I've been thinking about changing my amp from Sovtek 6B4G tubes to 300B tubes by bringing filament voltage down to 5v and using a tube adapter. The key here is that the Sovtek 6B4G can be pushed much harder than a NOS 6B4G, which was actually a paralleled triode inside the envelope. The Sovtek is a single plate and has been claimed to really be a 300B in an 8 pin base and a higher filament voltage. Maybe the original 300B filament could take the higher voltage anyway without any ill effects. My amp was running with these somewhere higher than a 2A3 operating point and at the low end for a 300B.
So, as I'm looking at 300B tubes I've read that the Genalex tubes are considered a decent tube among the lower priced 300B, all being relative of course since 300B tube prices are astronomical. Then I started looking at the online stores and look at the pictures and it struck me. These tubes are the exact same construction as the Sovtek 6B4G that I already have. They are both made by New Sensor, which I kind of knew, but it hadn't occurred to me that these are really the same tube. One other thing I noted is that these tubes sometimes have OTK markings, which was believed to be a military inspection mark, but when I looked it up using my newly learned Cyrillic skill it just means "inspection station", not necessarily military. It is surprising to me how much I can understand of Russian just because I can read the script now.
So my guess here is that they are branding these to be a higher quality version of their 300B, but is it just branding? Do they select certain tubes to be higher quality, do they build them better, what exactly is it that they do? If all it is is the branding, 6B4G are much cheaper by at least half and I'll stick with them. I'd love to get a quad of the premium types like the EML or PSVane WE copy or Shuguang Treasure, but that isn't happening. $$$$.
Anybody with experience with these tubes care to comment?
So, as I'm looking at 300B tubes I've read that the Genalex tubes are considered a decent tube among the lower priced 300B, all being relative of course since 300B tube prices are astronomical. Then I started looking at the online stores and look at the pictures and it struck me. These tubes are the exact same construction as the Sovtek 6B4G that I already have. They are both made by New Sensor, which I kind of knew, but it hadn't occurred to me that these are really the same tube. One other thing I noted is that these tubes sometimes have OTK markings, which was believed to be a military inspection mark, but when I looked it up using my newly learned Cyrillic skill it just means "inspection station", not necessarily military. It is surprising to me how much I can understand of Russian just because I can read the script now.
So my guess here is that they are branding these to be a higher quality version of their 300B, but is it just branding? Do they select certain tubes to be higher quality, do they build them better, what exactly is it that they do? If all it is is the branding, 6B4G are much cheaper by at least half and I'll stick with them. I'd love to get a quad of the premium types like the EML or PSVane WE copy or Shuguang Treasure, but that isn't happening. $$$$.
Anybody with experience with these tubes care to comment?
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