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Listening: 4 systems ... with components from Audio Note (UK), Pass Labs / First Watt, and Triode Lab! Part 1.

I've been working on an update about the 4 audio systems that are cooking here at Jeff's Place right now, and I'll be parsing out updates as Parts 1, 2, 3, and 4, as I get a chance to finish writing them up, so stay tuned for much more to come as I get more time... Read More »

Sneak Peek of the Upcoming Positive Feedback Article 'The Art of Vacuum Tubes: Sophia Electric 45 Mesh Plate Triodes and Aqua 274B Rectifier'

As you know, I enjoy providing you with a "sneak peek" of upcoming feature articles for Positive Feedback. In the near future the feature article for Positive Feedback titled The Art of Vacuum Tubes: Sophia Electric 45 Mesh Plate Triodes and Aqua 274B Rectifier will be published, and I thought you might like a head start... Read More »

Jeff checking in: PAF, Sadowsky, Triode Lab, Sophia Electric, Audio Note (UK), and other stuff!

Geez, 2020 sure was a bummer. Coronavirus. 2021 started out rough too, and if you haven't heard yet, the Pacific Audio Fest that all of us have been looking forward to with so much enthusiasm is the latest victim of coronavirus.  I know Lou Hinkley has put a tremendous amount of effort over the last... Read More »

Triode Lab 45 EVO Vacuum Tube Comparisons: Sophia Electric 45 Mesh Plate, Emission Labs 45 Mesh Plate, Sophia Electric Aqua 274B, and Psvane Acme 274B.

I've listened to the Triode Lab 45 EVO single-ended-triode (SET) integrated amplifier in three different audio system contexts now.  First with my Duelund-ized vintage "Stokowski" Altec loudspeakers (HERE) in my main music system (above), where the Triode Lab 45 EVO SET integrated amplifier provided those classic goosebumps musical experiences that the combination of highly-sensitive loudspeakers... Read More »

Richard Wugang tells us about the history of the 45 vacuum tube! Part 1.

Many thanks to Richard Wugang of Sophia Electric for taking time to write about the history of the 45 vacuum tube for us here at Jeff's Place in this Part 1 post. There will be more to come from Richard specifically about the design of his Sophia Electric 45 mesh plate tubes in Part 2. As... Read More »

Jeff checking in ... Triode Lab 45 EVO SET amp, Sophia Electric 45 and 274B vacuum tubes, Pass Labs XP-17 phono stage, First Watt F8 amp, and more!

I've got a lot of really interesting hifi things to tell you about, but it may take me a little longer than usual to fill you in on all the details, as the last few weeks have been difficult on the home front, and it is likely to be that way for a while longer. ... Read More »

Today's Fresh Catch: The Sophia Electric 45 Mesh Plate & Aqua 274B!

Many thanks to Sue and Richard at Sophia Electric for sending Today's Fresh Catch, a pair of the Sophia Electric 45 Mesh Plate power tubes, and a Sophia Electric Aqua 274B rectifier.  The beautiful 2 watt Triode Lab 45 EVO SET integrated amplifier will be the fortunate recipient of these vacuum tubes from Sophia Electric, and I... Read More »

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