@Xcalibur255 oh really! They might be 6B4G, which are a close relative but different than 6A5G. The 6B4G is an octal base 6A3. The 6A5G differs from the 6B4G in that it has cathode sleeves, so it is indirectly heated, and the heaters are center-tapped and referenced to ground through the cathode. It is actually a really interesting tube! #1 you don't have to worry about hum or DC on the filaments since it is indirectly heated, and #2 you don't have to center tap your heater winding to cancel hum since it is built into the tube. The creation of the 6A5G was an attempt to reduce the noise of the 6B4G, but create a tube that was interchangeable with circuits built for it. So you get many of the benefits of a DHT without the tricky parts.
I could use 6B4G in this amp, but there will be some AC hum, maybe not a big deal listening on speakers though. Interestingly with the Visseaux 6A5G I have, I am beginning to think the internals are actually more similar to 6B4G. Difficult to see, but they may not have cathode sleeves and there is an audible hum when listening. It really isn't a major bother though and I doubt it could be heard when listening on speakers. I would be happy to have them if they turn up
thank you.
I could use 6B4G in this amp, but there will be some AC hum, maybe not a big deal listening on speakers though. Interestingly with the Visseaux 6A5G I have, I am beginning to think the internals are actually more similar to 6B4G. Difficult to see, but they may not have cathode sleeves and there is an audible hum when listening. It really isn't a major bother though and I doubt it could be heard when listening on speakers. I would be happy to have them if they turn up
thank you.
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