm coated with "Gold":
We have developed a special "golden-look-alike" coating, which gives the dome a brass-gold shining surface. At the same time, this coating results in a very beautiful sound. All good characteristics as for the D2094-9008-03 is maintained, except for minus Ż dB overall. But the sound is soft and very musical, and tends to be comparable to the D2094-8708-03. The type no. is D2094-8908-G3.
The types OW3 and OW4 are such special colored dome tweeters sold as matched pairs.
Foam ring downloaded flush with front:
We can supply the units with a foam ring downloaded in the surface, for special design and to some degree for absorbing traveling waves along the surface.
Logo on the unit:
Also logo or symbol can be incorporated, but to do so additional tools are needed, and therefore is only affordable with big order quantities.