Siegfried. It's a most Teutonic name, with Sieg meaning victory and fried not chips sans fish but frieden aka peace. As it turns out, it's a most apt name for a long since discontinued stereo amp by David Berning. I've been told that less than a dozen were ever made. My friend Dan owns one of that not dirty but glorious dozen. You can see it on his top shelf outfitted with Elrog 300B. It's next to the left Thomas Meyer 300B mono with silver/Finemet transformer and mercury-vapour power supplies. With Dan being a well-off and curious hifi lover who's unafraid to commit to custom commissions to sample unusual tubes or topologies, I've had ample opportunity over the years to hear such one-up valve amps or preamps costing up to €40'000 in his evolving system. Thing is, the stubborn Siegfried with its passive attenuator acting as a basic integrated always kept things irritatingly honest. If memory serves, it sold for ~€6'000 when current. Shockingly, that modest investment has kept trumping or at least equalling separates chez Dan's which in combination might have added a solid zero or more to the bill. And the really embarrassing thing—for the competition that is—is that one can easily lift up the Berning with one hand. Using no traditional output transformers nor a power trafo but a switch-mode power supply, it waves off all the manly obsession with 'heavy iron' as redundant and so caveman.

In short, Dan's Siegfried is the only type valve amp I'd aspire to after having sworn off the conventional types. Of course 8wpc are insufficient for my type speaker where Siegfried would turn into Verlustkrieg. Plus, the trouble was that for all his engineering genius, David Berning didn't prove equally gifted as a manufacturer or perhaps even business man. His original stuff had basically become unobtainium. Later, a dealer/distributor in Southern Cali got involved. This led to the launch of the 60-watt $73'500/pr 845/211 Berning monos based on the same ZOTL tech as in the Siegfried; and altogether different price points. Ouch! Then RMAF 2015 in Denver concluded. As a non-attendee, I sifted through various forum posts and magazine show mentions just as our readers would. I wanted to see whether any new introductions I wasn't already privy to would tickle my lust buttons. And there it was: an announcement for a $5'800 ZOTL 40 based on common EL34 to make 40 watts per side, marketed by Linear Tube Audio, licensed from and collaborated with by none other than David Berning. Shazam. Now that is a valve amp I could want real bad.

MicroZOTL headphone amp/preamp

Why? Berning's patented ZOTL circuit upshifts the audio signal onto a 250kHz carrier wave where a tiny RF transformer with a ludicrous turns ratio handles impedance transformation. This allows impedance conversion wildly beyond traditional transformers which must operate in the audio band. Hence the OTL part of the name. It is short for output transformer less. Unlike Atma-Sphere and related conventional OTLs however, there is no need for endless paralleling of very hard-driven tubes to match the output impedance to what loudspeakers require. With ZOTL, it's the minuscule RF transformer which weighs nothing but might contain an extreme non-lossy 1:165 turns ratio. Unusual switch-mode power supplies different from what's in typical class D amps complete the lightweight mechanical picture. Thermally it's lightweight too and far from the space heaters which conventional OTL are. Sonically meanwhile, tubes one might be very well familiar with for signature sonics—take the 300B in the Siegfried for example—sound very different zotl'd; as though steam-cleaned, purified and accelerated beyond all the ills of conventional transformer loading; ills which register fully only by contrast. Given my familiarity with Dan's Siegfried and how fast, lucid and wide-band normal 300B sound in it, I'm feeling alarmingly confident that the 40wpc class AB push/pull ZOTL 40 from Linear Tube Audio should become a real stand-out destination in the contemporary valve audio arts; and a valve amp which transistor lovers like myself could embrace and fancy. If I can arrange for a review loaner, I might have still more to say about it. Here's another web link on it; and one more of Dick Olsher's Denver sighting.