Not everyone needs a power amplifier that can deliver 888W RMS into 8 ohms or 1776W into 4 ohms. You could say that no one needs one of these—or two, if you want to listen in stereo. Most household AC systems can't even provide enough current to deliver all that power. But Simaudio does build Moon 888 monoblocks, and people do buy them, whether or not they need an amp that weighs about 250 lb each and costs $118,888/pair.

The Emitter II Exclusive integrated amplifier, from German manufacturer ASR Audio (footnote 1), challenged my idea of what I could expect from a solid-state amplifier and my thoughts of what might be the best amp for driving a pair of Quad ESL loudspeakers—revelations that were more or less inseparable. After hearing my friend and former neighbor Neal Newman drive his own ESLs with a ca 1975 sample of the Quad 303—a solid-state amplifier rated at 45Wpc into 8 ohms—and after my experiences, in 2016, driving my ESLs with a borrowed sample of the 18Wpc, solid-state Naim Nait 2, I began to think that Quad-friendly transistor amps are easier to find than their tubed counterparts.

It was almost seven years ago that Nelson Pass, whose talks and exhibits I'd covered at many a Bay Area Burning Amp DIY event and audio show, surprised me with a loan of two Pass Laboratories' XA 160.5 class-A monoblock amplifiers. Ten months later, after I'd commented that my system had challenged the XA 160.5s in the bass department, he sent me a pair of XA200.5 monos. I connected those bigger babies to Wilson Audio Sophia 3 loudspeakers and some now-discontinued digital components with Nordost Odin 1 interconnects and speaker cables. Then came my way, toward the end of 2016, the XA200.8 monoblocks ($42,000/pair).