Just arrived. Sony APM-22ES speakers. Square drivers!

They look just like these on The Vintage Knob, and appear almost new.I will listen for a while (currently with an NAD 3140 integrated amp that arrived today too), and weigh in with my opinion of the Accurate Piston Motion concept. Here is a site dedicated to the APM technology. The japanese translation is funny, but I think I understand the designers intentions. Pictures tomorrow.

Update 2 hours later: The speakers sound great. I have to share the Google translation of the explanation of the APM technology, from the Sony APM home page:

To clear all the conditions of APM speakers speaker audio in the digital age

1 [sound] Komoranai planar: the conventional cone-type speaker, leading to effects of air = cavity resonance structure in the shape of megaphone rolled paper. APM speakers, expelled the disturbance of the frequency characteristic cavity effectively cut off the source of a flat diaphragm. Eliminated the sound booming.

2 [square] there is no distinctive sound: The speaker diaphragm of the APM, light and durable honeycomb sandwich structures are used in the body of an aircraft or bullet train. Yelling diaphragm material sandwiched between two skins of hexagonal honeycomb cores, 500 to 1,000 times the flexural rigidity of the conventional cone-type (comparison), the degree of variation in actual operating conditions is 1 / 20 to 1 / 30 (comparison) contained within a. Thus, the very slight vibration-toxic split. Moreover, adopting a simple rectangular patterns of vibration compared to the split round, effectively canceling vibration split. There is no distinctive sound.

3 sounds fuzzy four-point driving: A rectangular diaphragm, the turning point of oscillation in position dictated split. You preach to drive the point where you can eliminate the vibration of a specific mode split. In fact, the APM Ufua speakers, a point driven four-point milestone is concentrated in low-order mode of vibration division. Greatly expanded the range piston Nick Castle, motion, sound and produce clear and Boyakezu.

4 [sound]濁Ranai DDSD: Ufua of APM speakers, DDSD to directly drive the front and rear skins of the diaphragm and (direct drive dual surface) technology. This Tainamikku濁Rasezu digital sound source and play to clear.