ATC 20T Floorstanding SpeakersBoth Speakers are in Excellent Condition! This speaker system is based on the SCM20 and uses a tall boy enclosure. The basic design and internal volume are the same as those of the SCM20, and the extension part corresponding to the stand is sound tuned as a pure stand. A 18 cm cone type woofer is installed in the low range. This unit has a structure in which a short voice coil of 8 mm width moves in a magnetic circuit in which the gap length is set to