Recommended Tube Amp for ML CLS I model

CLS's plus REL are a wonderful combination! I'm on the CLS IIz's, not the original, but my understanding is that the sound is largely the same (when turning off the IIz's high-frequency softening switch as I do).

I went through a number of amps, including the Rogue Zeus, ARCs, VTA, VAC, and Hovland before choosing the Conrad Johnson Premier 12 monoblocks. The Zeus and ARC were way too dry for my taste, the VT slightly too dry. VAC and Hovland were competitive sound-wise. The Hovland was the only solid state piece to make it into final round with me, and I really wanted to avoid the hassle of tubes, but it kept blowing a fuse trying to drive the CLSs.

Hi there, I used to import Martin Logans into NZ many yrs ago along with Conrad Johnson, Quicksilver, Counterpoint etc. They sre actually dificult to drive, although it is very humid here which didn't help. Best sound was with the Quicksilver 8417 monos by far. VTL's couldn't drive them. Big Rowlands are an excellent match either 7's or 5's. We had custom built stands to lift them 12" off the floor and angle slightly forward/down, this really opened them up and improved the bottom end considerably.

Dover - are you referring to the Original CLS, II, IIa, or IIz? I know the IIa was a bear to drive, due to it's very low impedance. The original CLS actually had a very high impedance above 1000 Hz, I believe. This made it ideal for tube amps. The series II versions definitely favored SS amps.

HI,
I have the CLS IIA's. I don't think they are any easier or harder to drive than your original CLS's. They both need power and stability. I drive mine with an ARC D250 Mk2 Servo (250W/channel) tube power amp and the sound is magnificent. Originally, I drove them with a Levinson No. 23 power amp. It worked well but not as good as the D250. I also have biamped Kinergetics dual SW800 subwoofers. This is a wonderful combination.

A couple of hints. Do not expect deep bass from the CLS. They just won't do it. Good subs are the answer which will also improve the CLS's dynamic range. Next, the CLS are the most demanding speakers I have ever experienced of the up stream electronics. They are absolutely surgical in their ability to demonstrate flaws in the system. They require first rate preamps, power amps, cables, and everything else. These speakers will not tolerate short cuts. This quality is not a drawback. It's way all speakers should behave but most don't.

For these reasons I do not recommend CLS's as beginner speakers. It takes considerable experience, knowledge and financial commitment to get them to perform to their potential. Sure, you can just hook up your amp and the speakers will speak. But that is just the beginning.

People get drawn into the CLS's because they sound great at a relatively low price. But that is deceiving. To be really successful with them, you will need to buy expensive electronics. If you get it right, they are some of the finest speakers ever made. But you do have to get it right.

Sparky

Sparky,

I have a tonne of experience with the IIz model and was able to make it sing with everything from Gryphon to Innersound to battery-powered Rowlands.

For CLS I, though, it is clear that modestly powered tube amps should be ideal; unlike the II series.

But, yes, I agree that experience is important with any planar speaker.