The last version of the SL *before* the 'torriod' option was introduced was an easy load for our amps- even the M-60 did quite well on them. When the torroid option was introduced, along with it came the low impedance in the midrange that Albert refers to. No tube amp made could drive it. Since ESLs and tubes are traditional matches, after a few years I contacted SL and suggested that they rethink the crossover so that the impedance would not be so severe.
Dr. West responded with an improvement, introduced about 4-5 years ago that made the speaker easier to drive. In more recent times the newer diaphragm materials have resulted in greater efficiency and reliability, so these days the speaker has become a reasonable load again- our dealer in Chicago demos them with a set of our MA-1s quite convincingly.
In most rooms it seems that you will need about 200 watts to make things go. The speaker is based on the power paradigm so you will want an amplifier that makes constant power, not voltage, with respect to load (for example 200 watts into 4, 8 or 16 ohms), else the system will not make the bass that the speaker is capable of. IOW you need a tube amplifier. It seems that the best choices for the speaker are the CAT, Wolcott and our own MA-2 (about 75% of our MA-2 production is running on Sound Labs).
Albert did have some tube issues with our amps, but he was using NOS American tubes which were proven unreliable in our amps even way back then (Albert has not had MA-2s for about 10-11 years). Its curious that the American tubes seem so much less reliable than the Russian and Chinese tubes, but they were built to a different spec, and our amps were made for what was in production, part of our 20 Year design rule. Despite that our newer amplifiers are apparently more accommodating of the NOS Americans, but we still recommend the imports.
Dr. West responded with an improvement, introduced about 4-5 years ago that made the speaker easier to drive. In more recent times the newer diaphragm materials have resulted in greater efficiency and reliability, so these days the speaker has become a reasonable load again- our dealer in Chicago demos them with a set of our MA-1s quite convincingly.
In most rooms it seems that you will need about 200 watts to make things go. The speaker is based on the power paradigm so you will want an amplifier that makes constant power, not voltage, with respect to load (for example 200 watts into 4, 8 or 16 ohms), else the system will not make the bass that the speaker is capable of. IOW you need a tube amplifier. It seems that the best choices for the speaker are the CAT, Wolcott and our own MA-2 (about 75% of our MA-2 production is running on Sound Labs).
Albert did have some tube issues with our amps, but he was using NOS American tubes which were proven unreliable in our amps even way back then (Albert has not had MA-2s for about 10-11 years). Its curious that the American tubes seem so much less reliable than the Russian and Chinese tubes, but they were built to a different spec, and our amps were made for what was in production, part of our 20 Year design rule. Despite that our newer amplifiers are apparently more accommodating of the NOS Americans, but we still recommend the imports.