Elrog 300B vs Takatsuki 300B tubes

I have been an audiogon user for more than 10 years. I read audiogon forums often, but I never posted anything. Today I will make my first post.

Elrog 300B failure could be one of the two scenarios or both:

1. Elrog 300B has problem itself.
2. Some of Frankensteins 300B amplifiers if not all have design issues -- huge current surge when the power is turning on. As a result, tubes failed prematurely.

I used to own a pair of CST Frankensteins II 300B amplifiers. The stock tube failed within a month. Within a year, I had encountered 4 300B tube failures. I emailed the designer when I had my 2nd 300B failured. I was assured that the amplifier has no problem, I can use any 300B tubes for the amps, but the problem is I continued to encounter 300B tube failure. After a few month of search, I found a very reputable repairman in California. After he inspected the amps, he told me there was a design issue: huge current surge when the power is turning on. As a result, 300B tubes failed prematurely.

Hi Wjt2005, I wonder if this problem was unique to your particular Frankenstein? I've owned mine for over 6 years and haven't experienced this issue(except for the original Elrogs). I can't speak for other Frankenstein MK II owners but I haven't seen feedback suggesting it's a common problem. It's certainly possible other Franks owners may share your same problem.

I don't think so. I remember someone made similar complaint last year when we had an audiophile gathering.

Well the fact that I haven't had the same tube failures with the same amplifier would suggest it isn't every Frankenstein amp. All I'm saying is how widespread might this issue be? 10,35 or 80% of all Franks? I don't know.

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.

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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

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