©2017 by Dr. Dual

A pair of European 220Volt Martin Logan CLS 1'B' Full-Range Electrostatic Loudspeakers in pristine condition. Many consider the original CLS the best and most useful speaker Martin Logan ever made. It presents a much easier load to drive than the later II version and is cleaner in the midrange and treble. I have used both the NAD 3020 and the Mission Cyrus One to drive them without any problem. Some have commented about reliability problems with the use of the single full width curved panels, so shortly before going on to the CLS II, they updated the original with triple pane panels similar to the II’s (please see the picture). As you can see, the vertical strips break up the extreme curve to which the original production I’s were prone. Call them CLS 1'B' if you wish (Gayle Sanders constantly fiddled with his design and didn’t always say so in the advertising). I have found one confirmation where these were labeled as “1B” (see schematisch pictures taken from internet), though the actual original CLS “1" was simply called “CLS” or Controlled Line Source.

The set is matched, serial numbers 3426 and 3427. As a customer Etienne V. from France pointed out to me, only after electronics series 4XXX or CEAxxnnnn, the speakers are considered real CLS 1B, before that CLS 1. However, the panel serial numbers are CS1CB512 and CS1CB513.
They are in overall very good shape and sound terrific. There is no buzzing or other noise. The light oak side and top rails are extremely clean, as are the stator grilles. Pick up only!

Martin Logan CLS 1'B'