It seems I spoke too soon. Last week, I profiled the Audio Note Gaku-On monoblock, calling it the most expensive power amp I know of on a per-watt basis, which was a true statement at the time. But as soon as I posted that profile, Cornelia Davis of Audio Federation informed me of another tube-based monoblock that, watt for watt, costs even more—the ML3 Signature from Brooklyn-based Lamm Industries.

Like the Gaku-On, the ML3 Signature is a directly heated single-ended triode (SET) monoblock, operating in pure class A mode to produce 32 watts into 16, 8, or 4Ω, with separate outputs for different loads. Whereas most SET amplifiers work best in the midrange, Lamm claims the ML3 to be one of the only such amps to reproduce the entire audible frequency spectrum with equal aplomb.

This appears to be the ultimate tweaker's power amp. The overall circuit topology uses no overall feedback, but you can introduce two different levels of negative feedback in the output stage if desired. (Stereophile editor John Atkinson preferred the sound with no feedback in the demo he heard.) Also, a multi-turn trim potentiometer lets you adjust the plate current of the GM-70 output tube.

The power supply is completely separated from the audio electronics, preventing any untoward interference. And of course, only the finest components are used throughout both chassis, including custom-made output transformers.

So how much? $139,900/pair for 32Wpc, or $2186/watt, which edges out the Gaku-On at $185,000/pair for 45Wpc, or $2056/watt. As I've said before, if you can consider spending that kind of moolah on power amps, you'd better audition them both with the speakers you intend to use before whipping out the Titanium card. In any event, several respected audiophile journalists have raved about the ML3, so I don't doubt that it sounds amazing.