The post from @pindac above is spot on. Most people think a 300b is a fuzzy rolled off tube. That is because they heard it in a single ended amp with a mediocre power supply, and most likely an inadequate driver section, and possibly mediocre output transformers. Such as all the entry level Chinese 300b amps. They still are pleasant to listen to, but if you use a really good driver section that never clips before the 300b tubes do and is capable of driving the capacitive load of the 300b, a really killer power supply, actually multiple ones, and really good transformers, the 300b will walk all over any of the normal output tubes such as kt88, el34, etc.... That is what @whitestix heard.... A PP 300b amp done right is very special. I really had no idea how good they were until I spent a year working on one. See some of you in Seattle.
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@donsachs I made this point on another thread just a day or two ago. People get so hung up on the tube, whether a plus or minus, while the circuit design, which is far more important, gets ignored.
Absolutely. I read a great quote somewhere about a million years ago, that a great tube amp was the sum of three things. How good is the circuit? How good is the power supply? How good are the transformers? If you take care of all three of those things you get a great amp with most any tubes. Most commercial designs that are built to low price points make serious compromises in one or more of those areas. If you take care of business, you generally get a great amp.
Thanks for highlighting the dependence of power tubes on driver tubes as well as on power supplies and transformers. My Wavac EC300B depending on whether I use EAT300bs with their preferred Tungsols 6L6 Coke bottles or Takatsukis with their preferred Svetlana Winged ‘C’s have quite different characteristics (bold and powerful vs. subtle and detailed). When you change the driver tubes in either case a significant bit of the magic is lost. At the top end SETs are simply unbeatable in terms of musicality and soundstaging.
@antigrunge2 Glad you have an amp you love. What I meant above is the design of the driver section of the circuit. Your amp is using a 6L6 to drive a 300b, which is a good choice. I was referring to many 300b amps that are pushing tubes like a 6SN7 to the max and barely driving a 300b. The first rule of amp design is your driver section should never strain or clip before your output section does. As for the SET vs PP on musicality and soundstaging, well I would submit you've never heard a push pull 300b amp designed like the one Lynn and I have been working on. You might be surprised...
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