Favorite 300B: Sophia vs KR

I used a number of 300B amps before and they do work better with certain tube brand. One common thing I found, however, is that the TJ/Sophia brand (mesh and carbon) is not as reliable. It's actual tube life is also 30% - 40% less than advertised, depending on who you buy from.

Initially I thought I was scammed by independent sellers. However, the most recent pair was purchased at full price from authorized dealer. The tubes tested below weak way before they should be.

The tubes don't hold bias well neither. Every other few days, I would need to re-bias the tubes. Since I used different 300B amps, the issue cannot be the amps themselves.

I have not tried the KR300B. Based on my experience with the 842, I would definitely give it a try.

Just my (incomplete) $0.02.

Bsimpson,
Too bad about the shortened life of the TJ/Sophias. I run my amps often and for long periods of use and must say the Shuguang Treasure tubes are just loving it and happily singing along, they have been very reliable so far and sounding grand.

03-04-11: Bsimpson
One common thing I found, however, is that the TJ/Sophia brand (mesh and carbon) is not as reliable. It's actual tube life is also 30% - 40% less than advertised, depending on who you buy from.

Even if yours is a unique experience, it's enough to stop me from dropping $2000 on two pairs of premium Sophia 300B tubes. I'm not willing to take the gamble with tubes that expensive.

I've read only good things regarding the reliability of Shuguang Treasure tubes, so that's what I'd consider first at this point.

Hello Tvad,
I thought you were using the push-pull Wright 2A3 amps.Several other users of the treasure tubes that I know of have had the same stellar reliability as I have.

03-04-11: Charles1dad
Hello Tvad,
I thought you were using the push-pull Wright 2A3 amps.

I do own those. However, for the past year and a half I have been using Audio Note Conquest Silver 300B Parallel SET amps.