What kind of amplification for Martin Logan SL3 ?

The ML's are not all that inefficient, they are rated 89dB/watt at 1M, which is about average these days. But they DO have a low impedence dip of 1.5 ohms. This drives most amplifiers just wild. Tubes suffer most, as their transformered output is only designed for a level-impedence load, they have taps for 8 ohms, 4 ohms, etc. At other impedences, and into reactive or capacitive loads, (and the ML's certainly qualify for THAT), all tube amplifiers and some solid state amplifiers distort and/or modify their frequency response output. One's impression of "cold" or "warm" is actually caused by the modificacion of the frequency response plus added harmonic distortion, lots of it in the case of tubes, like 5% or 10%, as the amp tries to drive the difficult load that the ML's present. The SOLUTION to this situation is to purchase an amplifier that has large current and voltage capability at low impedences, and that has enough power to drive the ML's to a reasonable level at the same time. To play the ML's at 103dB, one needs 256 watts of amplification (it's a simple mathematical calculation). Then it's a question of selecting an amplifier that provides this power into the ML SL3's 4 ohm nominal impedence AND can drive a 1 ohm load to the approximately 800 watts needed to provide a flat-bandwidth output. There are many good solutions, some for even under $1000. Not to mention brands here, feel free to email for some suggestions.

CELLO 1MEGA...& 350 POWER IS BEST..I.M.O. I USE QUEST-Z WITH MARK38 & KRELL KSA 50 S. IT'S GOOD BUT NOT A BEST. AND IF YOU WANNA GOOD QUALITY OF SOUND,USE TRENSPERANT CABLES... OR MORE WANNA SOUNDSTAGE, MIT CABLE IS GOOD

LEVINSON LEVINSON LEVINSON LEVINSON try it and you will see

I have the Martin Logan Aerius, the smaller version of the SL3's and use a pair of Meridian 557's (400 watts into 4 ohms and high current delivery) which sound wonderful, you need power of this order to make them sound right, plus bi-amping as I have done with one amp for the panels and one for the bass makes a HUGE difference to every aspect of the sound quality.

If you're the type of listener that is obsessed with "breaking-glass" cymbals and "thunderclap" bass, you're gonna need solid state with plenty of watts which cost plenty to do right. If, like me, you prefer to get directly to the heart of the music ...put on an album and enter the world of live, in-room entertainment presented for your exclusive attendance, you've just got to try single-ended triode tubes. Admittedly, the majority of designs are low (less than 10watts) in true Class A / Zero Feedback (The ONLY way!!!). There are however a few designs which take advantage of the larger 211 and 805 power tubes, and can double that power delivery! Don't be discouraged by the maths! These amps will drive loudspeakers that they shouldn't. My 8 watt Cary's drive anything 88db sensitvity upwards. And don't believe that the bass is soft and furry. What's there is timbrally correct and tuneful. But the heart of the message is in the amazingly natural and wholistic sound that can be achieved. With a superb investment like the SL3's, you owe it to yourself to find a good dealer who is not only honest enough to admit that no, he hasn't actually heard it for himself - but will also go to some trouble to set it up for you. The Cary equipment gets my highest praise by the way. Good luck!