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To prep for proper fratricide—oh Brutus, where art thou?—I wanted maximal resolution and a copasetic load to move from hairsplitting to successful backstabbing. An easy load meant my 93dB soundkaos Wave 40 tonewood widebanders with auxiliary ribbon tweeters. High resolution wanted the most lucid source and most neutral preamp. Still in from its review, the DAC became Lindemann Audio's musicbook:15 running the latest Asahi Kasei AK 4490 chip driven by 352.8kHz signal upsampled from 16/44.1 in 64-bit software on the iMac. The preamp was my Esoteric C-03 transistor deck set to zero gain to act like a passive, albeit with high voltage rails and fully impedance-compensated buffer.


For Round II and to ratchet up raw transducer resolution whilst simultaneously hobbling the amps with a tougher load, I'd swap in my Aptica ceramic towers augmented by Elac's omnidirectional ribbon super tweeter. Though only 85dB for this transmission-line 2-way, I would have plenty of upfront gain between the DAC's fixed 2.5Vrms output and Esoteric's up to 24dB of selectable gain. I was ready for a rare exercise: roll transistors.


Here valve fans have all the fun. Occasionally socketed opamps allow transistor fans to plug and play a bit too. But when it comes to power JFets, Mosfets, BJTs and their sort, very few of us have any opportunity to evaluate their sonics in otherwise mostly identical circuits. Laissez les bon temps roulez? You bet!


But first, a look at what we're about to roulez, précisément.


Somewhat squarish black three-legged bits, four in total. For sex appeal, glitzing it up between 300B, 2A3, 45 and PX25 triodes or 845/211 transmitters is a far bigger show. For sonics? You might be surprised by what minimalist transistor circuits tweaked by a maestro of Nelson's caliber can offer.

To remind ourselves of the bigger picture which these critters belong into, here's the entirety of the F6: a super complex mega dense circuit that begs the question: if this is all we need to get 50 superb-sounding watts into 4 ohms, why is so much else so much more, er... basic? Knowing what to do without is just as important as knowing what's essential. Which, actually, might be one and the same thing.

Here is the Jensen input transformer of which, obviously, we're getting two, one per channel.

And finally, here's the DIY F6's output device, the subject of our rolling affections.

Except for the writing, it really looks the same as the other guy. Now we're ready to listen.

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