The Danish brand Raidho is world-famous for its high-end loudspeakers. In the top-of-the-line TD series, the TD1.2 represents the "smallest" model. Join me in exploring the exciting question of how big and good a compact transducer can really perform when the effort is taken to the extreme.

My expectations are high and curiosity is great. The speakers are quickly set up and placed in the proven position in my listening room. Though they sound quite good, they don't even come close to meeting my high expectations. I should have known it from the start, this has to be burnt-in - the manual refers to about 250 hours. Lets allow the TD1.2 to follow this guideline and in the meantime deal with the technology of this loudspeaker, which is not exactly lightweight. The makers of the TD1.2 have not failed to treat them to exquisite ingredients. And there isn't anything off-the-shelf - all the drivers are, of course, completely proprietary developments and are handcrafted with a great deal of time and effort.

Let's focus on the ribbon tweeter first, one of the hallmarks of all Raidho speakers. In a ribbon driver, the entire diaphragm is electrically conductive and thus also takes over the function of the voice coil. Usually a wafer-thin rectangular folded metal foil is used for this purpose. Due to the short conductor length, the impedance of this type of ribbon is very low (0.2 ohms to max. 1 ohm). Therefore, an additional matching transformer is needed to isolate the amplifier from the extremely low electrical impedance. Hardly any amplifier likes to drive an almost short-circuited load.