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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 »

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 »

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