300b, x45, 211, etc.

The Cary is one of my favourite amps for it's sweet, forgiving sound, my AES version is similar. That said both amps in stock version suffer from a design error that causes slew limiting, an inability of the driver circuit to provide enough current to the output tube to allow the high frequencies and fast transients to react quickly enough. The result is rolled off, slightly sluggish sound. In the AES, the 300b's can be replaced with 2a3's or 45's and the problem is solved. Otherwise the driver stage can be redone ( I wrote it up in Glass Audio magazine in the 90's ) and the result bears very little comparison from the stock circuit- very fast, detailed sound. If you can put 2A3's in your Cary, reducing the bias current %20, you will get a taste of what single-ended is capabile of.
Good Luck and good listening
Richard

Interesting Glassaud, about the AES topologies.

I use a Rocket, and have never had any clipping at 20w in triode. Maybe during a test of the system or something, but not in daily use (at least to notice while listening normally). It's the original one with the 6922 inverters. I have found it to be superior in almost every regard to the design at 30w triode using the 12AX7 inverters. I've heard them next to each other, and found there was really no comparison. I like Cary - reasonable customer service, decent designs with plenty of options for retubing, including EL34's and 6L6's in the Rocket. But I wouldn't want it if it had that sluiggish sound with the 12AX7's. Of course I've have also found that by cranking the gain, and rasing the bias to about 220 from the stock 200 (something Dennis recommends actually) at the input, I can listen to rock just as easily as chamber music. I use a vintage phonostage with adjustable gain and equalization. It's solid state, pretty modified, run through a UL tube preamp, and it makes the gain pretty hot. It can get uncomfortably loud, but doesn't clip. The bass is also very tight run this way.

Of course, 20w is not 2-8w. But I do think the philosophy of "the first watt should be enough, the rest should be back up", is the best way to get a real dimensional life-like sound from a system, regardless of loudness, front ends, speaker pairings, etc.

I just use a pair of Paradigms for my speakers, which while not awesome speakers, are reasonably sensitive and good buys besides. I've heard many salespeople say (anonymously) that they bought them because at the end of the day they did many things right that the $3000-6000 speakers did wrong. My room is an L-shaped (yuck) 40 square feet, and the dispersion of the Paradigms is not laser tight, like it was when I was running them with Marantz mono's at 125w. They sound better, and more holographic at a KT88 20w.

The other great myth of SET's is that spec's are everything. It's one of those few times when you have to actually try it to really know if it works. Hopefully there's always a friend with a system to poach on to try stuff out, or a friendly audio store (or at least one that will put up with bringing in equipment - hopefully they are curious about what they aren't carrying).

Very interesting Biomimetic, the Rocket uses some dc bias in the out put transformers, just as in single ended-the ONLY push-pull design to my knowledge that does so . BTW I've heard the paradigms and couln'd agree more, just on low powered SETs I lean toward Klipsch- say what you like the man had some brilliant ideas that deserve our repect. Dennis used some great ideas, truly innovative in the Rocket- I'm tempted to try one myself. This from a man hooked on SE from the begining.
Good luck and good listening
Richard

Glassaud,

You bring up a good point that can be extended to many 300B amps. In my opinion, many commercial 300B amps use the wrong driver which leads to the problems Glassaud describes. These problems contribute to the general opinion about 300B's that were mentioned in post by Gregm. This is probably due to manufacturers having to use readily available tubes rather than rare and hard to obtain tubes. The 6SN7 driving a 300B is a common design but with common problems. In think the 2A3 and 45 are easier to drive so they don't have this problem.

About Klipsch - once the man, always the man. He and Bob Carver pretty much to my mind are two of the great contrarians of the audiophile world.

I hesistated to bring up the Rocket, but it is a cool design, and with the single-ended-like output (though not 100% there) it was definitely the way for me to get my feet wet and still have a lot of choice. I have toyed with getting rid of it, but never can quite pull the trigger when someone offers me money. I may go so far as to say it's Had's most original design.

Rchau - interesting about the 6SN7 topology and implementation with the 300B. Can you explain - I'm interested. What would the other ways of doing it be?