Swiss company. In the 80's of the 20th century "ACR" produced highest quality loudspeaker boxes with magnetostats in the tweeter range. Some boxes also had magnetostatic midrange drivers from Fostex. In addition, the speakers were also offered as kits and reached top positions in comparative tests by Audio and/or Stereoplay. Today the company only sells car hi-fi.
- http://www.isostatic-audio.de [link to a very comprehensive page on the ACR RP Isostatic series]