Sony made two speakers for the Esprit line which used APM drivers in the early eighties. One was a large rectangular monolith which was a four way design I think. The second model was a two way design also very large but with rounded sides. They cost $12,000 and $8,000 respectivly. They sounded good especially the two way. Other speakers I had listened to at the time were the Hill Plasmatronics, ESS Transar, and the original 801's. The Hills were $10,000 and most other exceptional speakers at that time were less. This APM is an example of trickle down technology, sounding great in the Esprit but leaving much to be desired in their mid-fi brethern. APM drivers are also hard to repair because of their unusual surrounds and multiple voice coils.
