MartinLogan CLS loudspeaker Jack English, CLS IIA, December 1991
The CLS IIA is the most fascinating product in the MartinLogan lineup and, strangely, the most often overlooked. This fact is particularly intriguing given the CLS's stunning aesthetic appeal. Introduced in 1985 to widespread fanfare within the audiophile community, the original CLS was rightly praised for its literal and sonic transparency. It received rave reviews and became the most sought-after speaker for many an audiophile. Oddly, it has subsequently suffered from its early blockbuster success.
MartinLogan used the CLS technology to develop the Sequel, now in version II form. In addition to a curved, transparent electrostatic panel like the CLS's, the Sequel included a dynamic woofer and cost a grand less! The market responded enthusiastically, to say the least. M-L president Gayle Sanders responded with a revision to the even more potent Monolith, now in version III form, which also included dynamic woofers to fill out the much-needed bottom. The audiophile with some financial constraints had the Sequel, and those with greater financial resources had the Monolith. For those with no financial constraints, M-L offered the megabuck Statement. In 1991, still another MartinLogan speaker hit the market: the Quest, with the now familiar hybrid design of an electrostatic top and dynamic bottom, and priced to go head to head with the CLS. But where did this leave the CLS?
CLS I vs CLS II
Before moving on to the performance of the CLS IIA, it is appropriate to review the "report card" of the earlier CLSes. My impressions of the original CLS were mixed. The CLS I had early problems with reliability, something clearly a thing of the past, in my opinion. It did some remarkable things which were detailed in excellent reviews by John Atkinson (Vol.9 No.7), Martin Colloms (Vol.10 No.1), and John Nork in issue 45 of The Abso!ute Sound.
The CLS Is were often criticized for having a glare in the upper midrange/lower treble region that became most apparent during loud passages. There were also its difficult load characteristic, inadequate deep bass, some criticisms of a one-note bass character, limitations in both dynamics and ultimate loudness, phasey/beamy trebles, and an overall lightweight character. On the plus side of the ledger, the CLS Is were: visually stunning; state-of-the-art in overall neutrality and transparency, setting new standards in the resolution of inner detail while simultaneously eliminating much of the sonic grundge we had all grown so accustomed to hearing; devoid of box colorations (they had no boxes); incredibly fast; seamlessly coherent; had good dispersion; were reasonably efficient; and had a marvelous midrange immediacy.
In spite of this dazzling array of strengths, the CLS I really did suffer from significant limitations in deep-bass extension, midbass punch, and dynamics, as well as suffering from some upper-midrange glare. While I admired the CLS I, I did not think it would have wide acceptance due to these sonic limitations. In fact, Nork concluded that the original CLS speakers were destined to become rather controversial. They did.
MartinLogan claimed three significant improvements for the CLS II revision, which was released in January 1989: better bass extension and definition, better high-frequency extension and naturalness, and improved efficiency and power-handling capability. John Nork, Arthur Pfeffer, and John Cooledge discussed the relative strengths and weaknesses of the MartinLogan CLS I and II in issue 68 of TAS. Specifically, they talked about the limitations of the I and such later improvements as better bass extension and articulation, minimization of glare, and, although it isn't mentioned, significantly improved reliability. However, they felt the II was harder to drive and suffered from a loss of immediacy.
These comparisons were relevant for CLS I owners but moot for everyone else. In essence, the Is and IIs were different speakers. If you absolutely loved the original CLS, you may have felt too much had been sacrificed in taming the beast. I didn't love the Is, and felt the IIs were a significant improvement, making the speaker more appealing to a wider number of audiophiles.
The fundamental issue is sonic performance, and here the CLS IIs shone brightly. Bass performance was dramatically improved, as claimed by MartinLogan. The IIs had improved definition, better extension, and a reduction of the one-note character endemic to the Is. Soundstaging and imaging remained outstanding. Dispersion was good for a panel speaker, but was improved by raising the speaker off the floor. Treble extension had also been improved as claimed. The upper-midrange glare of the earlier model had been admirably tempered although not entirely eliminated. Speed, coherency, and resolution of detail continued to define the state of the art. On the whole, the MartinLogan CLS II was a truly great if still perplexing speaker.