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Happy Holidays! Triode Lab 45 EVO tube rolling, 2023 Writers' Choice Awards, and other stuff!

Greetings friends, and Happy Holidays to you! I hope you are all doing great this Holiday Season. 🙂 Here in the Pacific Northwest of the USA we've been inundated with rain from the atmospheric river that is dumping on us, with record levels of rain - estimated at 10 trillion gallons over the last week... Read More »

Positive Feedback Review Sneak Peek: Sexy Blue Tubes - The New Sophia Electric Aqua II 274B Rectifier!

The feature review of the new Sophia Electric Aqua II 274B rectifier is now live at Positive Feedback HERE. Enjoy!  As is my custom, I like to give the readers of Jeff's Place a preview of upcoming articles for Positive Feedback, which in this case is the new Sophia Electric Aqua II 274B rectifier.  The... Read More »

Jeff checking in ... Duelund DCA10GA, Belden 8402 ICs, Sophia Electric 274B, Audio Note (UK), 78 record transfers, and other stuff!

Greetings friends, I hope you are doing great! I'll start with the "other stuff" first, which is about my likely last multi-day motorbike ride of 2023 as the inclement Fall weather arrives - which officially signals the start of the indoor audio season!  For those interested in audio only you can scroll down the page... Read More »

Richard gives us a tour of his new Sophia Electric 'Aqua II' 274B rectifier! Now with a postscript of listening observations.

As soon as I put Richard's new Aqua II 274B rectifier in the Triode Lab EVO 45 SET amp I knew something special was going on. Fresh out the box the Aqua II 274B sounded gorgeous: beautifully natural tone, a huge sense of recorded acoustic, gorgeous tone color, a vivid sense of imaging presence, and... Read More »

Today's Fresh Catch: The Sophia Electric 'Aqua II' 274B - hooray!

A lot of us tubeaholics have been sweating bullets about the unavailability of vacuum tubes coming out of China and Russia due to covid pandemic induced factory shutdowns, supply chain issues, and trade restrictions (Russia).  We've all been hoping that everything would get sorted out and vacuum tubes would start to flow again before the... Read More »

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 »

Jeff checking in: Sophia Electric, Pass Labs, First Watt, Audio Note (UK), and more!

It is one of those time periods where I am in the midst of shuffling equipment around between systems in  preparation for upcoming reviews. As you are no doubt aware, the performance of a component is greatly dependent upon the associated equipment in a given system, and the room it is installed in. I've found... Read More »

Sneak Peek: Sexy Blue Tubes, Part 2, The Sophia Electric EL34-ST and KT88-ST Vacuum Tubes!

As is my custom, I wanted to share a "sneak peek" into my next feature review for Positive Feedback "Sexy Blue Tubes, Part 2: The Sophia Electric EL34-ST and KT88-ST Vacuum Tubes!" I'm hoping to have the feature article finished up over the next week, so check back for more in about a week. Enjoy... Read More »

Leben CS600 & CS600X: Tube Rolling with Sophia Electric vs. Electro-Harmonix EL34!

Besides their superb musical & sonic qualities, one of the great sources of joy for owners of vacuum tube amplifiers like the Leben CS600 / CS600X integrated amplifiers are adventures in trying different vacuum tubes to voice their amplifiers to best match their overall system characteristics, room, and their personal preferences.  I've been a huge... Read More »

First Listen: The Sophia Electric Blue Glass KT88-ST in the Leben CS600X Integrated Amplifier! Updated.

Last night I installed the fresh out of the box Sophia Electric blue-glass KT88-ST long-life vacuum tubes into the new Leben CS600X, that's currently powering my vintage Altec A5 Voice of the Theatre loudspeakers in my audio-visual system.  I'm running the Sophia Electric KT88-STs with cathode resistor and plate voltage settings used for 6L6GCs, which... Read More »

Today's Fresh Catch: The Sophia Electric Blue Glass KT88-ST Long Life Vacuum Tubes!

In my "Sexy Blue Tubes: The Sophia Electric EL34-ST and Aqua 274B Vacuum Tubes!" feature review article for Positive Feedback (HERE), I provided a brief history of the EL34 and 274B vacuum tube designs, and then described the various technical performance enhancements that Richard and Sue of Sophia Electric implemented in their flagship Sophia Electric EL34-ST... Read More »

Tube rolling in the new Leben CS-600X integrated amplifier - Sophia Electric vacuum tubes & NOS 12BH7A's! Update!

One of the favorite pastimes of many original Leben CS-600 integrated amplifier owners has been trying different combinations of vacuum tubes in their CS-600 to tailor its sound to what best matches their personal taste. The Leben CS-600 tube complement is four twin-triode 6CS7 vacuum tubes used in the first-stage of amplification, a single slow... Read More »

Today's Fresh Catch: Sophia Electric 12AU7 and EL34-ST!

Today's Fresh Catch is the Sophia Electric 12AU7 and EL34-ST vacuum tubes! I had mentioned to Sue at Sophia Electric about my long term update of the Sophia Electric EL34-ST vacuum tubes in my Leben CS600 integrated amplifier (HERE), and that I would be reviewing the new Leben CS600X.  Sue suggested I give the Leben... Read More »

A look inside the new Leben CS600X integrated amplifier!

The new Leben CS600X vacuum tube integrated amplifier that is in for review has been getting run-in time in my vintage Altec A5 Voice of the Theatre loudspeakers based audio-visual system in the place normally occupied by my gracefully aging original Leben CS600. I was impressed with what I was hearing from the new Leben... Read More »

Quick Comparison: NOS SED "Winged C" EL34 Vs. Sophia Electric EL34-ST Vacuum Tubes

I've been running the Sophia Electric EL34-ST vacuum tubes in my Leben CS-600 integrated amplifier ever since I reviewed them for Positive Feedback back in August of 2017, and I've put a ton of hours on them since then. In my "Summary and Conclusions" for them, I said: "I'm noticing a pattern here with both the Sophia... Read More »

The 14th Annual Positive Feedback Writers' Choice Awards for 2017!

The 14th Annual Positive Feedback Writers' Choice Awards for 2017 are now live here. Actually the Writers' Choice Awards went live a few days ago but this is my first chance to tell you about it. Here's a preview of my little contribution for 2017. You can read the fully story at the link. ¸¸.•*¨*•♫♪... Read More »

A look back at my year in reviewing, and choosing the Positive Feedback 2017 Writers Choice Award winners!

The Editors of Positive Feedback, Mr. Dave Clark and Dr. David Robinson, just sent out a message calling for the writers to turn in their three Writers Choice Awards for 2017. Every year Dave and David's message results in my going back and reflecting on my year in audio, the products I've written about for Positive Feedback, and... Read More »

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