Optimus Pro LX5 Linaeum Tweeters

From time to time we see interesting new variations on the loudspeaker theme; sometimes manufacturers come up with better cone materials for their mid/bass units, and occasionally interesting tweeters pop up. Recently, there has been a renewed interest in ribbons, but other types have come and gone too. For yours truly, one of the most interesting was the unique Linaeum ‘figure of eight’ dipole design, which the British hi-fi market saw in the rather cool looking Realistic Optimus Pro LX5 in 1995.

Conventional dome tweeters use a coil of wire through which the electrical signal carrying the audio passes, and this is suspended between the circular poles of a ring-shaped magnet. As the current alternates, it moves the dome or cone forward or backward to move the air, thus producing sound. The Linaeum tweeter’s voice coil is flattened vertically and suspended between opposed rectangular permanent magnets placed on either side which push or pull two semi-cylindrical sheets of mylar film, fixed at the other end. These excite the air by rotating back and forth, making sound. Effectively they work as a dipole, radiating both front and back, the result being a very different listening experience to a conventional dome tweeter – as is very clear to hear as soon as you set ears on them!