After I searched the net, I got this one from Sophia Electric website. This user seemed had issues as well. Maybe you are the lucky one.
------------------------------------------------------
Received date: July 9, 2014
Dear Sue of Sophia Electric:
I am rediscovering my music collection with my new Sophia Electric 91-01 amplifiers.
Rewind a few years back. Based, in part, upon Arthur Salvatore’s recommendation, I purchased a pair of CST Frankensteins II 300B amplifiers. Later on I purchased a pair of CST Pure Reference speakers.
After reading reviews, I tried the Full Music carbon plate 300Bs. One of them died prematurely within a few months. Later on, I tried the KR tubes, again trying to extend the curve. One of them died prematurely within a week. Fortunately, I got my money back. Finally, I ordered the Sophia Electric Royal Princess 300B tubes. For a few days I experienced an enhanced curve I had thought unattainable with a 300B power tube. After a few days (less than a week to my recollection) of listening (I say days as I am retired and actually listen to music most of the day), the same side had a “fireworks” of failure. Again prematurely. I spoke to Sue at Sophia and explained what happened. Without hesitation, she sent a new pair after I explained to her that I would have an audio tech look at it. The technician found nothing wrong with the CST amps. I even called the designer of the CST amps who said “You can use any tube you want”. This was after I related to him what happened. I quickly lost faith in these CST Frankensteins amps. The CST speakers though are still going strong.
Based in part on Jeff Day’s review which I read and re-read, I purchased the Sophia Electric 91-01 300B amplifiers. I got them about a week later. That was about two weeks ago. And now, I am re-discovering my music collection! I hear sounds at the “outside ends” of the listening curve that I never knew were recorded on the medium. Wow! Congratulations Sophia Electric! You have made a believer from me. The down side, of course, is that you can tell very easily when a recording has been badly made.
The 91-01 amps put out about 8 watts per side. Of course, if you are looking for what I call “megawatts” amplifier, do not look here. So you need speakers that are of “easy to drive” if not rated “high efficiency”. Parenthetically, after the CST “killed” three 300B tubes, I used my “spare” amplifier, producing two watts per side, and my speakers had no problem whatsoever. I guess the end result is “if the first watt sucks, why keep going” as the manufacturer of that two watts per channel amplifier said.
You may notice that I do not use technical terms anywhere in what I wrote. The answer is simple. I do not know the meaning of these technical terms. I do not write about something I know nothing about. But I do know about music. When I was working and could afford it, I went to a lot of concerts of “live” music. And to me, that is the only way to learn about music.
If you want to hear all of your music (from a recorded media), you cannot go wrong with Sophia Electric.
Jac
----------------------------------------------------------